Growing
What Research Studies Tell Us Are The Best Plants To Repel Unwanted Insects
IN THIS GUIDE Insect Repellent Studies 1) Lemon Balm 2) Lemongrass 3) Lavender 4) Rosemary 5) Bee Balm 6) Bay Leaves 7) Garlic 8) Mugwort 9) Alliums 10) Marigolds 11) Nasturtiums 12) Lemon Scented Eucalyptus 13) Catmint 14) Peppermint 15) Petunia 16) Geranium 17) Pitcher Plant Good riddance, we hope References As gardeners, our relationship with insects can be complicated. On the one hand, bees and butterflies are a beautiful and life-giving presence in our green oases. On the other hand, though, are slugs, snails, mosquitoes, aphids, and various other pests waiting enthusiastically on the sidelines, ready to wreak havoc at a moment’s notice. If you’re at your wits end with slimy critters munching on your plants, aphids sucking the sap from your leaves, and mozzies sucking the sap from you every time you dare try to relax in your garden, then this guide is for you. Insect Repellent Studies There have actually been a number of notable studies into which plants are most effective at deterring insects. These include: Malaria Journal1 American Botanical Council2 Across these studies there is some consensus as to the plants that are most effective at repelling pesky insects such as mosquitos and flies – and we’ve rounded these up below. (If you want to attract more bees, butterflies, and other pollinators, check out our post on the best plants to attract bees). 1) Lemon Balm This bushy herb smells like – you guessed it – lemon. And as you may know, citrus smell – more specifically the chemical compound citronellal – is a deterrent for mosquitoes (that’s why lots of gardening shops sell citronella candles!).3 2) Lemongrass Here’s another plant high in citronellal, which mosquitoes simply will not abide. Also being near lemongrass should protect you somewhat from the mosquitoes’ probing proboscis. See this guide for more plants that mosquitos specifically dislike! 3) Lavender This popular purple plant has the combined benefits of deterring mosquitoes while attracting bees. On top of that, it’s attractive to look at and wonderful to smell – whenever I pass my lavender plants I rub a couple of sprigs and dab the scent onto my forehead for a little burst of relaxation. 4) Rosemary This familiar herb has supposed repellent properties, whether you’re sitting in close proximity or rubbing the oil onto your skin. With the latter, it may be a little strange dabbing a scent onto your skin that’s more readily associated with a leg of lamb, but worry not. The absence of mosquitoes is a worthy swap. If you grow rosemary as part of a herb garden, you’ll be interested to know that other herbs like mint, oregano, and basil also have reported anti-mosquito effects. So if you’d rather smell like a mojito, a plate of pasta, or some really nice pesto, you’re in luck. 5) Bee Balm These distinctive, neon-pink flowers are another plant renowned for their ability to drive away pests, while inviting in desirable garden visitors like bees (hence the name) and butterflies. Bee balm also goes by the name of bergamot, and if you’ve ever used that really fancy hand soap they sometimes have in posh restaurants, you’ll know just how good it can smell. This means that growing the plant for its own merit is an inviting prospect, and the resulting absence of mosquitoes can be considered an added bonus. 6) Bay Leaves Do you like curry? If so, you’ve probably had the unpleasant experience of biting into a bay leaf that’s not been removed before serving. The flavour is great when worked through a sauce, but not so great when you bite down onto the papery texture bursting with full pungency. This pungency, though, is the exact property that’s of interest in discouraging flies from spending any more time with you. Simply scatter a handful of leaves (fresh or dried!) onto a nearby surface and, fingers crossed, you should be left in peace. 7) Garlic Handy in the kitchen and a worthwhile deterrent – this easy-to-grow plant is well worth growing for its plethora of applications. Use it as a companion plant to protect any garden growth that is attracting unwanted insect attention! 8) Mugwort While this plant may sound like something straight out of a witch’s pantry, its scent is a renowned repellent for moths, mosquitoes, and various other flying critters. It’s thought to be so effective, in fact, that some cultures gather dried sections of mugwort and burn them in clumps. The resulting smoke is apparently quite good at getting rid of any nearby insects. 9) Alliums Sometimes you can grow two plants near each other, one of which is famously attractive to humans and the other of which has a natural ability to repel common pests of the first. Alliums and roses are a fine example of such a partnership: grow some alliums near to your prize roses, and their natural scent (which humans can’t detect) will deter aphids, one of the most persistent threats to a healthy rose crop. 10) Marigolds These gorgeous yellow-orange flowers are a common choice for gardeners, and are also naturally repellent to aphids, mosquitoes, and various other bugs. Our favourite plants are those that are a pleasure to behold while also performing some useful function in the garden, and marigolds definitely tick both boxes. 11) Nasturtiums Another plant that falls neatly into the combined bucket of being attractive and useful is the humble nasturtium. A treat to behold, and a guaranteed conversation starter thanks to their peppery taste and suitability for human consumption, these flowers also possess the natural ability to drive away pests – triple whammy! Nasturtiums are able to deter flies, whiteflies, beetles, and many others. They can also be used as a sacrificial plant to lure aphids away from crops. They’re a great choice for protecting nearby plants from unwanted visitations and will make a fine addition to your garden. 12) Lemon Scented Eucalyptus 13) Catmint “Catmint is loved by cats and hated by mosquitoes,” shares Master Horticulturist Peter Lickorish. “The two things may be connected, as scientists have shown that cats are drawn into the euphoria created by the fragrance of the very nepetalactol that helps defend them from mosquito bites.”4 14) Peppermint 15) Petunia 16) Geranium 17) Pitcher Plant “The pitcher plant feeds off flies as its roots cannot access the nutrients it needs in waterlogged soils,” says Peter. “There’s always more to plants’ relationships with insects than we first think.” Good riddance, we hope There you go: eighteen plants that should reduce the number of bugs bothering you and your gardening endeavours, and that have the added benefit of being attractive and useful additions to your garden. Whether you go for the herbs whose aromatic properties will be a boon to your culinary exploits, or the pretty flowers like marigolds and alliums that will make a stunning contribution to flowerbeds and plant displays, you’ve got plenty of options to work with. And remember to check out the Plants for Pollinators scheme if you want to attract more of the bees, butterflies, and other pollinators that make a positive contribution to your garden.5 You can also read about the benefits of wildflower corridors in protecting vulnerable insect populations from harm or even extinction: a great way to remind yourself that not all insects are bad, and that some actively need our help to thrive!6 References 1. Maia, M. F., & Moore, S. J. (2011). Plant-based insect repellents: a review of their efficacy, development and testing. Malaria Journal, 10(S1). https://doi.org/10.1186/1475-2875-10-s1-s11 2. Smith, T. (n.d.). Plant-Based Insect Repellents Provide an Alternative to Synthetic Formulas. American Botanical Council. Retrieved March 22, 2023, from https://www.herbalgram.org/resources/herbalgram/issues/98/table-of-contents/hg98feat-insectrepellents/ 3. Du, E. J., Ahn, T. H., Choi, M. G., Kwon, I., Kim, H., Kwon, J. Y., & Kang, K. (2015). The Mosquito Repellent Citronellal Directly Potentiates Drosophila TRPA1, Facilitating Feeding Suppression. Molecules and Cells, 38(10), 911–917. https://doi.org/10.14348/molcells.2015.0215 4. Uenoyama, R., Miyazaki, T., Hurst, J. L., Beynon, R. J., Adachi, M., Murooka, T., Onoda, I., Miyazawa, Y., Katayama, R., Yamashita, T., Kaneko, S., Nishikawa, T., & Miyazaki, M. (2021, January 22). The characteristic response of domestic cats to plant iridoids allows them to gain chemical defense against mosquitoes. Science Advances. Retrieved August 7, 2023, from https://doi.org/10.1126/sciadv.abd9135 5. Plants for Pollinators advice and downloadable lists. (n.d.). Royal Horticultural Society. Retrieved March 22, 2023, from https://www.rhs.org.uk/science/conservation-biodiversity/wildlife/plants-for-pollinators 6. Benjamin, A. (2020, July 12). Making a beeline: wildflower paths across UK could save species. The Guardian. Retrieved March 22, 2023, from https://www.theguardian.com/environment/2020/jul/12/making-a-beeline-wildflower-paths-across-uk-could-save-species
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6 Ways To Get Rid Of An Ants’ Nest In Your Garden (And Why You Should Think Twice)
IN THIS GUIDE Are Ants In The Garden A Problem? Ants – A Balanced View When To Get Rid Of An Ants’ Nest Facts To Bear In Mind 1) Boiling Water 2) White Vinegar 3) Diatomaceous Earth 4) Boric Acid & Sugar 5) Nematode Steinernema feltiae 6) Ant Bait Stations Goodbye Garden Ants! References It is not exactly unusual to have ants, or even an ants’ nest, in your yard. In fact, ants perform multiple beneficial functions in the garden. That said, there are some legitimate reasons to eradicate an ants’ nest, particularly if you have a problem with aphids or similar pests. We lay out half-a-dozen methods, from plain old water to highly-technical nematode release. Are Ants In The Garden A Problem? So you have an ants’ nest in your garden. Before you go ballistic and take out the heavy artillery, let’s take a minute or two to evaluate whether the ants are an actual problem and need to be taken care of, and, if so, choose a solution that fits the scale of the problem and will do no or minimal collateral damage. Ants in the yard are, well, normal. That doesn’t mean you have to have them in your garden if you don’t want to, it’s just to get across that there’s nothing particularly unusual about having ants in your garden. You may be concerned because you know about an ants’ nest in your garden. But many, many homeowners have ants’ nests in their respective gardens – but they don’t even know about the problem and so the ‘problem’ is not a problem. So where an ants’ nest is concerned, perhaps ignorance is bliss. If you know you have an ants’ nest in your garden, we’d recommend you only get rid of it if you also know that the ants are damaging your garden. Ants – A Balanced View The purpose of this article is not to elaborate upon the benefits that ants can and do bring in the garden. However, so that you can make a fully informed decision as to that ants’ nest, before we proceed to outline the ways to get rid of it, a concise outline as to the beneficial effects of these tiny insects. Ants, as such and under normal circumstances, are not garden pests. For the most part they are teeny-weeny ‘garden hands’. To begin with, they are natural-born tillers of the soil. Their incessant subterranean activity results in particulate matter from the surface being pulled underneath, deep down, and vice versa, improving the fertility of the soil.1 Also, their tunnelling into and through the soil aerates it which assists in the decomposition of organic matter – dry leaves and dead earthworms alike. Though ants are scavengers in the main, many UK species are also predators. Many, if not most, species of ants actually control or reduce the population of garden pests because they prey on their larvae and eggs.2 Ants are territorial insects so as long as your garden has one ant colony you won’t be getting another one unless an invading troop attacks and defeats the resident ants.3 On the other hand, if you destroy or ‘evict’ your garden’s resident ants, then sooner or later advance scouts or a roaming ant colony will come upon your yard, see it as virgin territory ripe for occupation, and lay down stakes! Also keep in mind that ants play a part in a healthy garden ecosystem. While they prey on various small garden pests, they themselves are preyed upon by small birds, fish and other insects. Getting rid of an entire ant colony can throw that healthy garden ecosystem out of whack. Believe it or not, there are yet more reasons to tolerate an ants’ nest in the yard but, like we said, this article is not about the positives of ants in the garden! “I have never had to eliminate an ants nest as a horticulturist,” shares Master Horticulturist Colin Skelly. “Nests would rarely be large enough to cause a problem in the garden in the UK context. “The only time I have removed an ants nest would be when they have become a problem in the built environment, particularly entering kitchen spaces to take advantage of a supply of crumbs, sugar, etc.” When To Get Rid Of An Ants’ Nest So why, under what circumstances, would it be the right decision to get rid of an ants’ nest? First – are the ants ruining your landscaping and depositing piles of soil on the lawn? Is the ants’ nest tucked away by the fence or is it an eyesore? Is it getting bigger and bigger? If the answers are ‘Yes,’ the affirmatives answer the bigger question too. Second – if the ants’ nest is near shrubs and plants that have delicate roots or those that are wilting without any discernible reason, then the ants’ nest may have to go. Though subsoil ant activity is a good thing in general, when it is below or beside delicate roots, it can disturb them and affect their uptake of soil nutrients. Third – does your garden have an aphid problem that you can’t get under control? Or a mealybug or whitefly problem? If yes, then you may need to get rid of the ants’ nest. That’s because ants and aphids often work together; they have a symbiotic relationship. Just as supply ships victual the Navy while being protected by destroyers, so do aphids provide food to ants, and in turn are protected by them. The same goes for mealybugs and whiteflies. Concisely, aphids, mealybugs and whiteflies as honeydew-producing garden pests are of value to ants because these pests provide sustenance to ants: ants gather the honeydew that these pests secrete and take it to their nest, mainly for the queen but also for the colony.4 This means that if you release ladybirds or lacewings to destroy aphids, mealybugs or whiteflies, your efforts may come to naught because the ants will protect the garden pests (as they are well known to do). If you make the decision to destroy an ants’ nest, be aware that its actual size underground will be far larger, probably some multiple, of the size you may estimate by what is visible on the surface. Facts To Bear In Mind There are 51 native ant species in the UK.5 The most commonly found ones are black ants (Lasius niger), yellow meadow ants (Lasius flavus), red ants (Myrmica rubra) and wood ants (Formica rufa). These different ant species have different levels of resistance and susceptibility to the ant-control methods outlined underneath. Therefore, if one method does not work, do not be discouraged but try another one. Avoid trying to mix and match methods as one method may attenuate the efficacy of the other – choose one method and stick with it until it succeeds or fails. Most of the well-known commercial insecticides and applications for reducing the presence of ants are formulated for use in dwellings and other buildings. These are not meant for use in the garden and may well cause damage to plant life. Also, though these applications will certainly kill ants in exposed locations then (except for ant bait stations) they will not be of any effect in eliminating an ants’ nest. 1) Boiling Water Boiling water is a well-known ant-killer but, for obvious reasons, this is not a solution for the lawn or close to plant life. If the ants’ nest is a metre or so away from the lawn or from the estimated extremity of the root system of the nearest plant, pour boiling water – bucketfuls – on the nest and into all the holes you can see; if not, then douse the ants’ nest with bucketfuls of cold water every day or two (unless succulents or such are nearby!). You could also run water – lots of it – through the hosepipe and jet it into all the entry/exit holes that you can spot. Ants dislike damp conditions, and may soon decide to shift to a more congenial neighbourhood. 2) White Vinegar White vinegar is another well-known ant-killer which – unlike boiling water – will not harm plant life. It is the mild acid in white vinegar that is the knockout agent. How, though, to deliver the vinegar where it counts – in the nest? Fill a jet washer or jet spray machine with white vinegar and shoot it into the ants’ nest’s entry holes. If you cannot spot them, then spray it all around the ants’ nest, surrounding and soaking it with white vinegar. You will have to do this several times but the net result will be the elimination of nearly the whole colony with the survivors hightailing it for less inhospitable nesting grounds. 3) Diatomaceous Earth Sprinkle food-grade diatomaceous earth all around the ants’ nest, especially where you spot the entry holes. Try to get it inside of the holes. Diatomaceous earth will kill the ants, but there’s a catch: it will also kill other insects and may also kill small garden life like amphibians. That is because the microscopic razor-sharp edges of diatomaceous earth abrade insect exoskeletons and also dehydrate insects and small animal life.6 Damp and wet conditions greatly degrade the potency of diatomaceous earth so be sure to use it when the earth and the weather are both dry. This ant control technique is in the main an effective one for all types of ants and though it will not eliminate an ants’ nest it will at least keep reducing the ant population. 4) Boric Acid & Sugar This is the original ‘bait station’ technique that has been used by farmers and country gardeners for generations. Do not use this method in conjunction with any other. Make a mixture of sugar (preferably icing sugar) and boric acid powder in a ratio of 8 parts sugar to 1 part boric acid. Mix this in bottled water so as to form a gooey liquid with the consistency of treacle or honey. Do not use tap water as impurities in it could put off the ants from consuming the bait – or the minerals or ions in tap water could react with the boric acid and neutralise its potency. Drop and spread this thick gooey concoction on and around the ants’ nest, particularly at the holes. Keep doing so every couple of days. Worker ants will take this toxic mix into the nest for the queen and the rest of the colony. 5) Nematode Steinernema feltiae Steinernema feltiae are microscopic organisms that act as a ‘slow poison’ on an ant colony. These nematodes enter the insects’ body cavities and then release bacteria, which destroy tissue and poison the ants.7 The variables are that there are a few different brands of this nematode and several different species of ants. One brand may deliver excellent results with one species while failing with another species. These nematode formulations have to be used within a week or two of delivery, have to be mixed very precisely with water, and must not be applied in sunlight or under extreme temperatures. Also, they are most effective between April and September. One plus point of this method is that these nematodes act against most pests that are destructive to plant life but are harmless to beneficial predators as well as to plant life. 6) Ant Bait Stations Ant bait stations are so constructed that ants, attracted to the enticing bait inside the plastic structure, can get in and out while other soil-dwelling insects are either not interested or cannot enter the precisely-fabricated station. Worker ants collect the toxic bait, usually in gel form, and take it back to the nest for the queen and the rest of the colony.8 As the appetising bait contains some or another potent poison, the ants start to die. The few ants that remain cannot sustain the colony, which collapses. Bait stations can be placed by the entry holes of the nest or along foraging pathways. Goodbye Garden Ants! Eliminating an ants’ nest is not an exact science (and it is certainly not an art). It is a trial-and-error process. If you have decided to get rid of an ants’ nest, the important thing is to approach it as a difficult project that will require sustained work. As a last resort, you can call in professional exterminators but do not get discouraged too quickly, and be persistent. References 1. Farji-Brener, A. G., & Werenkaut, V. (2017). The effects of ant nests on soil fertility and plant performance: a meta-analysis. Journal of Animal Ecology, 86(4), 866–877. https://doi.org/10.1111/1365-2656.12672 2. Ye, Y. (2019, March 12). Ant larvae defend their homes by eating eggs laid by intruders. New Scientist. Retrieved June 3, 2023, from https://www.newscientist.com/article/2195765-ant-larvae-defend-their-homes-by-eating-eggs-laid-by-intruders/ 3. Hölldobler, B., & Lumsden, C. J. (1980). Territorial Strategies in Ants. Science, 210(4471), 732–739. https://doi.org/10.1126/science.210.4471.732 4. Farmer ants and their aphid herds. (n.d.). McGill Office for Science and Society. Retrieved June 3, 2023, from https://www.mcgill.ca/oss/article/did-you-know/farmer-ants-and-their-aphid-herds 5. Ant recording and identification. (n.d.). NatureSpot. Retrieved June 3, 2023, from https://www.naturespot.org.uk/ant_recording_ID 6. Zeni, V., Baliota, G. V., Benelli, G., Canale, A., & Athanassiou, C. G. (2021). Diatomaceous Earth for Arthropod Pest Control: Back to the Future. Molecules, 26(24), 7487. https://doi.org/10.3390/molecules26247487 7. Insect-Parasitic Nematodes for the Management of Soil-Dwelling Insects. (n.d.). Penn State Extension. Retrieved June 3, 2023, from https://extension.psu.edu/insect-parasitic-nematodes-for-the-management-of-soil-dwelling-insects 8. Tips for Effective Ant Baiting. (n.d.). NC State Extension Publications. Retrieved June 3, 2023, from https://content.ces.ncsu.edu/tips-for-effective-ant-baiting
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Overgrown Ivy Can Become Problematic - Consider These Ideas To Control Its Growth
IN THIS GUIDE How Does Ivy Work? Tolerating Ivy When Ivy Becomes Problematic First – How Not To Get Rid Of Ivy How To Kill Overgrown Ivy Advice From A Master Horticulturist References Ivy is famous for its ability to climb, whether on rocks, structures, or even other trees. The roots of the word ivy come from a proto-Indo-European word that translates as “to grasp”, making it a very good and apt description of the plant’s tendency to take hold and go wild. Ivy is prone to grow in a surprising array of places How Does Ivy Work? Ivy grows on the ground until it finds a suitable surface to climb. At this point, a surprisingly complicated process kicks into action. For many years botanists thought that ivy created a glue-like substance to attach itself to surfaces, but it actually goes a lot deeper.1 Firstly, the plant comes into contact with the surface it will climb. Then, the roots change shape to fit the surface. At this stage, the roots aim to expand outwards as much as possible; increasing the amount of contact they have with the surface in question. Then, a glue-like substance is excreted, and small hairs on the root fit into tiny holes on the surface. When they dry out, they scrunch up and lock themselves firmly into the crevice. With this process taking place many times on each surface, ivy builds a strong attachment that can be hard to dislodge. Because of the way the mechanism works, it keeps a strong hold even when the plant is dead, too, meaning that you can’t simply kill the plant and pull it down. So, with that in mind, you may be wondering how to kill and get rid of overgrown ivy? Tolerating Ivy Let’s start with something a little less drastic. Here we’ll outline the times and places that ivy can be tolerated. The first step here is busting the myth that ivy strangles the trees it grows on, hindering their ability to grow. It doesn’t.2 Unlike parasitic plants like mistletoe, ivy only uses trees for support, rather than penetrating their bark and leeching resources.3 Ivy has its own root system beneath the ground, and gets the water and nutrients it requires from there. So seeing ivy crawling up a tree trunk isn’t an automatic cause for concern. Instead, keep an eye on things and see how they progress. When Ivy Becomes Problematic If ivy starts to smother a tree trunk or prevent light from making its way through the canopy, it can be problematic. This can hinder the photosynthesis of the leaves whose light is being blocked, which prevents the tree from generating its required nutrients. It can also be an issue when it comes to evaluating a tree for safety, as ivy can cover up structural damage, making it harder to see what’s going on underneath. If you’ve got ivy growing on an old tree that’s more prone to damage, you may want to consider removing it so that the tree’s health can be accurately assessed. Ivy also has the potential to hold fungal spores that may cause damage to the tree underneath. Some rodents and pests shelter in ivy as well, leading to another potential source of strife for the tree. First – How Not To Get Rid Of Ivy One thing you should never do is just grab ivy from a tree trunk and give it a good, hard yank. As we mentioned earlier, ivy has a very sophisticated means of attaching itself to surfaces, meaning that if you just grab and pull, it’s quite likely that you’ll strip some of the bark along with the ivy. Removing bark from trees exposes the tissue underneath, making it much more vulnerable to attack and infection. See how many different attachment points there are? If you’ve got ivy that you’re concerned is causing damage and needs to go, here are a few ways to remove it. How To Kill Overgrown Ivy The steps for removal differ slightly depending on where the ivy is growing. In this section, we’ll give instructions for removing ivy on walls, trees, and the ground. Ivy Growing On Walls We’ll start by emphasising that ivy doesn’t cause damage to sound masonry. This means that if your brickwork is in good condition, the mechanism ivy uses to cling and grow will not cause damage. If this is the main reason you’re considering removing the ivy, you may want to reconsider. If not, here’s what you need to do – Try non-weedkiller control methods first, as they’re usually more forgiving on the environment. Cut stems back as close to ground level as possible, and dig out the woody stump at the base of the ivy plant. This isn’t always possible; it depends on where the ivy is growing. If you can’t get to it, trimming can help keep things is in check but is unlikely to kill the plant. If this doesn’t work, sever the stem and use a weed killer designed specifically for stumps and roots. Often these are based on chemicals like glyphosate or triclopyr. Be careful when using weedkillers as the chemicals involved are very potent. When the ivy has been successfully killed, you can peel the plant from the walls and surfaces it’s grown on. Again, be careful as the tendrils are still anchored in fairly firmly. Pull gently and don’t be afraid to switch to a brush or scraper if needed. Ivy Growing On Trees The steps are largely the same, except with the caveat that you shouldn’t pull the dead ivy away. If you’re not concerned about the aesthetics of the dead ivy you can leave it on the tree, safe in the knowledge that it won’t cause any more problems. Overgrown Ivy On The Ground Ivy is an enthusiastic grower on the ground as well as up vertical surfaces. If you’ve got ivy crawling around at ground level and you’d like to keep it in check, here’s what to do – Dig up as many of the stems and as much of the root as possible. Take a look at the weedkillers mentioned above, taking special care not to let other plants come into contact. You can ruffle the ivy leaves with a rake or similar tool to damage their surface, giving weedkiller more of an opportunity to soak through (the leaves in their natural state are quite lacquered, making them fairly resistant to moisture). If the ivy is growing in a spot you’re not planning to use for growing other plants, you can cover it over with carpet or a thick layer of bark mulch for a couple of growing seasons. This will prevent the plant from getting the sunlight it needs to survive, ensuring a slow but certain death. Ivy at ground level is attractive but relentless Saltwater & Duct Tape One method for killing ivy that you’ll see mentioned fairly often is to slit the root, then use duct tape or similar waterproof tape to create a cone-like structure around it. With the slit contained you can pour saline solution (water + salt) into the cone, which will gradually enter into the root system and damage the ivy. Simultaneous and repeated applications of this treatment can eventually kill the plant. Advice From A Master Horticulturist One of the most important things to keep in mind with ivy is that often, it isn’t causing as much damage as you might initially think. The common misconception that ivy strangles trees and drains their nutrients, for example, is wrong. It’s only if ivy is growing on masonry in poor condition, or if it’s threatening gutters or similar accoutrements. So, if you’re considering killing ivy, take a step back first to evaluate whether it’s really the best course of action. “Ivy is a valuable resource for garden life, both as habitat and as a source later summer flower resource for pollinators,” says Colin Skelly, a Horticultural Consultant. “The approach I take is to manage ivy growth. Allowed to run its course, it can add to the wind ‘sail’ of a tree or shrub in winter, and when removed it takes away a valuable resource for garden wildlife. “I seek to sever the stems of one-third of established stems as close to the base of trees and shrubs as I can. “I don’t poison as it will take some time for the ivy to re-establish significantly. This achieves a balance between controlling a potential problem and retaining a resource for wildlife.” Whichever method you go for, we hope that this guide has been useful in helping you to conceptualise the problem and find the right answer. References 1. Roots Attach Firmly: English Ivy. (n.d.). AskNature. Retrieved March 17, 2023, from https://asknature.org/strategy/roots-attach-firmly/ 2. Patch, D. (n.d.). Ivy: Boon or Bane? Trees in Focus. Retrieved March 17, 2023, from https://www.trees.org.uk/Trees.org.uk/files/f0/f0e3a76b-926f-4cde-b703-417563ae93df.pdf 3. Ivy (Hedera helix) – British Wildflowers. (n.d.). Woodland Trust. Retrieved March 17, 2023, from https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/plants/wild-flowers/ivy/
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You Can Use Bleach To Kill Weeds, But That Doesn't Mean You Should - Here's Why
IN THIS GUIDE Finding The Right Solution Can You Use Bleach To Kill Weeds? Bleach Does Kill Weeds: Here’s How What About Bleach For Patios & Places With No Soil? Bleach In Your Garden: Horror Stories Killing Weeds With Bleach: The Verdict References There’s nothing quite as frustrating as weeds. Whatever you do, however much back-breaking manual labour you put in, their persistent green selves will always find a way back into your garden. It’s an ongoing war of attrition where the closest you’ll ever get to victory is holding slightly more of them at bay for slightly longer. As a gardener, it’s likely you know this pain fairly well. Finding The Right Solution It’s also fairly likely that you’ve considered whether the weapons in your anti-weed arsenal are really strong enough to do the trick. You’ve covered beds for the winter before growing season to kill off as many as possible. You’ve forked the soil to remove the most persistent contenders. How do you get rid of the confounded things?! Maybe you’ve even picked out a few by hand: adding the sweat from your brow to the toolkit. Perhaps you’ve also considered the nuclear option. Can You Use Bleach To Kill Weeds? If you’re at the end of your gardening tether, you may be looking for something a little more extreme than the techniques you’ve employed so far. And while you can use bleach to kill weeds, as organic gardeners we strongly advise that you shouldn’t. “I cannot stress enough: you should not use bleach in the garden!” says Dan Ori, Master Horticulturist. “The potential danger to you and damage to your garden is massive. “I have never and will never use bleach (Sodium hypochlorite) in the garden, as the long-lasting negative side effects and wider environmental impact can be extremely high.” Bleach causes damage to the soil that can take a long time to correct itself, and there are safer alternatives available. Bleach Does Kill Weeds: Here’s How In the same way that bleach is harmful to humans and pretty much every living creature we share the planet with, it’s also harmful to plants.1 When bleach soaks into the soil, it makes its way down and kills the plant from the roots upward. Here’s the kicker, though. Because the pH level of bleach is so high, it makes the soil very alkaline. As most plants have very specific pH ranges at which they can grow, bleached soil isn’t conducive to plant life or growth, as the high alkaline levels prohibit plants from absorbing the nutrients they need to thrive.2 And as a gardener, this is probably reason enough in itself not to slather your garden with the stuff! Also, a by-product of bleach breaking down is salt, which isn’t a good addition to soil.3 There’s a reason why armies salted the earth behind them when they conquered a city: salt attacks plants via osmosis, sucking the moisture from them and slowly killing them. So, while bleach will be effective against common weeds, the collateral damage really isn’t worth the risk. And while it works on small weeds, it’s unlikely to make a dent on bigger weeds with dense root systems. When you consider this fact, it makes bleach an even less viable option for evacuating pesky weeds from your outdoor space. What About Bleach For Patios & Places With No Soil? Maybe you’re wondering about using bleach to remove weeds from the cracks between paving stones on your patio, or somewhere else in your garden that doesn’t have soil. In this instance, we’d still recommend using a product that’s designed specifically for this purpose. Although you’re not applying bleach directly to the soil, it’s not hard to see how it could make its way there eventually. When it rains, for instance. Or even as the residue trickles along channels in the slabs. There are more environmentally-friendly alternatives to consider: Sprinkle baking soda over your patio, sweep it into the cracks with a broom, then add water Use your hands! It’s not fun or particularly glamorous, but it’s an effective way to get rid of them Use special tools designed for narrow spaces. If you can’t fit your fingers into thin crevices between stones, use a tool made for the job Use boiling water. While this method definitely can (and will) kill any other plants and creepy crawlies it comes into contact with, it at least won’t cause lingering damage to the soil As you can see, there are plenty of viable options to consider before thinking about bleach. Bleach In Your Garden: Horror Stories Read around garden forums and you’ll find all sorts of stories about reckless neighbours washing their driveways with generous helpings of bleach, only to end up killing off the carefully tended flowerbeds of nearby homes. If you’ve been investing time and effort into your garden for many years, there’s nothing quite as soul-destroying as having your work destroyed by such an easily avoidable outcome. There are also stories of spouses enthusiastically cleaning their garden furniture, only for their partner to find all the nearby flowers dead the next time they head outside to water them. Whichever side of these potential situations you’re on, hopefully you can see why using bleach in your garden isn’t the best idea. It’s more than likely that you’ll kill at least something you didn’t intend to, whether it’s your own plants, your neighbour’s plants, or your partner’s respect for you. “There better not be any bleach in that bucket, Ian!” Killing Weeds With Bleach: The Verdict In this article, we’ve tried our best to outline the information around using bleach to kill weeds in your garden. Our goal has been to show that while you can use bleach in your garden, you probably shouldn’t. Better alternatives are available, and the amount of damage you risk causing to other plants, creatures, and ecosystems just aren’t worth it.4 In short: if you’re looking for effective ways to kill weeds in your garden, there are plenty of steps you can take before needing to consider bleach warfare. References 1. Benzoni, T. (2022, October 16). Bleach Toxicity. StatPearls – NCBI Bookshelf. Retrieved March 13, 2023, from https://www.ncbi.nlm.nih.gov/books/NBK441921/ 2. Effect of Soil pH on the Growth, Reproductive Investment and Pollen Allergenicity of Ambrosia artemisiifolia L. (n.d.). Frontiers. Retrieved March 13, 2023, from https://www.frontiersin.org/articles/10.3389/fpls.2018.01335/full 3. Ono, M. (n.d.). Everything You Always Wanted to Know About Bleach But Were Afraid to Ask. News & Views. Retrieved March 13, 2023, from https://www.scripps.edu/newsandviews/e_20060213/bleach.html 4. Beirne, P. (2020, May 26). How Bleach Damages the Environment and Our Health. Public Goods. Retrieved March 13, 2023, from https://blog.publicgoods.com/how-bleach-damages-the-environment-and-our-health/
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These Are The Signs Of Box Blight: Act Quickly To Save Your Plants Says Darren Lerigo
IN THIS GUIDE What Is Box Blight? Identifying Box Blight Preventative Measures Avoid Introducing It Into Your Garden Create Less Favourable Conditions Treating A Minor Box Blight Problem Treating A Major Box Blight Problem Buxus Alternatives References Box blight is a fungal disease that can pose major problems for gardeners with box hedges. In this article, we will introduce this common problem, and talk through what you can do to deal with this issue in an organic garden. What Is Box Blight? Box blight is a fungal infection which impacts box hedges or topiary. Two genetic types of fungus called Cylindrocladium buxicola are responsible for this problem.1 In an organic garden, you will obviously avoid the use of synthetic fungicides, but in any case, fungicides alone are rarely able to cure the problem.2 Box blight can be a serious problem, and it is important to remain vigilant. The sooner you spot the problem, the more likely it is that you will be able to save your plants. Box blight is the most serious of a number of infections which can present problems for box. However, all is not lost – the good news is that box blight does not affect the plant roots, only the above-ground growth. Identifying Box Blight First things first, it is important to be able to spot box blight and identify it correctly. When buxus is infected with box blight: Spots will appear on the leaves. Leaves turn brown and fall off, leaving bare patches. Black streaks and dieback will be visible on the stems. In wet conditions, you may also be able to see white spore masses of the fungus under infected leaves. Another fungal disease, Volutella blight, may initially be confused for box blight. This too leads to twig and leaf dieback – but black streaks characteristic of box blight do not form and the shrubs will not typically lose their leaves with this infection. One other key way to tell box blight apart from this somewhat less serious problem is that in the case of Volutella blight, the fungal spore masses under the leaves will be pink and not white. Preventative Measures While you can often rescue buxus which has a box blight infection, of course prevention is better than cure. Box blight spreads very easily, and can still arrive in your garden in spite of your best efforts. But there are certain things you can do to make it less likely that box blight will arrive, reduce the chances of it taking hold, and make it easier to manage the problem if it does. “Mulch, cut your plants down less and make sure you clean your tools whenever dealing with your plants,” suggests Darren Lerigo, a member of the European Boxwood and Topiary Society. Avoid Introducing It Into Your Garden Quarantine box coming from garden centres If planting box, choose somewhat more resistant varieties. All Buxus ssp. are susceptible to box blight and none are highly resistant. However, B. microphylla varieties are generally less susceptible than B. sempervirens. Common box and its dwarf form B. suffruticosa are extremely susceptible. ‘Faulkner’ is one variety available in the UK that is said to be somewhat more resistant. Make sure you quarantine new box plants for four weeks to make sure they are free of infection before you introduce them to your garden. Ideally, avoid the risk of importing new plants by propagating healthy plants in your own garden rather than buying additional plants. Sanitise tools, equipment and garden wear to make sure you do not spread disease from one area of your garden to another. (Box blight will likely have already been present for some time before symptoms emerge, so practice good garden hygiene even if you have not yet spotted an infection.) If you have a gardener then it is important to make sure they do the same, and are not spreading infection between gardens. Make sure people come into contact with box as little as possible. Especially in areas with visitors, place box topiary where it is not brushed past or handled so frequently. Make sure paths are wider where lined by box hedges to reduce human contact. This also improves airflow. While blight can still arrive in your garden, taking these steps will help manage the risk and could keep your garden box blight free. Create Less Favourable Conditions Diversify – avoid planting very long box hedges that the disease can move along. And do not surround box topiary with box hedges. Separate areas of box with other planting. Plant box in well-ventilated areas, free from damp and shade where the fungus will thrive. Plant box avoiding overcrowding between it and other plants, and increase plant spacing when placing the box itself for better airflow. Water early in the day if possible. And avoid watering from overhead to make sure the foliage does not get as wet. Mulch under the box plants to cover fungus inoculum and reduce the chances of fungal spores splashing up from the soil onto the leaves. Prune box to increase the distance between leaves and the ground. And trim to create hedges etc. with convex rather than flat tops. (For better water runoff which may help reduce the severity of box blight.) Always undertake pruning and trimming in dry weather conditions. Trim/ prune less frequently (for lower density and more open structure). Feed plants moderately, and not with a high nitrogen feed. Choose an organic formulation specifically for box for optimal plant health. Treating A Minor Box Blight Problem If you do see box blight in your garden, you must deal with the problem as soon as possible. The quicker you are able to tackle the problem, the more likely it is that plants can be saved and the easier containment will be. If you spot box blight: Remove all affected sections from the plant, cutting back to healthy growth, and a little further. Clear up all plant matter and surrounding debris. You might use a vacuum cleaner to suck up all leaves that fall to the centre of the plant where branches are too dense to access these easily. Scrape off all existing mulch and the surface of the topsoil where fungus is harboured. Bag up all this material and dispose of it carefully. Take great care not to spread the infection to other parts of your garden, and keep material clear of your composting system. Sterilise all tools, shoes and clothing so you do not spread the fungus to other parts of the garden. Add a new soft, natural mulch (Topbuxus carpet, for example) around the plants. Fertilise plants with a multi-purpose of Buxus-specific organic plant feed to promote healthy new growth. The healthier the plants are, the easier it will be for them to stave off infection. Since it is likely that other areas not yet showing symptoms will be affected, you will probably not immediately eradicate the problem, but you can reduce spreading. You can also repeat this process as and when other symptoms show. Treating A Major Box Blight Problem Unfortunately, sometimes a major box blight problem can set in before gardeners are aware of the problem. In some cases, it may be best to cut your losses and remove the affected plants entirely. However, in many cases, even a box hedge or piece of topiary with many affected areas can still be saved through careful and yet rather drastic action. Hedges and parterres of box can sometimes be saved by reducing height by around half, and perhaps width as well – cutting back to a few centimetres below any black streaks on stems and as above, carefully bagging and removing affected material. This includes dead leaves inside the plants, mulch, leaves on the ground and the top layer of soil. As above, hygiene is crucial, and great care should be taken not to spread the disease. Again, promote healthy recovery by mulching, and feeding with an organic plant feed suited to box. Remain vigilant for further signs of infection. In some cases, even chopping back this much may not be sufficient. With severe cases, you may need to take more drastic action to save prized box plants. In this case you might: Cut back all plants showing symptoms right down to ground level, leaving just the stumps. And clear up, mulch and fertilise as above. Buxus Alternatives Euonymus fortunei In areas where box blight is a major problem, or where serious outbreaks have already occurred, it is usually easier to forgo box altogether. When choosing new plants, or replacing box, it is best to choose alternatives rather than struggling on. “Despite my best efforts, Box blight repeatedly ravaged the box hedge in my vegetable garden,” shares Colin Skelly, a Horticultural Consultant and Professional Gardener. “I replaced it with Lonciera nitida, which is functional but does not match the attractiveness of Box and needs cutting several times during the growing season.” Some other options include: Berberis ssp. Euonymus fortunei Ilex crenata Lavandula angustifolia Lonicera nitida Osmathus delavayi Pittosporum ssp. Rosemarinus officinalis Santolina chamaecyparissus Taxus baccata References 1. Henricot, B., & Culham, A. (2002). Cylindrocladium buxicola, a new species affecting Buxus spp., and its phylogenetic status. Mycologia, 94(6), 980–997. https://doi.org/10.1080/15572536.2003.11833155 2. Box blight. (n.d.). Royal Horticultural Society. Retrieved April 25, 2023, from https://www.rhs.org.uk/disease/box-blight
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Identifying Vine Weevil: These Insects (And Their Grubs) Love Feasting On Plants
IN THIS GUIDE What Are Vine Weevils? What Do Vine Weevil Look Like? Which Plants Are Affected? Organic Vine Weevil Control Options 1) Boosting Biodiversity 2) Crop Rotation 3) Manual Removal 4) Biological Control References In this article, we explore the common garden pest vine weevil. We’ll discuss why these insects can be a problem and which plants might be affected, as well as what to do if you encounter this issue. What Are Vine Weevils? The scientific name for this insect is Otiorhynchus sulcatus.1 Extremely widespread and common, it is a beetle that feeds on a wide range of plants.2 The adults of the species eat the leaves of plants during the spring and summer months, whilst the grubs are active over the autumn and winter months, and feed on plant roots, weakening and sometimes even killing them altogether. What Do Vine Weevil Look Like? Adult vine weevils are just under 1cm long.3 They are a dull black colour, with smutty yellow marks on their wing cases. Even if you do not spot the vine weevils themselves, you may see signs of their feeding. When adult vine weevils have eaten parts of a plant, you will see irregularly shaped notches on the leaf margins during the summer months. Vine weevils usually grow to around 1cm long. If you have a container plant that wilts and you do not know why, it may be a result of these grubs eating the roots of the plant. Remove the plant from the pot and you will quickly see from the presence of the white grubs where this is the case. Note – there are other weevils that can cause similar damage as adults, but the other species are usually less problematic at the grub stage. Which Plants Are Affected? Vine weevils, as mentioned above, feast on a wide range of plants, including but not limited to: Strawberries Potatoes Tomatoes Cabbages Beetroot Carrots Radishes Spinach & other leafy greens. So they can be a particular problem in an edible garden. They can also be a problem in other parts of the garden, and some other plants particularly affected include: Primula Polyanthus Fuchsia Sedum Heuchera Hosta Epimedium Bergenia Rhododendron Evergreen Euonymous Hydrangea Young yews But remember, almost any plant can be susceptible, especially if it is grown in a container. Organic Vine Weevil Control Options Vine weevil can become a really annoying problem if their populations get out of control. As such it is best to act pre-emptively if possible, to avoid the issue occurring in the first place. If you do encounter this pest, it is something that you should be sure to get on top of as quickly as possible. Each of the options below should be concurrently for the greatest impact – 1) Boosting Biodiversity As with most pests in an organic garden, the best way to deal with pests is to ensure that the ecosystem is in balance. In a balanced ecosystem, pest populations are far less likely to reach worrying levels. The route to achieving good balance in the garden ecosystem is simple – make sure that there is as much natural biodiversity as possible. This means making sure that you include a diverse range of plants which interact beneficially with one another. And it means attracting as much wildlife as possible, and welcoming it into your space. When it comes to vine weevils, there are certain species that you will want to focus on attracting to your garden to keep their numbers down. Predators for vine weevils include: Hedgehogs Shrews Frogs Toads A wide range of birds Ground beetles Rove beetles Creating hedgehog habitats, hedgehog pathways and tunnels, and hedgehog houses can attract these mammals to your garden. You should also, of course, make sure that there are plenty of insects around for them to eat. Diverse planting schemes should also attract other wildlife too, including other mammals and a range of birds. A wildlife pond is great for amphibians, of course. And you should be sure to leave brush/log piles and other undisturbed areas for beetles and other bugs. When choosing plants for your garden, it is worthwhile considering that certain companion plants are anecdotally said to keep vine weevils away from the plants that are susceptible to them. Some people say, for example, that alliums or bay leaves may help keep them away. 2) Crop Rotation In your vegetable garden, avoid growing plants susceptible to vine weevil attack in the same area year after year. Crop rotation is a practice that will help to safeguard your crops from a wide range of pests and diseases that can build up in the soil. In particular, make sure that you have a three or four year crop rotation plan in place for brassicas (members of the cabbage family), root crops, Solanaceae (tomatoes, potatoes etc.) and legumes. 3) Manual Removal If you have a problem with vine weevils in container grown plants, especially if they are indoors or grown in a greenhouse or polytunnel, the above may not be a huge amount of use to you. But that does not mean that you need to resort to extreme measures to get the problem under control. Often, manual removal of the adults, by hand, is all that is required. One mild evening in spring or during the summer, head out with a torch and take a close look at your plants and surfaces nearby. Simply pick off any adult vine weevils you see; shaking a shrub over a sheet can allow you to dislodge more from the plant that can also be collected. You can also look in hidey-holes (beneath plant pots or beneath staging in a greenhouse or polytunnel, for example) to find the hiding adults in their daytime hideouts. Sticky traps are also sometimes used to collect the adult vine weevils from around containers or on the staging in a greenhouse or polytunnel. But bear in mind that these can trap beneficial insect life too – so for a healthy organic garden, they should really only be used as a last resort in extreme cases. Of course, you should always clean out any containers or pots well, and can carefully dispatch or dispose of any grubs that you find in compost or potting mix. 4) Biological Control In cases where there is a severe infestation, you may also wish to consider a biological control. The nematodes Steinernema kraussei, Heterorhabditis megidis, H. bacteriophora and S. feltiae are considered to be effective when used against vine weevils in containers or in the ground. They are best applied when the soil or growing medium has reached the right temperatures for the nematodes to be effective, and before the grubs are big enough to do any serious damage. “Vine weevil can be a major problem for plants grown in pots in particular,” says Colin Skelly, a Master Horticulturist. “I have had to tackle them in nurseries and in living wall systems. Nematodes work very effectively but only when the soil temperature is optimal and when the pot compost is moist. “Too cold, too hot, too dry and the populations will not establish and parasitise the vine weevil larvae.” This is usually in around August or September. They are most effective in lighter, more friable soils and growing media, and can give poorer results when the soil is very dry, or very heavy. It is also possible to purchase a trap which contains a type of nematode (Steinernema carpocapsae). These are placed below plants in the summertime, and adults are killed when they enter during the day. References 1. Otiorhynchus sulcatus (vine weevil). (2022). CABI Compendium. https://doi.org/10.1079/cabicompendium.38071 2. Vine Weevil. (n.d.). NatureSpot. Retrieved March 27, 2023, from https://www.naturespot.org.uk/species/vine-weevil 3. Vine weevil (Otiorhynchus sulcatus) identification guide. (n.d.). Natural History Museum. Retrieved March 27, 2023, from https://www.nhm.ac.uk/take-part/identify-nature/common-insect-pest-species-in-homes/vine-weevil-otiorhynchus-sulcatus-identification-guide.html
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Bugs On Your Houseplants? Here's 6 Common Types To Help You Identify Them
IN THIS GUIDE Types Of Houseplant Bugs 1) Thrips 2) Leafminers 3) Beetles 4) Whiteflies 5) Spider Mites 6) Aphids Getting Rid Of Plant Pests Preventative Measures The Best Defence Is A Good Defence References Plenty of pests can wreak havoc on your carefully-tended houseplants. Such abuse is dispiriting and can cause untold, permanent damage to your plants but, thankfully, there are steps you can follow to remove and, more importantly, prevent such pests. Your beautiful houseplant is their tasty supper In this guide we’ll look at the most common houseplant bugs you’re likely to come across in the UK, steps to prevent them taking hold, and steps to remove infestations should they occur. Types Of Houseplant Bugs There are several main contenders – a variety of minibeasts that threaten UK houseplants with their presence. You may notice slugs and snails missing from our list. This is deliberate, as often these slimy fellows will stay outside. 1) Thrips What are they? Small insects that suck sap from the leaves of plants, leaving damage in their wake. What do they look like? Winged insects about 2mm long, with light hair on the wings. Likely colours include pale yellow, brown, or black.1 Signs of their presence: You’ll notice dull, discoloured leaves with black spots. White flecks on flowers can also indicate presence. 2) Leafminers What are they? A family of pests that burrow into leaves to get at the nutrients inside. Their presence looks worse than it is. What do they look like? Because there are so many pests in this category, appearance varies. Also, the damage they cause is a better diagnostic than the aesthetic qualities of the bugs themselves. Signs of their presence: Tunnel-like burrows on leaves, often brown, and possibly with black excrement left behind.2 3) Beetles What are they? Another vast family of insects containing hundreds of thousands of distinct varieties – some of whom like to live on and eat houseplants. What do they look like? Beetles have hard wing cases, a line down the middle, and antennae, but there’s so much variation between species that there’s no fixed answer for this question. Signs of their presence: Beetles will be visible to the naked eye, and will likely create holes in the leaves they feed on. 4) Whiteflies What are they? Sap-sucking flies damage plants by stealing their nutrients and leaving damaging excrement.3 What do they look like? Small and white, with translucent wings. Often you’ll see them in large groups. Signs of their presence: Easily visible clusters of flies, evidence of sticky and sugary excrement on leaves, general poor leaf health. 5) Spider Mites What are they? One of many mites feed on sap sucked from leaves. Over-feeding can cause leaf damage and death, if left unchecked. What do they look like? Small bugs, about 1mm in length, translucent bodies whose colour depends on the variety. Signs of their presence: Mottled leaves, white cast skins or egg shells visible, silk web on plants, and discoloured leaves. 6) Aphids What are they? Yet another sap-sucking pest whose colonies damage plants they decide to take up residence upon. What do they look like? Small and greeny-yellow, ranging in size from 1mm to just shy of a centimetre. There are many varieties, meaning exact size and colouration can vary.4 Signs of their presence: Visible clusters of insects, stunted growth, mouldy leaves, cast skins, and sometimes ants are an indication of aphids nearby (the two share a symbiotic relationship). Getting Rid Of Plant Pests Bugs are perseverant and tenacious, and they’ll probe for gaps in your defences no matter how well-laid they are. When this happens, you have to ramp up the attack. Here’s what to do. Make A Decision How attached are you to your infected plant? Although it may seem harsh, getting rid of plants you’re not overly attached to can often be the easiest way to resolve an infestation. If the thought of throwing your plant out fills you with rage, that’s a good indication that persevering with the following steps is the best course of action. If it doesn’t, consider getting rid and moving on. Isolate! As soon as you notice pests on a houseplant and you decide to save it, isolate the plant. Move it away from your other plants and keep them separate until you’re confident you’ve removed the problem completely. This step will prevent pests spreading themselves enthusiastically around all of your plants. Be Persistent Sadly, getting rid of pests can be quite a long haul, as they’re unlikely to give up their ill-gotten gains without a fight. Steel yourself and know that they will be gone eventually. Evaluate The Damage When pests take hold, they won’t necessarily infect the whole plant straight away. If some leaves are infected, remove and destroy them. Keep an eye on the plant for a couple of weeks afterward to see whether any lingering individuals establish another infestation: If so, repeat the process. Pick Off Any Pests That Are Big Enough Although it’s icky, manually removing pests is an effective way to reduce their hold on your houseplant. Pinch them gently and remove if they’re big enough. If not, use a cotton bud dipped in disinfectant, or tweezers, or something similarly able to scrape them away. Ideally you’ll want to squash the pests and throw them in the bin. A magnifying glass can help with this job Spray Your Plant With Non-Pesticides Spraying with water can help with physically removing pests, and mixing some insecticidal soap into the water can boost effectiveness. These soaps are available from gardening stores, and are specially formulated to discourage insects. “Insecticidal soap is the only method I use other than hand picking pests,” says Master Horticulturist Colin Skelly. “Observation is key and, if caught early, will work very effectively. Conditions in the home provide the conditions for houseplant growth but also for pest population growth, so timeliness is essential. “Repeat spray 2-3 times at 5-7 day intervals making sure to spray under leaves as well as on top and leaf axils.” Spray Your Plant With Pesticides If the previous steps haven’t helped to alleviate your infestation, more drastic measures must be taken. Pesticides are potent chemicals designed to kill and remove pests, but beware: Their potency increases the risk of damage to your houseplant. Always follow instructions and use pesticides carefully. There are various pesticides available, each intended for use with specific types of pest. For this reason we can’t include usage directions, but each product will include detailed instructions on the packaging. Make sure to follow these for safety reasons. Preventative Measures With most things in life, taking preventative measures is often more effective and painless than waiting until things hit a crisis point to take action. The same is true with preventing houseplant bugs. There are a few simple steps you can take to reduce the risk of infestation. Where possible, incorporate these into your regular plant-care routine. Hopefully pests will be discouraged and will turn their attention elsewhere, leaving your plants to thrive. Establish A Perimeter Pests are often brought in with plants, but they can find their own way in, too. If you have windows and doors open regularly to let fresh air in, try to use screens and barriers to keep pests out. Listen To Your Plants’ Needs Pests are most likely to take hold when your plant is vulnerable. Giving them the right amount of sunlight and water, and the right conditions to thrive, will help your plant to grow big and strong, thereby lowering the risk of infestation. Inspect Newcomers This point applies to plants you’ve just bought from a garden centre, and to those you’re bringing in from a summer spent outdoors. Both have the potential to bring pests from their old home and into yours. With plants that are new to you, check the entire plant for signs of pests. Give the leaves, stalks, and flowers a once over. If you find anything, keep the plant outside or in quarantine until you’ve taken eliminatory steps. For plants you’re bringing indoors after a summer outing, you’ll need to check the soil too. Opportunist pests can take root (pardon the pun) and sneak indoors to wreak havoc. Here’s what you’re looking for during an inspection – Pests hanging out on the bottom of leaves. They may be quite small, so a magnifying glass is helpful in spotting them early. Blemishes or mottling on leaves. Holes in leaves. Quarantine Keeping new plants away from others for a few weeks is a surefire way to ensure there are no pests. Sometimes an inspection like the one in the previous step will miss small or particularly well-hidden pests: Quarantine is a way to force them to show themselves before any other plants can be affected. Water The Soil, Not The Plant This ties back to our second point of listening to your plants’ needs. Sometimes when watering, people liberally apply water to the plant itself with the hope that it’ll trickle down into the soil. Where possible, avoid this. Especially indoors, where there’s less likely to be enough sunlight for the water to evaporate away. Moist, soggy leaves are an inviting prospect for pests, and represent an easily avoidable vulnerability. Water the soil directly, or bottom water by allowing water to drain up through holes in the bottom of your plant pot. Use Store-Bought Soil If you’re repotting, use bought compost rather than soil scooped up from your garden. This greatly reduces the chance of bringing in pests from tainted soil, and has the bonus benefit of ensuring more reliable nourishment for your plant. The Best Defence Is A Good Defence Remember, preventative measures are almost certainly more effective than remedial ones. Keeping your plants in good condition, respecting their needs, and taking steps to reduce the risk of infestation should hold pests at bay. If they do find their way in, whether through a window, on a new plant, or hidden deep in the soil, pests can be contained. While it’s frustrating and dispiriting, all that’s required is perseverance and the right steps taken at the right time. We hope our guide to the types of UK houseplant bugs and what to do about them has been useful. If you’re reading to learn how to remove an existing pest problem, we wish you all the best in doing so. References 1. What do thrips look like? (2011, November 18). The Australian Museum. Retrieved March 27, 2023, from https://australian.museum/learn/species-identification/ask-an-expert/what-do-thrips-look-like/ 2. Leafminers (vegetables). (n.d.). Wisconsin Horticulture. Retrieved March 27, 2023, from https://hort.extension.wisc.edu/articles/leafminers-vegetables/ 3. Whitefly. (2018, May 11). Agriculture and Food. Retrieved March 27, 2023, from https://www.agric.wa.gov.au/pest-insects/whitefly 4. Aphids. (n.d.). Wisconsin Vegetable Entomology. Retrieved March 27, 2023, from https://vegento.russell.wisc.edu/pests/aphids/
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A Horsetail Infestation Is Difficult To Control - Here Are 5 Solutions To Consider
IN THIS GUIDE What Is Horsetail? Why Is Horsetail Problematic? How To Identify Horsetail How To Control Horsetail 1) Removing Shoots 2) Mulch The Area 3) Mow Any Horsetail In Your Lawn 4) Digging Up As Much As Possible 5) Consider The Use Of Weed Killer Horsetail FAQs References Horsetail is an invasive weed that can cause a lot of damage and disruption in British gardens. Although it’s not an unattractive plant, horsetail has fast-growing underground stems which let it spread quickly and take deep hold, making it difficult to keep under control. We’ve written this guide for people facing a horsetail infestation. Our hope is that the information here will help you to get things under control again! What Is Horsetail? Firstly, it’s important to know that while horsetail and mare’s tail are often used interchangeably, they’re actually two distinct plants. Horsetail is Equisetum arvense, a perennial plant that grows on land. Mare’s tail, on the other hand, is Hippuris vulgaris, an aquatic plant. Horsetail is native to arctic regions and parts of the northern hemisphere. It’s actually considered a “living fossil” given that its relatives are estimated to have occupied the Earth around 350 million years ago!1 This perennial weed forms dense clusters of dark green foliage that can take resources and nutrients from other plants, causing damage. One of the main reasons the plant is so hard to control is that the roots (or rhizomes) can penetrate up to two metres below the ground! Far out of reach of most herbicides. The plant reproduces through its rhizome network or through spores, both of which make it tricky to control.2 When you’re dealing with a plant that can reproduce through sections of root that have been cut, it becomes more difficult to remove the plant entirely from your garden. Why Is Horsetail Problematic? To be considered a weed, a plant must be unwanted, hard to keep at bay, and in competition with desired plants for the resources and nutrition available in your garden. Horsetail ticks all of these boxes with vigour. Once established in your garden, horsetail has a tendency to crowd out other plants. Then, even when you cut it back or attempt to uproot it, there are rhizomes waiting deep underground, far out of reach, ready to rear their heads once again.3 Not only that: Because this plant burrows so deep, it’s able to spread between gardens far underground, beneath even the deepest of fences. In short, there’s good reason that horsetail is known as one of the most fearsome weeds we face in the UK! How To Identify Horsetail The first step in controlling and killing horsetail is making sure that you’re actually dealing with horsetail: Horsetail grows anywhere from 0.1-1m in height. The plant is characterised by side shoots that branch out from segment joints, and by spore cones with a distinctive brown colouration. These cones are about half a centimetre in diameter. How To Control Horsetail If you’re unfortunate enough to have a horsetail infestation, you have a few options. Note that some UK councils have reporting programs in place to monitor the presence and spread of horsetail in the local area. If you live in a place whose council collects this information, make sure to let them know.4 They may even be able to provide information or help with controlling the spread. 1) Removing Shoots The temptation when you see horsetail popping through the ground may be to cut it back. Try to resist this, if possible. Because of the deep underground rhizome network, cutting back at ground level can cause more harm than good, as cut segments can regrow into more weed, effectively compounding the problem. The Royal Horticultural Society (RHS) note that over a period of many years, trimming back surface-level horsetail may lower the severity of an infestation. However it’s not ideal as a solution in the short or long-term. 2) Mulch The Area Regular mulching is associated with reduced levels of horsetail, although as with removing shoots, this must be done on a long-term basis to deliver optimum benefits. 3) Mow Any Horsetail In Your Lawn If you see horsetail coming through your lawn and you haven’t yet arranged a method to remove it completely, you can prevent it from growing too large by mowing regularly. This is definitely a measure designed to control, rather than remove horsetail, though. 4) Digging Up As Much As Possible While you’ll never remove an entire plant once it’s fully established, you can weaken growth by repeatedly digging up as much as you can reach. The damaged underground roots will most likely sprout again and pop back up, making this something like a game of whack-a-mole, but you may be able to curtail the worst of the growth. “Removing shoots, mulching, mowing and digging up are all methods that will reduce horsetail over time,” shares Colin Skelly, a Master Horticulturist. “In my experience, turning over a horsetail-infested area to grass and mowing provides the best control as it regularly removes the foliage, weakening the plant to the point of elimination over time.” 5) Consider The Use Of Weed Killer Horsetail will respond to treatment with weed killer, but the deep rhizomes may cause problems still more. Unlike some weeds which can be eradicated in one year through the correct application of weed killer, horsetail may require a prolonged campaign spanning several years. Each successive treatment is likely to further weaken the rhizome network, with the cumulative damage hopefully offsetting any recovery the plant is able to achieve between treatments. Here are some things to bear in mind when using weed killers to control horsetail – Bruise the roots of the plant first to weaken the membrane and encourage higher absorption of weed killer. This will help the weed killer to reach more of the plant, and to cause more damage. Try to use a weed killer that won’t damage surrounding grasses. This will encourage grass to spread into the area recently vacated by horsetail, increasing the amount of competition and reducing its ability to re-establish itself. Horsetail FAQs With such a fearsome reputation, there are a lot of questions and a lot of misinformation around horsetail. In this section we’ll address a couple of these questions, to make sure you’re working with the very best information. Can Vinegar Kill Horsetail? No, vinegar cannot kill horsetail. This is quite possibly an old wives tale, but sadly it’s not one of the ones that holds truth. Horsetail is so vast and sprawling that the mild acidity of vinegar is nowhere near enough to cause the level of damage required to kill the plant. Can You Dig Up An Entire Horsetail? While it’s theoretically possible to dig up horsetail, the amount of work required almost certainly renders this option unsuitable. The rhizomes of the plant spread out far and wide underground, up to depths of around two metres, meaning that you’d have to dig up an enormous amount of soil to get anywhere close. And that’s not taking into account outward growth – potentially reaching into other gardens, under structures, and so on. Unless you’re planning to excavate your entire garden and start again from scratch, we really don’t recommend considering this option. Should You Trim Horsetail? Although trimming horsetail back won’t do anything about the underground part of the problem, the technique can be used to keep the plant in check. Horsetail grows fairly quickly so you may find yourself doing this quite often, but it’s a good way to protect against unruly horsetail above the ground. References 1. Nice, G., & Sikkema, P. (2007, May 24). The Ancient Horsetail. Purdue University. Retrieved March 17, 2023, from https://www.extension.purdue.edu/extmedia/ws/ws-29-w.pdf 2. Distribution and biology of horsetail in the UK. (n.d.). AHDB. Retrieved March 17, 2023, from https://ahdb.org.uk/knowledge-library/distribution-and-biology-of-horsetail-in-the-uk 3. Burrill, L., & Parker, R. (1994, July). Field Horsetail and Related Species. Maine: Gov. Retrieved March 17, 2023, from https://www.maine.gov/dacf/php/gotpests/weeds/factsheets/horsetail-nw.pdf 4. Report a Horsetail weed problem. (n.d.). Preston City Council. Retrieved March 17, 2023, from https://www.preston.gov.uk/article/2250/Report-a-Horsetail-weed-problem
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Struggling With Potato Blight? Reduce The Chances Of It Taking Hold With These Steps
IN THIS GUIDE What Is Potato Blight? What Causes It? Identifying Potato Blight Reducing Blight Taking Hold Treating Potato Blight Cutting Your Losses References Potato blight is an annoying problem and one that many UK gardeners will experience at one time or another. Unfortunately, potato blight is a serious issue. It can cause significant reductions in yields and may, in extreme cases, mean that you lose your potato crop altogether. That said, it is important to recognise that, while it is nigh on impossible to get rid of, it is possible to identify and deal with it quickly, and to take steps to reduce the chances of potato blight taking hold. What Is Potato Blight? Potato blight is a fungal infection that can attack potato plants and other members of the same plant family, such as tomatoes.1 It is also referred to as ‘late blight’ to distinguish it from ‘early blight’ which is common in the US and elsewhere, but uncommon in the UK.2 If symptoms resembling those of blight occur earlier in the year in the UK, it is usually a case of magnesium deficiency instead.3 Throughout history, late blight has been responsible for a number of catastrophic crop losses. It was implicated in the famines in Europe in the 1840s, in 1845 in Ireland, and the following year in the Highlands of Scotland.4 An over-reliance on the potato crop meant that populations were left vulnerable, and many died when late blight destroyed the majority of the harvest. Fortunately, most gardeners and growers today don’t have all their eggs in one basket. Though blight is a common problem, it rarely destroys whole harvests. And even when the potato harvest does suffer, home growers usually have a range of other crops that may well have fared better in a bad year for potatoes. What Causes It? Potato blight is caused by a microorganism – a fungus called Phytophthora infestans.5 The spores can linger for years in the soil, and since they thrive in damp and soggy conditions, they will tend to be more prevalent when there has been a wet summer.6 When the fungus reaches the plants, it will infect them and spread – often very quickly – through the plant tissue. Identifying Potato Blight Tubers affected with late blight. Potato blight is usually first noticed as brown areas that appear on the foliage of potato (or tomato) plants. These brown areas will speedily spread into a wet rot that kills the leaves, spreading to the stems and turning them brown too. If nothing is done, the infection can spread from the leaves and stems to the potato tubers. If they become affected, potato tubers will have a reddish-brown discolouration below the skin and will become rotten and soft. Tuber blight may not be immediately obvious when the crop is harvested, but the tubers that have been affected will rot quite quickly in storage. Reducing Blight Taking Hold If blight is present in your area, then unfortunately there is not much you can do to entirely eliminate the risk that it will take hold in your potato crop. However, there are certain things that you can do to reduce the risk that it will become a major problem: 1) Grow Early Harvest Potatoes Firstly, you can consider growing only potatoes that will be harvested before it is likely that blight will become a problem. First early potatoes are harvested around July, and so will be out of the ground before the blight arrives in late summer. “My approach to avoiding potato blight is to grow first earlies, harvesting from late June to mid-July,” shares Colin Skelly, a Master Horticulturist. “Living in a mild, moist part of the UK, blight is unavoidable and resistant varieties only after a slight delay on the inevitable. First earlies are still wort growing and offer a great range of tasty and productive cultivars.” 2) Consider Blight Resistant Varieties ‘King Edwards’ It is worthwhile noting that even ‘blight resistant’ varieties of potatoes are not invincible. But you can significantly reduce the chances of severe infection if you choose those with the highest blight resistance levels. In the UK, some options are: ‘Athlete’ ‘Cara’ ‘Carolus’ ‘Orla’ ‘Sarpo Mira’ ‘Valor’ Some common and favourite varieties are particularly susceptible, and so it may be best to avoid these in areas where blight is a particularly pressing problem. These include: ‘Arran Pilot’ ‘King Edwards’ ‘Majestic’ ‘Sharpe’s Express’ 3) Take Care When Watering Water early in the morning if possible, so leaves have a chance to dry out before nightfall. And try to make sure you water plants at the base – delivering water to the roots where it is needed and avoiding getting the foliage wet. Wet leaves will make it more likely for blight to appear. 4) Ensure Good Ventilation Make sure you do not place your potato plants too close together and are not overcrowded. Good ventilation can help to reduce the incidence of fungal disease and keep plants as healthy and resilient as possible. 5) Earthing Up & Mulching Earthing up or mulching around your potato plants won’t keep blight away. But it might offer some level of protection to the edible underground portions of the plant, and ensure that even when the plants above the soil are affected, you still get an edible yield. 6) Implement Crop Rotation Finally, you can reduce the chances of a serious blight problem by making sure that you don’t grow potatoes (or other members of the same plant family) in the same location year after year. Ideally, you should have a four-year crop rotation plan in place for your annual growing areas. Treating Potato Blight It is important to check growing and stored potatoes regularly for signs that blight has taken hold. The quicker you can catch the problem, the less likely it is to spread widely to affect other plants, and the less likely it is that the blight will spread to affect the tubers as well as the above-ground portion of the potato plants. Early signs of blight To be forewarned about blight in your area, you can register for Blightwatch in the UK, which sends out alerts at postcode level.7 If you see signs of blight, quickly remove the affected plant material and burn it, or dispose of it well away from your garden and composting areas. Reducing The Spread Make sure you practice good hygiene – wash your hands and any tools, avoid touching other plants and spreading the disease. To reduce the chances of infection of plants currently unaffected, you can consider using anti-fungal organic treatments on the foliage of your plants. For example, you can spray 10g of bicarbonate of soda in 1 litre of water onto the tops and undersides of all the leaves. Do so early in the morning to avoid leaf scald. However, this and other anti-fungal treatments are only ever partially effective. You can also reduce the chances of late blight from setting in by using an activated hydrogen peroxide fungicide or a fungicide containing Streptomyces lydicus – a beneficial bacteria. However, if a bad fungal infection has already set in, then it may well be too late to do much. These solutions generally just help to avoid a problem from spreading further. Be sure to only ever spray an organic fungicide, and only ever as a last resort. Cutting Your Losses Depending on when exactly blight takes hold in your potato crop, it can be a good idea to cut your losses and remove all above-ground portions of your plants. Of course, this means that the tubers will not grow anymore, but it should mean that you are able to harvest the tubers. If 25% of the leaves on potato plants are affected, you should certainly cut off all the stalks near ground level. Be sure to rake up and carefully remove all the debris from the area. After around two weeks, the skins on the tubers will be hard and you can dig them up and eat them or store them for later. References 1. Schumann, G., & D’Arcy, C. (2000). Late blight of potato and tomato. APS. Retrieved March 23, 2023, from https://www.apsnet.org/edcenter/disandpath/oomycete/pdlessons/Pages/LateBlight.aspx 2. Early Blight. (n.d.). Bayer Crop Science UK. Retrieved March 23, 2023, from https://cropscience.bayer.co.uk/threats/diseases/potato-diseases/early-blight-potatoes/ 3. Potato – Magnesium deficiency. (2018). Ephytia. Retrieved March 23, 2023, from https://ephytia.inra.fr/en/C/21161/Potato-Magnesium-deficiency 4. The Irish Famine: Potato Blight. (n.d.). Ireland Story. Retrieved March 23, 2023, from https://www.wesleyjohnston.com/users/ireland/past/famine/blight.html 5. Potato Late Blight. (2019, July 22). CropWatch. Retrieved March 23, 2023, from https://cropwatch.unl.edu/potato/late_blights_description 6. Farm Advisory Scotland, & Burnett, F. (2017, December 22). Wet summer raises risk of potato storage rots. Farm Advisory Service. Retrieved March 23, 2023, from https://www.fas.scot/news/wet-summer-raises-risk-potato-storage-rots/ 7. Home. (n.d.). Blightwatch. Retrieved March 23, 2023, from https://blightwatch.co.uk/
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