Growing
Grow Borage As A Fantastic Border Plant For Pollinators - Experts Share How
IN THIS GUIDE Overview Common Borage Varieties How To Grow Borage Soil Requirements Sowing Plant Care Watering & Feeding Deadheading Composting Harvesting Common Problems References As an attractive border plant, enticer of pollinators and herb for salads and drinks, borage is a versatile and vibrant addition to any garden. Also known as bugloss or starflower, borage is a hardy herb that’s easy to grow, great for encouraging biodiversity and attractive for its colourful blossoms. Most varieties are annuals, meaning they’ll complete their entire life cycle within a single season, but there is a perennial version of borage that also yields good results in a backyard display. It’s a huge favourite among the bees and butterflies, making it a great choice to plant in among other herbs, fruits and veggies since it will enhance the chances of pollination. “Borage is so popular with pollinators because it produces so many flowers that are resource-rich,” according to RHS Master of Horticulture Colin Skelly. “These flowers supply large amounts of nectar that is re-filled rapidly when consumed and is accessible to lots of pollinators. “You can always hear a good pollinator plant because of the hum of feeding pollinators – listen next time you’re in the garden and find out which plants in your garden pollinators are making a bee-line for!” Although Borage is not as famous or as commonplace as other herbs like basil, mint and thyme, borage is a superb culinary condiment in its own right. Overview Botanical Name Borago officinalis Common Name(s) Borage; Starflower Plant Type Annual Native Area Mediterranean Hardiness Rating H3 Foliage Hairy leaves with long stems Flowers Blue, star-shaped flowers When To Sow March, April Plant Out May, June Harvesting Months June, July, August, September, October All parts of the plant (excluding the roots) can be harvested and eaten, imparting a cool and refreshing flavour to food and drinks that are reminiscent of cucumber.1 Its blooms are most commonly used to garnish drinks or infuse teas, while its leaves can add zip and zing to salads, sandwiches, dressings and side dishes. With so many attractive attributes, then, it’s little wonder that borage has quite an illustrious history. Are you won over yet? Follow these simple tips to encourage plentiful borage in your own garden. Common Borage Varieties Most borage varieties are annual, which means that they will die out within a single year, though many are very adept at self-seeding. On the other hand, there are some cultivars that are perennial. Although the flowering season of these is generally shorter, they do last for several years or more. Here are four of the most common varieties to choose from: B. officinalis The most widely available borage variety, Borago officinalis is also the most popular among UK gardens. It’s an annual capable of growing up to 60cm in size and boasts star-shaped flowers of a brilliant blue in summer. B. officinalis ‘Variegata’ An offshoot of the common borage variety named above, this grows to a similar height and also has blue flowers, though these are of a softer hue. Its distinctive feature is the white mottling on its leaves. B. officinalis ‘Alba’ Sometimes known as white borage, this is a slightly sturdier specimen than the two mentioned above which blooms later in the year. Its biggest difference, however, is the whiteness of its blossoms. B. pygmae The Latin name of this perennial strain of borage indicates that it’s smaller than its annual brethren, growing to around half (30cm) their size. It has a creeping habit and enjoys a short life, but will come back again every year. Deciding which type of borage you prefer in your borders and backyard displays will depend primarily upon whether you’re looking for a perennial or an annual, what size plant you wish for the space available to you and whether you’d prefer blue or white blooms. How To Grow Borage It does insist upon exposure to the sun, however, so make sure you plant it in a spot that receives sunlight for at least half of the day. Soil Requirements Thankfully, borage is an unfussy plant that will grow in most soil types with little in the way of fertilisation or maintenance. The plant absolutely hates waterlogged soil, so if your garden is particularly slow draining, you may wish to prepare the area with fine-grit or gravel. It prefers soil that isn’t particularly fertile, so there’s usually no need to add any artificial additives to its planting environment. Mulching with organic matter is not strictly necessary, but will certainly encourage a fuller and larger plant. Sowing Ideally, you should seed borage exactly where you wish it to flower, since it doesn’t take too kindly to transplantation. It can handle a potted environment if that’s preferable, though you should ensure that you select a pot large enough for its roots to grow and spread – that means at least 30cm in diameter and 25cm in depth. The best time to sow annual borage seeds is in mid-spring (April/May), though a second sowing is possible later in the season. Perennial borage seeds will also perform best when planted at this time, but are more forgiving if put into the ground at any other time of the year. The plant is quite effective at self-seeding, so if that’s something you wish to encourage, simply leave the faded flowers on the plant. If not, remove them as soon as they have finished blooming and collect the seeds for replanting the next year. To plant, simply dig out a little hole 1.5cm deep and place a single seed in it, then cover over with moist soil. Space out your rows 30cm apart and once the seedlings have begun to break through and reach a height of around 5cm, thin them out to ensure there is at least 30cm between them. If they grow any closer together, their foliage can begin to develop symptoms of mildew, as air movement will be restricted. Plant Care As alluded above, borage is invariably a hardy and stress-free plant to grow – it’s even been known to thrive in rubbish dumps and at the sides of roads and highways! Watering & Feeding Borage is from the Mediterannean, so it copes with low rainfall but might need to be topped up with your own water in times of drought or dryness. If growing indoors in a container, it will require frequent irrigation, which could even mean daily watering during summer. The same goes for its feeding habits – fertilisers do not need to be used unless you’re growing it in a pot using store-bought compost. Deadheading As for maintenance, annuals do not require any pruning whatsoever. Perennial varieties may demand occasional paring back during the peak of the warmer months. Having said that, both will benefit from stripping away faded flowerheads to encourage further growth of more flowers during summer, though it’s not strictly necessary. Deadheading will prevent the plant going to seed so make sure this is something that you wish to prevent. Composting Once the flowering season of an annual has run its course, simply dig up the whole plant by its roots and use it as compost for the following season, as the nutrient-rich leaves will enhance fertilisation of the soil next time around. If you are going to use the plant as compost, be sure to remove its seed heads first, however, or you could soon find borage popping up all over the garden! Harvesting The leaves and the flowers are the parts of the plant most commonly harvested for culinary purposes, both of which should be plucked in the morning after the dew has dried, but before the sun has reached its full strength and made either wilt. The leaves lend themselves well to spicing up salads and dressings with a refreshingly cucumber-like zing. Alternatively, you can sauté or blanch them as you would with other leafy greens like kale and spinach. If you wish to use them as dried seasoning, simply hang them in an airy room for a day or two, or else pop them in the oven for 10 minutes. Dried leaves also work well as a salt substitute. They work especially well when frozen into ice cubes, which is a great way to conserve them if you have too many. Common Problems In general, borage is a resilient grower that won’t succumb to many pests or blights. However, there are a handful of potential issues you should be aware of, including: Mildew As mentioned above, mildew is a debilitating consequence of planting borage plants too close together. Thankfully, it’s normally solved with ease – simply space the seedlings at least 30cm apart to allow plentiful airflow beneath. Watering it at the base of the stem rather than onto the leaves can also help. Blackfly Otherwise known as black bean aphids and bean leaf aphids, blackflies have been known to have their heads turned by borage foliage, too. In itself, this isn’t strictly a problem and shouldn’t endanger the survival of the plant; in fact, it can actually be a boon by distracting the pest from bean crops. Woolly Bear Caterpillar These tiny creepy-crawlies are about as furry as they are unfussy and they’ll happily feast on any low-lying foliage they come across. In practical terms, that means that encountering them on borage plants means they’ll likely be gobbling up other produce too, so control them with neem oil. Painted Lady Butterfly This pest causes more mild frustration than all-out desperation, usually concentrating its attacks on a single part of the plant rather than the whole thing. Its larvae do more damage than the actual butterfly, though neither are too severe. Deter it with sticky traps or natural insecticides. Flea Beetle Flea beetles come in a variety of different kinds, all of which love to gnaw through the leaves of borage plants. Though they don’t do too much damage beyond the cosmetic in moderation, if you get an infestation, it can lead to more serious problems. Clean up fallen leaves and other debris to remove their habitat in late autumn. References 1. Borage recipes. (n.d.). BBC Food. Retrieved March 28, 2023, from https://www.bbc.co.uk/food/borage
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Cineraria: Clearing Up Some Confusion When Growing Either Plant Type
IN THIS GUIDE Overview Dusty Miller Pericallis x hybrida Cineraria Types How To Grow Cineraria Growing From Seed Planting Out Cineraria Plant Care Common Problems Cineraria are popular florists’ plants, but there is some confusion over the name. Cineraria is a term often applied broadly to plants in the Senecio genus or other related genera. It is also a name used to refer to Pericallis x hybrida, sometimes called ‘Florist’s cineraria’, a group of hybrids bred from Canary island species now technically referred to as Pericallis. Strictly speaking, the genus Cineraria is now restricted to a smaller group of South African plant species. Many of the plants commonly referred to as Cineraria are not actually recognised by botanists as Cineraria anymore. Pericallis x hybrida “It can be quite tricky to keep up with the changes to botanical names,” explains Horticultural Consultant Colin Skelly. “I use the Royal Horticultural Society and Kew websites as reputable resources for the correct names. “Often the older names will persist amongst gardeners and nurseries, as with Cineraria, but it is good to try and keep up as classification becomes more accurate and is based on DNA rather than just the physical characteristics.” Nonetheless, there are two main types of plant referred to as Cineraria which are grown in UK gardens; these are the types that we will concentrate on in this article. The first type is Jacobaea maritima (dusty miller), and the second type is Pericallis cruenta x P. lanata, AKA P. x hybrida – these are greenhouse or annual bedding plant varieties commonly called simply ‘Cineraria’. Overview Botanical Name Jacobaea maritima / Pericallis x hybrida Common Name(s) Dusty Miller, Florist’s Cineraria Plant Type Annual / Houseplant Native Area Italy / or Hybridized garden forms Hardiness Rating H3-H4 Foliage Evergreen or deciduous Flowers Various When To Sow March, April, May Plant Out June, July Harvesting Months June, July, August In this article, we will introduce both Senecio cineraria and P. x hybrida, since both of these plants are commonly grown as pot plants or, less commonly, as border plants in the UK. Dusty Miller Jacobaea maritima, ‘dusty miller’ or ‘silver ragwort’, is a subshrub typically grown as an annual in UK gardens. Although correctly known as Jacobaea maritima, it is still widely referred to as as Senecio cineraria. It has striking, silver-white leaves that look like they have been dusted with frost, which means that they stand out well against green shades of foliage, and help to add interest to pots, planters, beds or borders. It is H4 hardy which means that it is hardy throughout much of the UK, and may well overwinter outdoors in a sunny, sheltered spot. Though usually grown for their foliage rather than their flowers, these plants sometimes also have yellow, daisy-like flowers in summer. Pericallis x hybrida P. x hybrida are evergreen perennials which are also often grown as annuals in the UK. They form low clumps of dark green foliage, and bear loose groups of bright coloured blooms over the summer months. They are often H3 hardy and may overwinter successfully in a greenhouse, or in the mildest parts of the UK. Their large daisy-like flowers can be very attractive in beds, borders or containers over the summer months, and come in many shades from blue, to purple, to pink, to red, to white – often with dark centres which can be in a different colour. Often, these flowering plants are grown as temporary annual houseplants indoors or under cover. Cineraria Types When it comes to Cineraria, which type you will choose to grow will largely depend on where you plan to grow them. Indoors, you will usually be looking at Pericallis ssp. In your garden, these may still be an option, but less tender Senecio will perhaps be easier to grow outdoors. If you are looking for a Silver Ragwort to grow, try ‘Silver Dust’ which has received the RHS Award of Garden Merit. ‘Silver Dust’ If you are looking at Florist’s cineraria, then the Senetti Series offers many of the most common choices. Some interesting named varieties are: ‘Jester Scarlet’ ‘Magic Salmon’ ‘Sunsenedibu’ ‘Sunsenere’ ‘Sunsenereba’ How To Grow Cineraria Jacobaea maritima will grow well in any well-drained soil in sunny position, in pots or in the ground. It works well for beds, planters or containers which face south or west, and can cope with drought and windy conditions, as well as a more sheltered spot. P. x hybrida cineraria does best in full sun or partial shade; its tolerance to shade is one of the reasons which is why it can work well as a houseplant for the summer, as well as being grown outdoors as a pot plant or summer bedding plant. ‘Senetti Magenta Bicolour’ It can thrive in any fertile, well-drained soil – though if you plan to overwinter your plants, they must be kept in a dry, cool, frost-free spot. Growing From Seed S. cineraria or Jacobaea maritima seeds should be sown in spring, between March and May at 19-24°C for optimal germination rates. You can also take semi-ripe cuttings of these plants in the mid-late summer, or purchase plants from your local garden centre or plant nursery if you prefer. Plant out in beds or containers in May or June. In milder areas, it may overwinter outside as mentioned, but you may prefer to grow it as an annual, or grow it in containers which can be moved indoors in autumn when frost threatens. P. x hybrida cineraria seeds are sometimes sown in December, but when grown indoors, the seeds can be sown any time throughout the year. The seeds are very small and are pressed into the surface of the potting mix or growing medium. They are best sown in a propagator, and provided with temperatures of 18-20°C. Shoots appear around two weeks after sowing, and seedlings are then potted up and should be kept at around 15°C for best results. These plants can also be propagated by means of semi-ripe cuttings in mid-late summer. Planting Out You can also, of course, take the easy option and purchase bedding plants. Whether you sow or propagate your own plants, or buy your Cineraria, again, you should plant them out in May or June. Treat them as annuals or overwinter them as above in a dry and frost-free place as mentioned above. However, it is worth noting that these Cineraria rarely bloom more than once, and so they do not make great perennials in most UK gardens and are best treated as annuals. Cineraria Plant Care J. maritima is a fairly easy plant to grow in containers or in your garden and it is an ornamental plant that we’d definitely recommend. In order to encourage the plants to put on plenty of new foliage growth, it is generally best to cut back any long shoots to suppress flowering – since the foliage is the main decorative feature you are after. Florist’s cineraria are beautiful flowering plants, no doubt, but they are short-lived and will take a lot more work. If bought as bedding plants, it is worth noting that this can be an expensive option – and not the most sustainable choice. These flowers can be finicky – requiring just the right light levels, amount of water, humidity etc. and only providing blooms in summer (or other seasons when grown indoors) for a relatively short length of time. Common Problems Cineraria can also be plagued by a range of pests and problems: Cineraria are beloved by aphids, thrips and whiteflies. Spider mites are also a common issue. Fungal issues such as mildews, root rot and common rust can also commonly occur. In your garden, be sure to maintain a balance in the garden ecosystem with as much biodiversity as possible. Use companion plants and attract beneficial predators to help you keep pest numbers down – for example, marigolds can work well as shown above. For home growers, there are better choices perhaps, than these fussy flowers, but many still love to grow them for their beautiful blooms.
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Grow Radish For An Easy Harvest: 'I Always Recommend Them To First-Time Growers'
IN THIS GUIDE Overview Habitat & Growing Conditions How To Grow Radishes Harvesting Common Problems References A crispy, mildly zesty component of summer salads in Europe, and a richly-flavoured culinary ingredient in spicy cooked dishes in East Asia, the Garden Radish is a wonderfully versatile root vegetable, thanks to its very varied cultivars. Apart from being a popular veggie, the Garden Radish is much appreciated by gardeners of all stripes – growing it is quite literally child’s play! “I always recommend radishes to first-time growers,” shares Garden Writer Kathy Slack. “Except in the hottest summers when they can bolt, they are the easiest, quickest and most joyful of veg to grow. “They’re very easy and quick to offer results; just sow, water and wait and in 6 weeks you’ll have a clutch of ruby jewels.” The radish is one of the few truly global vegetables, for it is consumed the world over. Overview Botanical Name Raphanus sativus Common Name(s) Radish Plant Type Annual Vegetable Native Area Cultivated Hardiness Rating H3-H4 Foliage Lobed leaves with basal rosette Flowers Small four-petalled white flowers When To Sow / Plant Out February, March, April, May, June, July, August Harvesting Months January, February, June, July, August, September, October, November, December A root vegetable like the potato, it belongs to the Brassica Family or Mustard Family which accounts for its piquant taste.1 This root’s amazing variety also adds to its versatility: a few cultivars are mild, even sweetish; at the other extreme, a few are pungent. Many cultivars are flavourful with a pleasingly sharp taste. These various radish cultivars’ origins are debated. They are widely thought to be cultivated from what used to be a single sub-species: Raphanus raphanistrum subsp. sativus. While this would mean the commonly-cultivated, edible radish was technically a sub-species of R. raphanistrum, the Wild Radish, it is now usually identified by its synonym R. sativus; this elevates the plant to the level of a species on its own. It has been so altered by millennia of human cultivation that, disconnected from any confirmed wild ancestor, it is technically a cultigen, defined by the Oxford English Dictionary as “a plant species or variety known only in cultivation, especially one with no known wild ancestor”.2 The thick, fleshy taproot of the plant is the vegetable we know and love (or not!) as the radish. Most frequently light red on the surface and white inside, varieties can be white, orangeish, beige, brown, purple, and even black. However, the flesh is almost always white. Habitat & Growing Conditions R. sativus or the Garden Radish has escaped from cultivation in some regions of the United States where it is found, albeit infrequently, in disturbed soils, close to vegetable gardens, near rubbish dumps, and alongside highways. It takes root in uncultivated but fertile and moist ground in areas with higher-than-average rainfall and with full sun. In the wild it puts up four-petalled purplish-white flowers that attract bees and other pollinators. It spreads, though very gradually, by seed. How To Grow Radishes Sowing The sowing and harvesting season are very long, and sowing and harvesting seasons also overlap; thus, radishes can be sown, grown, and/or harvested literally year-round. Sowing season runs from February (under protection) or March through September and harvesting season from May through the beginning of January. As such, radishes can be both sown and harvested from May through August. What’s more, most summer radish varieties are ready for harvest about four weeks from sowing. “To sow summer radishes, I draw a drill about 1cm deep with a draw hoe or cane and label it,” shares Peter Lickorish, a Horticultural Consultant. “I find that by sowing radishes fairly thinly in this drill, I can harvest them at intervals along the line as they gradually develop. “This thins them and at first, yields leaves, then baby roots, before finishing with the last, well-developed radishes no more than six weeks after sowing.” Winter radishes take much longer to mature, typically about eight weeks – though some winter varieties may take ten to twelve weeks. The ‘winter’ part of their name refers to their harvest time. As a rough guide, sow summer radishes from March through early August, and winter radishes from mid-July to September. Check the instructions on each seed packet for optimal sowing time. The trick to enjoying a continuous months-long harvest is to sow seeds in small quantities on a regular schedule during the sowing season. This is known as succession sowing. Soil Requirements Most types of soil will do but a balanced mix of clay, sand, and chalk amended with well-rotted manure or organic compost is a very good type of soil for this root vegetable. The subsoil and underlying ground must be free of stones and rocks. It is a good idea to till the bed to prep and loosen the soil – it must drain very well and not be prone to waterlogging. ‘French Breakfast’ Soil pH ideally should be in the slightly acidic to neutral range, that is 6.1-7.3, but here too radishes give you a fair amount of leeway. Sunlight Summer radishes should get morning sun and indirect sunlight or shade in the afternoon, especially in the sunnier parts of the country. Winter radishes may be grown in full sun locations. Container Growing Besides outdoor beds, summer radishes and the not-so-big winter radishes may even be grown in planters or large containers. Some summer radishes can even be grown in grow-bags. Watering Water well and regularly, say twice or thrice a week, such that the subsoil stays moist. Keeping the soil moist is of special importance when growing summer radishes in full sun. Soil moisture is also a factor when growing winter radishes. If the soil dries out and remains dry for some days, the radishes’ growth will be stunted and they may well end up bland and tasteless, lacking their distinctive rich, flavourful appeal. Irregular moisture levels may cause root splitting or bolting. Harvesting When harvesting summer radishes, the general guideline is that it is better a little too early than a little too late. If you harvest summer radishes a little too early you lose nothing except a bit of size. Pick them a little too late, and the vegetable can quickly become stringy or woody, depending on the variety, with the taste becoming flat, bitter, or unpleasantly pungent. ‘Chinese Radish’ To use size as a general guideline, it is at about 2-3cm in width that summer radishes are young and are best harvested. While summer radishes must be harvested on time, winter radishes allow more flexibility though do not leave them in the ground too long either. Pick winter radishes by eyeballing the width – when a given vegetable looks like it is more or less the correct width for that variety, it can be pulled up. Harvest them early for slicing raw into salads, and late for making pickles, gazpachos, stewing, or for culinary use. Keep in mind that not all types of winter radishes can be enjoyed raw. If the atmospheric temperature is predicted to stay at -5°C or less, you should pull up any remaining winter radishes otherwise they could sustain frost damage. This should not be a worry virtually anywhere in the UK except parts of Scotland. To pick a (small) summer radish, grasp the leaves at the top, wiggle the radish loose, and gently pull it up. It may not work out quite that way with (larger) winter radishes – the elongated or cylindrical types are much longer and much heavier. You can end up with only foliage or a split or broken radish in your hand! If you do not feel the radish getting loose and coming up through the soil, lightly dig around it and remove and loosen the soil until the radish is ‘unstuck’ enough to pull up. A hand fork is ideal for this. Summer radishes should be enjoyed soon after they are harvested, when they are fresh and succulent. Winter radishes may be stored as they will keep well in the fridge’s crisper or even in a bin in a cool basement. The leaves of winter radishes are not only edible, they have their own taste merits. They do not keep well and should be consumed fresh, within 24 hours of picking. Common Problems The flea beetle is perhaps the most common pest to attack radishes. Flea beetles chew up the leaves, especially of young plants, weakening and stunting the growing root vegetable. They often leave round holes in the middle of leaves. Organic solutions may be used to kill these pests and the plants can be protected with narrow-gauge wire netting. Brassica downy mildew is a disease that radishes are prone to – it is a serious disease that destroys the root vegetable, especially at the seedling stage in spring. It is identified by an unsightly white growth covering the foliage, and yellowing of the foliage. Promptly remove and destroy all affected plants – retail controls to treat downy mildews are not available. Slugs and snails eat radish seedlings, but these common garden nuisances are more easily dealt with. References 1. Raphanus raphanistrum subsp. sativus. (n.d.). Global Biodiversity Information Facility. Retrieved March 23, 2023, from https://www.gbif.org/species/144096278 2. Cultigen. (n.d.). Academic Dictionaries and Encyclopedias. Retrieved July 31, 2023, from https://en-academic.com/dic.nsf/enwiki/2764426
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How To Grow Leeks With Elizabeth Waddington - A Reliable, Low-Maintenance Crop
IN THIS GUIDE Overview Common Varieties How To Grow Leeks Leek Plant Care References Leeks are a common and popular winter vegetable, so you might like to learn how to grow them in your garden. They are not always the easiest vegetable to grow, and take a lot of time to mature to harvest – but in spite of the investment they require in terms of time, space and effort, they can still be an excellent choice for home growers. Overview Botanical Name Allium porrum / Allium ampeloprasum Common Name(s) Leeks Plant Type Annual Vegetable Native Area Cultivated Hardiness Rating H4 Foliage Spiky leaves, above-ground Flowers Spherical, elegant blooms – commonly white or purple Harvesting Months January, February, August, September, October, November, December Leeks are a common garden vegetable which is a member of the Allium family. Leeks are, of course, a vegetable with a pleasant, mild, onion-like taste. Most commonly, the white and pale green portions are eaten. But it is important to remember that the darker green leaves at the top are edible too, and these should also be consumed to avoid waste.1 Though tough, they can be good to sauté or add to a stock. Aside from the flavour, another good thing about leeks is that they are a vegetable that is harvested in the autumn or winter, when there are fewer fresh vegetables around. ” I love growing leeks, growing different varieties for harvesting between late autumn and early spring,” shares Master Horticulturist Colin Skelly. “My favourite is the heritage cultivar ‘Giant Musselburgh’, which tastes great and stands even in mild winters without bolting. “Fantastic in winter soups and far tastier when home-grown. this variety is available in supermarkets.” This means growing leeks can help you in your efforts to eat food grown in your garden all year round. Leeks are not only useful for their edible yield – leeks can also be very useful, like other alliums, as companion plants in your garden. Their strong smell is said to help in repelling or confusing a range of common garden pests – though it must be said that some recent studies have proved inconclusive.2 Common Varieties Some good leek varieties for the UK include: ‘Autumn Giant Porvite’ ‘Blauwgroene Winter’ ‘Bleu de Solaise’ ‘Cairngorm’ ‘Krypton’ ‘Mézières’ ‘Monstrueux de Carentan’ ‘Oarsman’ ‘Porbella’ ‘Stamford’ However, as well as considering common F1 or heritage leek varieties are commonly grown in an annual vegetable plot, you could also consider growing perennial leeks, like Babington’s Leek (Allium ampeloprasum var. babingtonii). Babington’s Leek This is a perennial leek which is found in the wild in the British Isles. It is a relative of the garden leek which is believed to have predated the introduction of the garden leek. Typically, bulbs are planted in spring and then left for the first year – the plant is then harvested for its above-ground growth each subsequent year. The bulb in the ground is left intact and the plant will regrow from the bulb. Plants left unharvested will flower, produce bulbils, and drop these to create new plants; clumps of these can form in the right conditions. How To Grow Leeks Leeks are usually grown in the ground in a garden, but they can also do well in deep raised beds or large, deep containers. Both typical garden leeks and perennial leeks will do best in full sun but can also be grown in partial shade. The ground into which garden leeks are planted should be fertile, and rich in organic matter, while the soil should be moist but relatively free-draining. Crop Rotation You should also consider, when planning your companion planting schemes, that crop rotation is still the best idea. Try to include alliums like leeks within a four-year crop rotation plan. Perennial leeks work very well as companions for strawberries, and other perennial vegetables – again for their strong scent which can confuse or repel a range of pests. Fruit trees like apple trees will also benefit from having perennial leeks and other perennial alliums planted in their guilds, since the perennial alliums help in repelling pests and may also help prevent apple scab and other fungal issues. Sowing Leeks Leeks are a vegetable that takes a long time to mature. If you want to enjoy eating leeks from your garden in winter, then you need to sow the seeds in late winter or early spring. Leeks are usually sown in the UK between February (indoors) and April. See our sowing guide for more information. Leek Plant Care Caring for leeks is relatively easy and straightforward. Simply water during dry periods, and add more mulch over time, or earth up, to encourage the stems to form longer white sections. Make sure that the mulch remains in place over the summer, and remove any weeds which appear between the plants, since leeks will not be very tolerant of any competition. There are however certain problems commonly encountered by those growing leeks in their gardens. Leek Rust One common issue is leek rust, a fungal infection. Making sure that the leeks are not overcrowded and avoid watering from above to reduce the chances that fungal problems like this will take hold. A small rust attack will not kill your leeks, but a more serious attack could reduce your yield. This disease is difficult to eradicate from the soil once it arrives, so practice crop rotation and avoid growing any members of the allium family in the same bed for the next three years. Onion White Rot Crop rotation and good garden hygiene is also crucial in areas where onion white rot is a problem. This is another fungal infection which can attack leeks. Take care not to spread soil or plant material from areas that have this soil-borne fungus to other parts of your garden or elsewhere. References 1. Hunt, T. (2019a, May 11). Go green: don’t let the tastiest part of a leek go to waste. The Guardian. Retrieved March 21, 2023, from https://www.theguardian.com/food/2019/may/11/leek-tops-soup-recipe-food-waste-not-tom-hunt 2. Baudry, X., Doury, G., Couty, A., Fourdrain, Y., Van Havermaet, R., Lateur, M., & Ameline, A. (2021). Antagonist effects of the leek Allium porrum as a companion plant on aphid host plant colonization. Scientific Reports, 11(1). https://doi.org/10.1038/s41598-021-83580-8
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Choose Dwarf, Branching Sunflowers When Growing In Pots - Experts Share Their Tips
IN THIS GUIDE Potted Sunflower Varieties Choosing Pots For Sunflowers Filling Your Containers Sowing Sunflowers In Pots Placing Sunflowers In Containers Caring For Potted Sunflowers Sunflowers are cheerful and useful flowers to grow in your garden, and they can also grow in pots. Planting sunflowers can be a fun activity for the whole family to enjoy. The large seeds are easy for children to handle – and since the sunflowers grow quite quickly, kids and novice gardeners do not have to wait too long to see the results of their efforts. This guide is written for those wishing to grow in garden containers – if you’re planting sunflowers in the ground, check out this care guide for better-suited advice. Potted Sunflower Varieties If you plan to sow and grow sunflowers in pots rather than in the ground, it is best to choose smaller varieties. The tallest and most vigorous sunflowers will do best when grown in the soil in your garden. Fortunately, however, there are plenty of great options to choose from. We would recommend considering dwarf, branching sunflowers, which produce not just one single flower head, but multiple flowers on the same plant. “If you only have space for pots, the traditional ‘grow the tallest sunflower’ challenge can be replaced with a ‘grow the most flowers competition’ for dwarfing cultivars,” says Master Horticulturist Colin Skelly. “This can also introduce watering, feeding and deadheading into the care regime.” These will offer you the best value in your container garden, and be great for bees and other wildlife. Though traditional single-headed sunflowers can also be grown in pots and even tall sunflowers can be grown in containers of sufficient size. Some interesting sunflowers to consider growing in containers include: ‘Little Dorrit’ ‘Pacino Gold’ ‘Dwarf Sunspot’ ‘Waooh’ ‘Sun Tastic’ ‘Little Leo’ ‘Dwarf Yellow Spray’ ‘Big Smile’ ‘Ms Mars’ ‘Teddy Bear’ Choosing Pots For Sunflowers You can start out sunflowers in small containers. There are a range of reclaimed materials that you can use to make this a really cheap and eco-friendly project. You can sow your sunflower seeds in toilet roll tubes, small scrap paper pots, or yoghurt pots, for example. One other fun thing to consider is having kids make their own starter pots for sunflowers from papier-mache (scrap paper/flour glue) or cardboard boxes. Then you can pot up your sunflower seedlings into larger containers; again, a range of reclaimed materials can be considered. The size of container that you will need for your sunflowers will depend on which variety (or varieties) you have chosen. Smaller dwarf sunflowers that grow to around half a metre tall can be grown in a 25-30cm pot. Taller specimens will need a larger container – 5 gallons or even bigger for the most vigorous varieties. So when choosing a container, make sure you understand how large your sunflower will eventually grow. Make sure that many containers you choose allow water to drain freely through the base. Sunflowers do not like to have a saturated growing medium around their roots. Filling Your Containers Once you have chosen your starter pots and longer-term containers, and have the seeds for your sunflowers ready, you should fill the pots with a multi-purpose peat-free potting soil, or a mix of homemade compost. It can also be a good idea to add some crocks (broken pot pieces) or gravel to the bottom to aid with drainage in the larger containers into which your sunflower seedlings will be placed. Sowing Sunflowers In Pots Sunflower seeds are best sown indoors, in April, to give the plants a good head start. Place two seeds into each starter pot, pushing each one around 2cm down into the growing medium, then gently covering them over and watering them in. Keep the growing medium moist and seedlings should emerge within around 7-10 days. When the seedlings emerge, make sure that you water every day. Remove the weaker seedling from each pot by snipping them off at soil level so you do not disturb the roots. Grow on in the starter pot and then transplant into the larger container once they have grown more and are ready to be placed into their final growing positions. If you have used a biodegradable starter pot, you can simply place this within a larger container. This is a good idea because it minimises root disturbance – but it is not essential. Sunflowers are generally very forgiving and you do not need to be too precious. Move your sunflowers in pots outside as soon as all risk of frost has passed in your area. Placing Sunflowers In Containers Sunflowers in pots should be placed in a sunny and sheltered location. They should be out of strong winds, with as much light as possible. Make sure you choose a spot that gets at least 6 hours of sun each day. Often, sunflowers will be grown in their own specific pots, but smaller dwarf sunflowers could also be grown in larger containers or planters alongside other annual flowers. Even when growing in pots, it can also be a good idea to think about the benefits that sunflowers can confer on other plants. They can be a great companion for a number of common crops in a fruit and vegetable garden, for example. Place sunflowers in pots close to fruiting plants like tomatoes to draw in pollinators and other beneficial insects. And note that sunflowers can be useful as a trap crop for aphids and other sapsuckers. Ants may sometimes herd aphids onto sunflower stems and this can keep them away from your main edible crops. Caring For Potted Sunflowers Caring for sunflowers in pots is very easy, but one thing that you do have to remember is that sunflowers are pretty thirsty plants. Watering They will need plenty of water through the summer months. When growing them in pots rather than in the ground, you will need to water more frequently and keeping the growing medium moist will be even more important. Feeding Sunflowers grown in a good quality compost/potting mix may not need additional fertilisation. However, to keep your flowers as healthy as possible and get them to grow to maximum size, you should consider feeding your pot-grown plants with a potassium-rich liquid plant feed. An organic liquid feed like comfrey tea which is suitable for tomatoes will also suit sunflowers very well. Protection Sunflowers can be very appealing to slugs and snails. You may wish to take steps to protect your sunflowers in pots from these pests, especially while they are young and vulnerable seedlings. You might place copper tape around the edge of a pot, for example, or sprinkle crushed eggshells around the base of the plants. But the best way to manage slugs and snails in the garden is to make sure you attract plenty of beneficial wildlife. Attract creatures that eat slugs and snails to your garden and this will help keep their numbers down. Saving Seeds If you are growing a heritage sunflower, you can save the seeds for next year. F1 hybrids will not typically come true from seed (they will be different from the parent plant). However, you can still save the seeds to plant next year and you may see new and interesting variations. After flowering, each flower head will produce abundant seeds. Save some to plant next year and remember, you can also eat some too. This is a useful edible yield from this plant usually grown for ornamental reasons. However, you should also consider leaving some seeds to feed the finches and other seed-eating birds in your garden. Growing sunflowers is an easy and fun thing to do, and if you have not gardened before, growing some sunflowers can be a great place to start.
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Beware Delphiniums Sensitive Root Systems Before Growing In Pots Says Graham Austin
IN THIS GUIDE Best Container Varieties Container Positioning Container Types Growing Medium Sowing and Planting Container Delphinium Care References Delphiniums usually do best when planted in the ground but they can also be grown in suitable containers. One challenge when growing delphiniums in pots is that they have sensitive root systems and very much dislike overcrowding. Another challenge is that these plants can grow rather tall, and so can be vulnerable to falling over, or being toppled by strong winds, as Home Farm Plants owner & delphinium specialist Graham Austin shares: “When grown in containers, it is important to make sure that the pot can drain well, as delphiniums hate sitting wet. “Staking still needs to be done, but you should be careful, as the pots can blow over if placed on a patio or another hard surface”. However, if you make the right decisions, they can look spectacular in a container garden, and some may even be suitable for attractive cut flowers. There are two main types of delphinium grown in UK gardens, and both can potentially be grown in pots or containers: The first type is perennial delphiniums, which flower in early summer and come back year after year. Some are very tall – over 2 metres – but there are also smaller cultivars that work well in pots. The second type is annual delphiniums, also known as larkspur. These are annual crops, and so flower only for a single season. But their flowers will bloom throughout the summer months and since they are smaller, they may be easier to grow in pots. Best Container Varieties If you decide to grow perennial delphiniums, then it is a good idea to opt for the Magic Fountains series. ‘Magic Fountain’ Delphinium These are smaller delphiniums that will grow to an eventual height of 75-90cm tall, and spread to create clumps of 0.1-0.5m. There are a number of different colours within this range that you can choose from. If you decide to grow annual delphinium, or larkspur, you might consider: Delphinium grandiflora Delphinium ajacis These are easy to grow from seed and are a cheap and cheerful way to fill your patio containers, window boxes or even hanging baskets. They tend to be a little tougher and easier to care for than their perennial cousins. “Species like Delphinium grandiflora retain flowers that have not been cultivated to have larger, often double, flowers,” shares Colin Skelly. “They therefore have the dolphin shape that gave the genus its name – from the Greek for Dolphin: delphis.” Container Positioning Both perennial and annual delphinium like a sunny and sheltered position. It is important to think carefully about the best place to position your potted plants so that you can maintain them easily, and also so that they are not damaged by wind. Be sure to think about sunlight and shade, prevailing wind direction and also about the water needs of your plants and how you plan to meet them. Also consider other plants in your garden – as well as man-made structures and how these affect conditions. You might grow delphiniums in their own containers, or in larger containers as part of mixed planting schemes. Even when plant roots do not have the chance to communicate, you should still think about how each container plant you choose works in relation to the other plants, and the wildlife, in your garden. Container Types Containers for delphiniums, especially taller perennial types, should be heavy and stable. Even in a sheltered spot, it is important to make sure that any pots and containers you choose will not tip over with tall plants like delphiniums within them. Remember to choose a pot of sufficient width and depth to accommodate your plant(s) and pot up as necessary until you have your delphiniums in a suitably large container. Delphiniums do like moisture during dry periods, but it is also important to create free-draining conditions in a container. That means choosing a container that has good drainage holes at the base; it may also be beneficial to raise containers up off the ground so water can always drain out freely. Growing Medium As well as requiring a moist but free-draining growing medium, delphiniums are also hungry plants that will require plenty of nutrients. For this reason, it is important to choose a fertile growing medium. Choose John Innes No. 2, or any good quality multi-purpose peat-free compost with added John Innes, or another loam-based mix. Add grit added to improve drainage, and place crocks at the base of the pots. Sowing and Planting Perennial delphiniums are usually purchased as plug plants in spring, or as potted plants in summer ready for planting out. There are also seeds available for sale, but not all cultivars of perennial delphiniums can be propagated from seed. Plant out these types into your containers in spring or early summer to give them the best chance. However, you can plant out at any time as long as you ensure adequate water and the growing medium is not waterlogged or frozen. Replant at the same level as the plants were at in their previous pot, and water in well. Annual delphiniums (like some perennials) can be grown from seed. The seeds can be sown in spring or in autumn for earlier flowering, then potted up in spring and placed into their containers for blooms over the summer months. Container Delphinium Care Plant Support Some varieties will require support. It can be a good idea to insert canes or stakes into the soil in your containers, and to tie in the delphiniums to these supports as they grow. Watering “Watering may be required more often during the growing season for potted delphiniums”, says Graham. Delphiniums will need to be watered during dry periods over the summer months – remember, watering is more crucial, and more frequent, with container-grown plants. Keep the growing medium moist but not damp or soggy. With perennial types, remember to reduce watering as temperatures cool, and over the winter if you are overwintering your plants. Feeding Delphiniums need good fertility. One important step to maintain that fertility is adding a good quality organic mulch to the top of the pots or containers that you choose. When growing in containers, it is also a good idea to add an organic liquid feed regularly over the summer months. Choose one that is rich in phosphorus and potassium and avoid adding too much nitrogen as this can encourage leafy growth at the expense of flowers.1 Deadheading Perennial delphiniums should be cut back after flowering and annual types should be deadheaded to prolong the summer flowering display. Just remember to leave some to set seed if you wish to collect your own seeds for next year. Overwintering Perennial delphiniums in pots should be moved undercover or into the rain shadow of a wall in winter to prevent waterlogging. Delphinium expert Graham also recommends adding a layer of horticultural grit to your container-grown plants in the winter for extra protection from winter cold and wet. Repotting, Propagation & Division Re-pot delphiniums before they become too crowded, and divide perennial delphiniums every 2-5 years. Of course, dividing mature clumps is one way to obtain new plants. You can also take cuttings or raise from seed as mentioned above. Pests and Problems Delphiniums are very attractive to slugs and snails, so be vigilant for these pests. Make sure you protect your potted plants and attract plenty of slug and snail predators to your garden to keep their numbers down. Powdery mildews can also be a common issue. Avoid overcrowding, and under watering, to reduce the chances of issues like this taking hold.2 But delphiniums, when cared for correctly, are usually relatively trouble-free plants. They are often much easier to grow in the ground, but where there is not space, growing them in a container garden can be a good idea. For more detailed growing advice see our delphinium plant care guide. References 1. Doubrava, N. (2022, August 8). Why Plants Fail to Flower or Fruit. Home & Garden Information Center | Clemson University, South Carolina. Retrieved March 15, 2023, from https://hgic.clemson.edu/factsheet/why-plants-fail-to-flower-or-fruit/ 2. Delphinium-Powdery Mildew. (2022, May 17). Pacific Northwest Pest Management Handbooks. Retrieved March 15, 2023, from https://pnwhandbooks.org/plantdisease/host-disease/delphinium-powdery-mildew
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How To Grow Marigolds (Tagetes) - 'Transplant Outdoors When There Is No Danger Of Frost'
IN THIS GUIDE Overview Habitat & Growing Conditions How To Grow Marigolds Care & Growing Guidelines Common Problems Background & Origins References Marigolds are among the most readily-identifiable of flowers the world over – their rounded, densely-packed, flowerheads in sunny hues from light yellow through gold to red stand out in any garden. Marigolds are valued not only in gardens but for religious ceremonies in India.1 Nearer home, these easy-care plants are more appreciated for their wonderfully long flowering seasons. There’s nothing quite like a Marigold – very full and often a little dome-shaped, its multi-petalled double blooms come in warm tones from lemon yellow through gold to near red. The flowers are good-sized at 5-12cm wide and are also remarkably symmetrical and proportional. They have a very long flowering season; some varieties get started in mid-spring and continue into autumn. Those are probably reasons enough that Marigolds are a summer garden staple in so many countries stretching from the Americas through Europe to Australia.2 Another reason is that these herbaceous annuals are easy-grow low-care plants. The Marigolds that most persons in most regions know and are accustomed to are members of the Tagetes genus.3 Overview Botanical Name Tagetes Common Name(s) Marigold Plant Type Annual Flower Native Area South America Hardiness Rating H2 Foliage Deciduous Flowers Daisy-like single or double flowers When To Sow (Indoors) March, April Plant Out May, June Flowering Months June, July, August, September Another ‘Marigold,’ usually differentiated by referring to it as ‘Pot Marigold,’ is better known in the British Isles than elsewhere. This ‘other Marigold’ is from a separate genus: Calendula. Some of its varieties bear a superficial resemblance to Tagetes Marigolds, hence the confusing naming. Habitat & Growing Conditions In their native regions of Mexico, Central America, and South America, Tagetes species grow in and near forests and thickets, near villages, in fields, hillsides, shrubland – in short, wherever it is at all possible for vegetation to grow.4 These are tough plants and adapt themselves to a variety of soils and climatic conditions, a fact demonstrated by Tagetes species easily naturalising themselves to numerous regions where they have been introduced, including large swathes of Asia and Africa. A Planting of Golden Marigolds Decorates a Busy Road in Mexico City The only habitats they cannot conquer are cold and frigid regions as they are frost-tender with a Hardiness Rating of only H2. ‘African Marigolds’ can and do grow in hotter and dryer locales than their ‘French’ relatives. How To Grow Marigolds Marigolds of many varieties are among the most easily-found plants at nurseries and garden centres. They are commonly sold as plug plants in trays and young plants in small pots. While brick-and-mortar outlets also sell Marigold seeds, the widest variety of seeds are found online at specialist merchants. If growing yourself, use a sterile potting mix in small biodegradable pots for easy transplanting and to build in some flexibility. See our guidelines for growing from seed for more information. “I find that if you’re going to grow marigolds, you have to commit to them,” shares Master Horticulturist Peter Lickorish. “I’m not just referring to the attention needed to keep out invading slugs, but also the fact that marigolds do not mingle well with other ornamental plants. “They’re a great companion crop for vegetables, but I find that in a mixed border, they will get swamped by other plants, especially, in the case of the more delicate, Tagetes patula. “It is better for flowering displays to devote an area to having a large swathe of them, and they will richly reward you. By the same token, mixing the two main species will usually result in Tagetes erecta dominating. “To add interest, consider having the odd taller plant dotted among them, such as a dark-leaf Cordyline, to harmonise with their dusky tones.” Care & Growing Guidelines Transplant outdoors after there is no danger of frost. Space the young plants per the spread and needs of the variety in question. Preferred Aspect Regardless of whether you sow Marigold seeds directly outdoors or transplant them later, in the UK they should be sited in full sun. In the sunnier, warmer regions of the country they can be sited where they get filtered or dappled sunlight in the afternoon. Soil Requirements The soil should be a light and moderately fertile loam. Good drainage is preferable and is a must if the soil is at all clayey or otherwise heavy. For such popular and pretty plants, Marigolds are amazingly low care. They are unfussy about the type of soil and also the pH. That said, the plants will perform best if the soil is amended with some organic compost and the pH is between 6.0 and 7.5. Water them about weekly but more often in dry and hot weather. Though you do not need to water at soil level, do not allow water to fall on the flowerheads. As densely packed as they are, they are prone to rotting if they become wet. Feeding Marigolds in the ground do not require fertilising after planting but a light feeding of slow-release 0-10-10 fertiliser just before the start of the flowering season will give the blooms to come that added boost. Do not feed Marigolds with a balanced fertiliser. Pruning Some T. erecta varieties have a habit that can only be described as a ‘lanky habit’ (though a few others actually have a bushy habit). They shoot up, produce a flower, and only then start to branch. To foster bushy growth, after the plant is about six weeks old, pinch out the leader just above the topmost leaf node. T. patula varieties are compact and bushy to begin with, and need not (or should not) be pinched. Regardless of whether or not you pinch a T. erecta variety, keep an eye on it. If it gets droopy, which can happen at any point in the plant’s life, you should stake it. Common Problems African Marigold varieties can be attacked by glasshouse red spider mites and may ‘catch’ powdery mildew. Glasshouse red spider mites must be taken care of with haste. The good news is that you have a choice of treatments – newer biological controls include predatory mites and a predatory midge. Under glass, raising the humidity can help reduce infestations. It is not only humans who like the piquant taste of Marigolds, slugs and snails enjoy eating them too; at least these pests are not too difficult to control. Background & Origins Tagetes species originated from the regions of Mexico and Central America and naturalised in South America and the region of the American South-West, where they are now considered to be native. Courtesy of the Spanish conquistadors, plants were sent to Europe as early as the Sixteenth Century. Marigolds are Commonly Seen at Roadside Stalls near Temples in India Carl Linnaeus described the genus in his Species Plantarum in the 1750s. Later, French floriculturists started to develop T. patula in a big way; as a result, colloquially this species came to be called ‘French Marigold’. References 1. Doctor, V. (2017, October 20). Marigold: The Mexican flower that has become a part of Indian festivals. Economic Times Blog. Retrieved March 21, 2023, from https://economictimes.indiatimes.com/blogs/onmyplate/marigold-the-mexican-flower-that-has-become-a-part-of-indian-festivals/ 2. Tagetes. (n.d.). Kew Royal Botanic Garden. Retrieved March 21, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:325872-2 3. Tagetes (marigold). (n.d.). Native Plant Trust: Go Botany. Retrieved March 21, 2023, from https://gobotany.nativeplanttrust.org/genus/tagetes/ 4. Harris, S. (n.d.). Tagetes species. Oxford University Plants. Retrieved March 21, 2023, from https://herbaria.plants.ox.ac.uk/bol/plants400/Profiles/st/Tagetes
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Frost Tender But Remarkably Fuss-Free - Gazania 'Treasure Flower' Growing Tips
IN THIS GUIDE Overview Habitat & Growing Conditions How To Grow Gazania Gazania Plant Care Common Problems Buying Gazania References So colourful, so bubbly, so attractive, Gazanias are almost cartoon flowers! They are small, evergreen perennial plants that are frost-tender but are remarkably fuss-free and easy to grow. Bearing flowers in every hue of the warm spectrum, they will bring good cheer to any garden. Visualise the simple, innocent charms of the daisy with its wide-open corolla, ray florets, and disk-shaped appearance and add brilliant, warm colours laced and streaked with bright hues in other shades, and you’ve visualised Gazania, which is one of the ‘African Daisies’. These flowers also exhibit the charming habit of curling up for night and in overcast conditions. Evidently Gazanias like their beauty sleep! Overview Botanical Name Gazania Common Name(s) Treasure Flower Plant Type Perennial Native Area Africa Hardiness Rating H2 / H3 Foliage Evergreen Flowers Daisy-like flowers When To Sow February, March, April Flowering Months June, July, August When To Deadhead July, August Gazania is a genus within the Aster Family of daisy-like flowering plants and has 19 accepted species.1 There are a hundred-plus cultivars whose flowers exhibit vibrant colour-tones and dazzling designs, so to speak. Colours are predominantly in the warm range of the spectrum, ranging from yellow through red including pink. Perhaps it is because of the brilliant, jewel-like hues of the blooms that this plant is also called ‘Treasure Flower’. The size of the flowers, depending on the variety, ranges from 6-12cm across, with most falling in the 8-10cm range. The flowers are single or semi-double and, like Aster-Family flowers, many-petalled. These ‘petals’ are technically florets – ray florets – because the ‘flowers’ are actually composite flowerheads. What sets them apart from other members of the Aster Family is that many varieties either feature splashy radial striping on the petals or a central dark zone which is usually quite large and prominent. They typically start blooming near the end of spring. The cheery flowers and ‘cool’ foliage are components of what is a sporting, happy-go-lucky plant that is no trouble at all to grow and keeps free from pests and disease but attracts butterflies and birds like there’s no tomorrow. In fact Gazanias are so easy to grow that to all intents and purposes they grow by themselves, and so much so that they are – perhaps a little unfairly – classified as weeds in Southern California, Australia and a few other regions.2 Most Gazania varieties bloom between mid-spring and mid-summer though under the right conditions several varieties bloom right to the end of summer and sporadically in autumn. Habitat & Growing Conditions Gazanias are denizens of sunny, hot and dry conditions and they make do quite well in poor soils in their native habitat of Southern Africa.3 This should not be taken to imply that they should be treated without care but it does mean that they should not be ‘over-cared’ for; specifically, they should not be planted in rich humusy soils or manure, not be over-watered, and not be fertilised except, perhaps, very sparingly in mid-spring. In their native region, Gazania species grow freely in open woodlands, grasslands, scrublands, and semi-arid regions. These plants are invasive in favourable conditions, such as those outlined above. Another habitat it favours is coastal regions as it takes very well to salt-sea spray. Hardiness As most species hardy to H2 and most cultivars hardy to H3, Gazanias can be perennial plants in the United Kingdom with a lot depending on the specific region of the country and the spot in the garden that they are placed in. In the North / Midlands in an exposed location, Gazanias are grown as annuals. Down South by the sea in a sheltered spot, they can often be grown as perennials. In fact, Gazanias are particularly suited to coastal conditions where they also bring an ecological benefit as they control erosion in sandy and dune areas.4 G. rigens How To Grow Gazania Where you plant and how you ‘deploy’ Gazanias is strongly predicated on where you are located (in the United Kingdom) in that whether or not Gazanias can be grown outdoors as perennials. The cultivars of the Kiss Series are one H rating more cold-hardy than the species, unlike those of the Talent Series they are evergreen, and they are decumbent, mat-forming types. As such, they can be grown as a hugely attractive groundcover and can be used to great effect in mass plantings on embankments and slopes, especially in the southern, coastal areas of the country. G. ‘Christopher Lloyd’ They are also wonderful choices for growing in hanging baskets and balconies as their trailing habit will produce a cascading, ‘flowing’ effect. Clumping varieties that have a long blooming season, such as ‘Tiger Stripes’ are just as terrific for borders and edging, especially along walkways. They are also very fine companions in beds with statelier plants whose blooms would contrast strongly with those of ‘Tiger Stripes’ or other Treasure Flowers (though the plants’ different water needs would have to be managed). ’Tiger Stripes’ These little plants are great choices for a sunny windowsill or balcony. No matter which part of the country you are located in, Gazanias will make cheerful annuals be they grown in beds or pots. Gazania Plant Care Gazania is one of those rugged plants that may not respond well to TLC. Conversely, it will positively thrive if treated with ‘tough love’! Accustomed to the heat and sun of Southern Africa and acclimated to dry conditions and poor soil, Gazanias are very easy to grow and need little care as to heat and soil type. The only point on which they need care is extremes of cold as they are frost tender. Preferred Soil The optimal soil for Treasure Flowers is a sand-based loam that is not overly-rich with manure or compost. It must drain very well – these plants do not thrive in moisture-retentive soils. The ideal soil pH is from slightly acidic to neutral, though this plant will be content in soils with pH from moderately acidic to slightly alkaline. Aspect In the UK they should be located in full sun. Gazanias may be started from seed in containers indoors in winter, and transplanted outdoors or moved outside after there is no danger from frost. The advantage of potted Gazanias is that you can move them back indoors at the end of autumn. If they are kept toasty in a greenhouse or any warm spot indoors, they will survive the winter – however, they must get ample sunlight. Before transplanting or moving potted Treasure Flowers outside, they should be hardened by putting them out during the day and back indoors for progressively longer durations. Propagation Gazanias are just as easy to grow outdoors from seed, again after there is no danger from frost. You need do nothing more than push seeds just a tad into the soil and water them…and watch them sprout. You can also propagate this easy-to-grow plant from basal softwood cuttings. Take cuttings from late summer to mid-autumn and plant them in sand-based loam with additional compost or a potting soil in pots. They should be kept indoors or in a greenhouse through the winter but they must get sufficient sunlight. They can be transplanted outside in spring. Whether you grow or transplant Treasure Flowers outdoors, space them 50-70cm apart. “While Gazanias can be propagated by division, they have a tendency to become woody and less floriferous when divided,” shares Roy Nicol, a Master Horticulturist. “So, starting in the spring with over-wintered cuttings means fresh, vigorous plants which will flower well over the summer and into the autumn.” Watering Gazanias are drought-tolerant but not ‘damp-tolerant’. Sprinkle water moderately, even in summer – water when the soil has become dry and avoid over-watering these plants. In some rainy regions of the UK you may not need to water outdoor Gazanias for weeks on end. Pruning Treasure Flower plants do not need pruning except for regular deadheading. “It can be tricky to spot which flowers are spent when all the flowers are closed up in the morning and evening,” adds Roy. Therefore, it’s easiest to deadhead during the day when the flowers have opened in the sunshine – spent flowers don’t open, have long stems and can be pinched out. “Watch out for new flowers which also may not have opened yet but are close to the base and still with short stems.” G. ‘Big Kiss Yellow Flame’ However, if you grow trailing or decumbent varieties as groundcover or for a cascading effect, you should judiciously prune, and also train, the plant for shaping and landscaping. Upright or straggly growth should be removed and the plant should be trained and pruned to develop along the ground, or over and down the rim of a basket. Common Problems Gazanias are valued for being resistant to pests and for being disease-free. Occasionally a plant may be attacked by aphids or grey mould, particularly if it is brought indoors or kept in a greenhouse for the winter. Damp soils may lead to root rot. Buying Gazania The United Kingdom was one of the first regions in Europe where Treasure Flower was naturalised, and it remains one of the few countries in Europe where this plant is available at garden centres, if not very widely or in full variety. Potted plants are available, usually in spring, in garden centres and nurseries. Varieties of the Kiss Series and Talent Series are more widely available than most. A very good option is to buy Gazania seeds online. References 1. Gazania. (n.d.). Kew Royal Botanic Gardens. Retrieved March 16, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:331621-2 2. Gazania spp. (2017, March). Gazania Weed Management Fact Sheet. Retrieved March 16, 2023, from https://cdn.environment.sa.gov.au/landscape/docs/hf/gazania-weed-management-fact-sheet.pdf 3. Gazania rigens. (n.d.). Missouri Botanical Gardens. Retrieved March 16, 2023, from https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=a517 4. Gazania spp. Gazania. (n.d.). Eyre Peninsula Landscape Board. Retrieved March 16, 2023, from https://cdn.environment.sa.gov.au/landscape/docs/ep/EPLB_Gazania_Plan.pdf
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Nasturtiums Are Resilient Low-Care Climbers: Here's How You Can Grow Them Each Year
IN THIS GUIDE Overview Habitat & Growing Conditions Planting How To Grow Nasturtiums Plant Care Pruning Common Problems References Tropaeolum, commonly called Nasturtium, is a genus of climbing, sometimes creeping, plants that have fantastic ornamental value in terms of their heights and spreads, foliage and flowers. These rather unusual plants typically have a very long blooming season, and their flowers come in an astonishing variety of colours from icy blue to blazing red. “I grow nasturtiums every year,” says Gardener Hannah Reid. “I love nasturtiums for their beautiful flowers and leaves. An additional bonus is that the entire plant is edible – flowers, foliage and seeds, which are amazing pickled!” It is not to be confused with Genus Nasturtium which encompasses Cress species. Nasturtiums are unusual plants on several counts: First, most of them are resilient, if not always strong, climbers though a few have a bushy, spreading habit. Second, their foliage is both uncommon and attractive. Third, their brilliant flowers are even more attractive; what’s more, they bloom for months on end. Fourth, they are very low-care plants. Fifth, they are effective companion plants to a whole host of edible plants. Taxonomically there is a connection to the abovementioned Cress because both Genus Tropaeolum (‘Nasturtium’) and Genus Nasturtium (Cress) fall under Order Brassicales, many of whose members are edible and which have a tangy, peppery, or pungent flavour, with Mustard probably being the ‘Head of the Family’.1 As it happens, Nasturtium flowers and leaves are edible and lend a piquant zing to salads and even soups. Out of Rocket? Not a problem if you have a Nasturtium in the garden. Overview Botanical Name Tropaeolum majus Common Name(s) Nasturtium Plant Type Annual Flower / Climber Native Area South & Central America Hardiness Rating H3 Foliage Deciduous Flowers Commonly red, yellow or orange When To Sow March, April, May Flowering Months July, August, September, October Though Nasturtiums are deciduous perennials, in most regions of the United Kingdom they are half-hardy and are grown as annuals. However, along the south-western coast and a few other regions, several varieties can be grown as the perennials that they are (though a few varieties, such as T. tuberosum and T. speciosum, can be grown as perennials in almost all regions of the UK). If you are lucky enough to call a relatively balmy region home, you can bring great joy to your garden by growing arguably the most ornamental of all climbers. T. majus To begin with, the foliage is of a mellow sea-green colour. The leaves are decorative in their own right, being either lobed, often deeply, or rounded and shield-shaped. The showy flowers come in hues of yellow, orange and red, but a few are in shades of blue and purple and some are also bi-coloured or variegated. To top it all off, Nasturtiums bloom for months on end, many varieties are fragrant, and the flowers attract butterflies and hummingbirds! Habitat & Growing Conditions Tropaeolum grow in the wild from south-eastern Mexico and Guatemala in the north to the tip of Patagonia in the south, excluding Brazil. Some species grow at altitude in the alpine regions of the Andes while others grow in lowland coastal areas; Chile is a particular centre of species diversity.2 T. majus ‘Empress of India’ What is common to all of them is that they are indifferent to soil – as they grow in soils ranging from average down to what can only be typically considered very poor. They are usually found growing in full sun; though their water needs are low they do best in moist soil. The vast majority of Nasturtium species are frost-tender and are hardy (only) to Zone H3. A few species, though, are frost-hardy down to Zone H5. T. speciosum Planting Most Nasturtiums are climbers that attain heights of about 3m. A few, such as T. speciosum and T. peregrinum, can reach heights of up to 4m. An overgrown Nasturtium climber along the wall of a house will impart a charming, country-cottage effect to your urban dwelling. They will produce the same countryside charm when they climb up and wash over boundary walls and fences with next to no training. The shorter, more delicate, Nasturtiums, for example T. azureum, are ideal to plant beside summer-houses, especially when the walls are of latticework – then a few flowers and leaves will ‘peek’ inside. Some Nasturtiums have a spreading, bushy habit. Examples include T. majus ‘Empress of India’ and T. majus ‘Chameleon’. If grown in large planters these species will add great colour and produce a delightful billowing effect by the patio or on the porch. They can actually be used to create borders as well. How To Grow Nasturtiums Nasturtium seeds of the spreading, trailing varieties, are widely available at nurseries and online stores. In addition, seeds of the more popular climbers, for example T. speciosum, are just as freely found. Some, such as T. majus ‘Chameleon’, are much harder to find. Because species of this genus do not take well at all to transplanting, only a few varieties, such as the bushy, spreading varieties, are available as plants in containers from a limited number of garden centres. If you already have a Nasturtium, you may be able to get new Nasturtiums for yourself and your friends. Some species self-seed very reliably. You can often simply let the flowers wither and then harvest the seed pods. Plant Care Most, if not all, Tropaeolum varieties can be grown reliably from (the rather large) seeds. One may as well add that they will just as reliably start to wilt and wither if transplanted. Therefore, do not start these plants in pots for later transplanting though you may very much grow and keep short and spreading varieties in planters. Soil Requirements Besides being very transplanation-averse, these plants have yet another quirk. They do best in poor soil! The richer the soil, the more foliage they will produce at the expense of flowers. A mix of gravel, chalk, and sand with but a sprinkling of humus or manure mixed in will be perfect though any old soil will do. Soil pH hovering around neutral is ideal though any pH from moderately acidic to slightly alkaline will do fine for most Tropaeolum varieties. The one non-negotiable is that soil should drain very well. Watering These plants should be watered about twice a week, be it from the rains or the hosepipe. When the soil dries out, it is time to water them. Younger plants need more regular watering than established outdoor ones. Feeding Avoid fertilising Nasturtiums of any kind. Nitrogen-high fertiliser especially should be avoided because it will spur growth of foliage on an already leafy plant; in turn, this will negatively affect the number and size of blooms. T. majus ‘Jewel Cherry Rose’ Indeed, even a balanced fertiliser would not be a smart idea for Nasturtiums under most circumstances. Overwintering If you have grown a Nasturtium as a perennial in the UK, then, if it is of a type that is dormant in winter and is not frost-hardy (the majority of varieties), soon after the leaves have shed in autumn, you should spread a layer of leaf mulch on the soil above the root system. Remove it a couple of weeks after the last frost of winter. Pruning In general Nasturtiums do not need to be pruned as they are deciduous plants (assuming you can grow them as perennials and not as annuals). “Nasturtiums are so vigorous that, unless you are happy for them to be rampant, you will need to cut back the stems,” shares Horticultural Consultant Colin Skelly. “Just cut back stems to just above a leaf and your Nasturtium will happily keep growing around whichever area you want clear.” In general, the bushy spreading varieties may be cut back soon after the flowering season is over. Climbing varieties can be deadheaded to encourage fresh blooms. T. majus ‘Black Velvet’ Don’t get caught out by the flowering season and dormancy season of your Nasturtium variety; keep in mind that T. azureum, T austropurpureum, and T. tricolor are all dormant during the summer and bloom in winter and spring. Common Problems Tropaeolum is an inherently healthy genus and is known to stay free of disease but the different varieties have varying susceptibilities to pests. In general, the shorter Chilean climbers are the most robust while T. majus and its varieties are the least robust. Both T. speciosum and T. peregrinum may be attacked by flea beetles and caterpillars with the former also a target for blackfly and the latter for aphids. T. majus and its cultivars are susceptible to blackfly, flea beetles, and caterpillars, in addition to which a lesser threat is posed by slugs. References 1. Nasturtium (water-cress). (n.d.). Native Plant Trust: Go Botany. Retrieved March 21, 2023, from https://gobotany.nativeplanttrust.org/genus/nasturtium/ 2. Tropaeolum majus. (n.d.). Kew Royal Botanic Gardens. Retrieved March 21, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:310974-2
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