Growing
"A Wonderful Sense Of Achievement" - The Flowers Gardeners Love To Grow From Seed
IN THIS GUIDE 1) Snapdragons 2) Hollyhocks 3) Scabious 4) French Marigold 5) Gerbera 6) Primrose 7) Pansy 8) Sunflower 9) Garden Nasturtium 10) Sweet William 11) Pot Marigold 12) Cosmos 13) Zinnia 14) Pelargonium (Geranium) In this article we identify fourteen ‘fab’ flowers which are a walk in the park to grow from seeds. No need for some special type of soil, specific watering needs, fertiliser requirements, particular sun-shade mix, staking and support canes, or recurring pruning duties. All of the following flowers germinate reliably from seed and are low-care to no-care ornamental plants. “Growing from seed is a surprisingly simple process and is achievable by anyone regardless of their experience, whether if they have a garden, an allotment or even a greenhouse,” says Horticulturist and Garden Writer Joe Harrison. “All you need is somewhere light and warm (such as a kitchen windowsill), a tub, container, pot or tray, compost and a little patience.” Here is a general guideline (though certainly not a hard-and-fast rule): For any given flowering plant, all other things being equal, newer or more unusual cultivars are least easy to grow and require the most care, whereas seed packets with the word ‘mix’ are the easiest and simplest to grow and will germinate the most consistently. Most of our selections, both annuals and perennials, are notorious self-seeders so where the annuals are concerned consider not deadheading on a continual basis and allow some number of the blooms to wither and go to seed; then, the following season you will be rewarded with a fresh batch of plants without sowing a single seed! “Growing from seed is so easy and so rewarding if you are able to give it the time, and you can find so many new and interesting plants, especially annuals,” shares Garden Writer Clare Foster. If you have good quality seeds, halfway decent soil, and regular rainfall, all you need do is to sprinkle-sow seeds of the following flowering plants – and forget about them. “I think seeing a seed put out a tiny leaf and then transform into something ridiculously beautiful is just one of the most amazing things ever,” shares Gardener Karen Liebreich. “My secret tip would be to notice how amazing nature is and to cherish and nurture it. It desperately needs our help.” At least some will germinate and put up lovely blooms. “It is worth noting that sometimes seeds will fail to germinate and if your seeds do germinate, sometimes the seedlings will die for seemingly no apparent reason,” shares Joe. “This is perfectly normal, albeit very disappointing, and can and does happen to even the most experienced gardener, so don’t get too disheartened when this occurs.” What has been stated is neither an exaggeration nor a recommendation – it is a simple statement of fact to get across the reality that some flowers are really, really easy to grow from seed. However, if you take just a little time and trouble over sowing and growing (have a look at our gardening guides), you’ll increase your chances of getting delightful flowering plants to nearly 100%. “I might not grow them every year, but there are several favourites that I like to grow from seed for the simple reason that they are foolproof, yet still give that wonderful sense of achievement,” shares Sunil Patel, owner of 13 Broom Acres garden. “Aquilegia, delphiniums, calendula, Swiss chard and basil can be a success story without even thinking. “I can fall back on these as a pick-me-up when other, more difficult seeds have either failed or succumbed to rot, pests or bad weather.” We have tried to sequence our own Fab Fourteen in ascending order of ease of growing; that is, this list progresses from easy to easier to easiest. We also suggest a couple of seed varieties for each flower. 1) Snapdragons BOTANICAL NAME: Antirrhinum HARDINESS RATING: H3 RECOMMENDED VARIETIES: ‘Antiquity’, ‘Chuckles’, ‘Day & Night’ This plant bears irregularly shaped flowers each of which resembles a mythical beast’s head. Squeezing and releasing the sides of the flowers causes the ‘jaws’ to open and close – a little childhood delight that the inner child may never get tired of! The colours are traditionally in pale, pastel shades in yellows and pinks, and also in bright lilacs and purples. Snapdragons come in both annual and perennial types and have a very long flowering season from June even up to October. Though some tall varieties are upright and have stoutish stems, others are limp and floppy; these require staking and are not recommended for the purposes of this article. 2) Hollyhocks BOTANICAL NAME: Alcea rosea HARDINESS RATING: H5 RECOMMENDED VARIETIES: ‘Las Vegas Mix’, ‘Chater’s Mix’, ‘Black Knight’ Hollyhock flowers are open and bowl-shaped with broad petals. They occur mainly in the pink through purple spectrum, with yellow and crimson being less common colours. The plants are very tall and stately yet they are naturals for cottage gardens. Their upright and narrow profile makes them a top choice for small gardens too. Annuals, biennials, short-lived perennials – Hollyhocks are said to be all those things and, in fact, their lifetime depends on the particular variety and the climatic zone it is grown in. But what is for sure is that they are excellent self-seeders so you don’t have to worry about them ‘coming back.’ They bloom for 2-3 months in summer and autumn. Hollyhocks can succumb to rust but rust-resistant varieties like Alcea ficifolia are available. 3) Scabious BOTANICAL NAME: Scabiosa HARDINESS RATING: H4 RECOMMENDED VARIETIES: ‘Tall Double Mix’, ‘Blue Note’ Scabiosa, also known as Scabious, have densely-packed dome-shaped flowerheads in double form with cutely wavy and bent petals but their distinctive feature is the central ‘pincushion’ disk. Mostly found in the pink through purple colour range, blue and maroon-black cultivars are probably the most riveting. Copious numbers of blooms are produced from July through September, and these nectar-rich flowers are just magnets for bees and butterflies. Compounds made from the flowers have long been used to treat skin conditions and also other diseases. They are as perfect for cottage gardens and beds, usually as companion plants, as they are for vases. Scabious are perennials as such but in the United Kingdom they are effectively annuals. 4) French Marigold BOTANICAL NAME: Tagetes patula HARDINESS RATING: H2 RECOMMENDED VARIETIES: ‘Fantasia Mix’, ‘Durango Mix’ French Marigolds were cultivated in France from plants originating in Central and South America, hence their name. These are the shorter and bushier types of marigold with a smaller flower, and are also among the healthiest and most resistant types. Flowers occur in both single and double form, and their colours range from rich yellows through scarlet and rose red with an amazing variety of golden and orange hues. Several varieties are bicoloured in yellow and orange. French Marigolds are unbeatable choices for mass plantings and mixed beds. They are annuals with a very long flowering season – while some will get started in late spring and others go well into autumn, almost all will bloom all summer long. 5) Gerbera BOTANICAL NAME: Gerbera HARDINESS RATING: H3 RECOMMENDED VARIETIES: ‘Hardy Sweet Mix’, ‘Cut Flower Mix’, ‘Fleurie’ Gerberas occur in both single and double form and are daisy types of flowers with numerous narrow rays. The single forms exude a charming innocence with the disk shape prominently displayed while the double forms are convex and lush. Available in yellows and pinks through crimson, single forms are best appreciated in white and pale, pastel shades; double forms look best in deep, vivid hues. Depending on your location in the United Kingdom and the variety, this plant can be an annual or perennial. Blooming virtually year-round in subtropical zones, in the UK many varieties will put on their respective colour shows from mid-spring clear into autumn. If you want to introduce a child to the pleasures of gardening, Gerbera is one of the top few choices. They make terrific pot plants and are quite possibly the most engaging and longest-lasting of cut flowers. 6) Primrose BOTANICAL NAME: Primula HARDINESS RATING: Varies RECOMMENDED VARIETIES: ‘Springtide Mix’, ‘Provence Mix’, ‘Danova Series’ Many Primula Primrose varieties are simple, cheery flowers displaying lovely petals that are wide, slightly creased, and with that ‘patented’ distal notch. The flowers occur in virtually every colour in both the cool and warm spectrums, so you get it all: pastel-shade cool blues and lavenders, and saturated and vibrant oranges and reds. Most of them have that other patented Primrose styling: a bright yellow centre. They are perennials, and may be deciduous or evergreen. Well known harbingers of spring, some varieties start blooming in December while others start late and continue into June but all will give you something uncommon: bright blooms that beat the swallows to spring. Finally, Primrose is surely the defining plant of an English country garden – or even townhome garden! 7) Pansy BOTANICAL NAME: Viola HARDINESS RATING: Varies RECOMMENDED VARIETIES: ‘Aalsmeer Giants’, ‘Universal Super Mix’ Among the easy-grow flowers, Pansies are a special joy because they are among the very few cold weather plants that can be grown effortlessly from seed, and also grow automatically as they are very reliable self-seeders. The flower’s face is vertically oriented and even has an ‘up’ and ‘down’ side! Many of them display a ‘face,’ which is an especial joy for children. As for the colours, these bicoloured and multicoloured flowers throw up hues and tones that are among the most diverse and fantastic among all Flowerdom as they cover the entire colour spectrum. Pansies are effectively annuals and they are among the first flowers to bring cheer to the garden as they emerge in earliest spring and bloom very soon thereafter. New self-seeded plants bring up unpredictable and incredible colour combinations. Ideal for borders and edging. 8) Sunflower BOTANICAL NAME: Helianthus annuus HARDINESS RATING: H4 RECOMMENDED VARIETIES: ‘Stella’, ‘Cut Flower Mix’ Well known the world over for their large flowers that ‘follow the sun’ and the spanking bright-yellow petals that surround a black-brown central disk – the seedhead – Sunflowers are among the healthiest and most robust of flowering plants. Many varieties can tolerate different climatic conditions. Giant varieties are exceptionally tall reaching even 6m; at the other extreme, even dwarf varieties suitable for pots are available! For the most part varieties afford a choice of some shade of yellow for the petals and a choice of browns for the disk, but some cultivars’ flowers open to unusual and attractive dark rust and maroon shades. Sunflowers are often planted along the boundary of one’s property and can also be grown in pots. They bloom through the summer and the first half of autumn, and they come in both perennial and annual types. 9) Garden Nasturtium BOTANICAL NAME: Tropaeolum majus HARDINESS RATING: H3 RECOMMENDED VARIETIES: ‘Jewel Mix’, ‘Tom Thumb Mix’ Garden Nasturtiums of the Tropaeolum genus come in bushy, climbing, and trailing habits. As easy-grow, no-care plants we recommend Garden Nasturtiums of bushy or mounding habits. They produce very attractive funnel-shaped flowers in vivid yellows, oranges, and reds. The broad petals are wonderfully veined and creased which is a special feature of these flowers. These plants have quite a long flowering season, typically throughout summer and into autumn. Though Garden Nasturtiums are deciduous perennials in fact, they are half-hardy annuals in actuality in most regions of the United Kingdom. “I once grew Nasturtium in a vegetable bed for the edible flowers,” shares Colin Skelly, an RHS verified Master Horticulturist. “It looked and tasted great but seeded around rather too freely from the large seeds which scattered all through the vegetable beds (Nasturtium will trail and run). “I still grow it, but only in areas I don’t mind it seeding around.” These plants will bring much charm and spanking colour to borders and parapet pots for which they are ideal. And if you want to eat these delightful flowers or the leaves, guess what? You can! 10) Sweet William BOTANICAL NAME: Dianthus HARDINESS RATING: Varies RECOMMENDED VARIETIES: ‘Double-Flowered Dwarf’, ‘Pinocchio’ Sweet William plants have bushy, often mounding, or upright and erect habits. They are annuals and hardy biennials but the latter usually flower in their second year. The flower is small and has an open, cheery look about it and its merry charm is given an assist by those amusing zig-zag, ‘frayed’ outer edges. They are outrageously floriferous and produce gobs and gobs of flowers, both selfs and bicoloureds. They occur in hues from pinkish-white through ruby red with every imaginable shade of pink from the demurest pastel to deep magenta. Sweet William varieties’ flowering seasons vary a lot but mid-spring to mid-summer is typical. These plants are naturals for cottage gardens and hanging baskets, and are also very good for rockeries. 11) Pot Marigold BOTANICAL NAME: Calendula officinalis HARDINESS RATING: H5 RECOMMENDED VARIETIES: ‘Orange King’, ‘Kinglet Mix’ Calendulas, also known as Pot Marigolds, are annuals that produce somewhat domed, double flowers with numerous narrow rays. The flowers are not only edible, they are a well-defined ingredient in several Eurasian cuisines because of their pleasantly piquant taste. However, you’ll probably plant these easy-grow annuals, not to eat them, but, to bask in the glow these sunny disks generate in all hues of yellows and oranges, from primrose yellow to vivid vermilion. Many varieties have an unusually long flowering season, producing blooms for months and months with some varieties getting underway in mid-spring and ending in mid-autumn. They are also very floriferous plants and make a superb choice for mass plantings and also as companion plants. 12) Cosmos BOTANICAL NAME: Cosmea HARDINESS RATING: H3 RECOMMENDED VARIETIES: ‘Brightness Mix’, ‘Sensation’, ‘Choca Mocha’ Cosmos are among the most satisfying of easy-grow low-care plants for multiple reasons. To begin with, the bloom lasts for a long time on the plant and even the cut flower lasts forever in a vase. Next, they tolerate heat and dry soils better than the vast majority of other plants, even as they produce sizeable and very attractive flowers. And, oh, they have a long flowering season running for months at a stretch, from spring into autumn. Cosmos have wide open disk-shaped daisy-like flowers with wideish petals that have multiple notches at the distal end – simple and sweet. Traditionally single form, some semi-double varieties are also available. Flowers occur in all colours and all shades of the warm spectrum plus white, and are excellent for mass plantings in beds. This plant is an annual and is a reliable re-seeder. 13) Zinnia BOTANICAL NAME: Zinnia HARDINESS RATING: H2 RECOMMENDED VARIETIES: ‘Bright Spark Mix’, ‘Lilliput Mixed’ Zinnia, our Silver Medallist and runner-up, produces semi-rounded double flowers with densely-packed rays. Colours are almost always in brilliant, saturated tones in the warm spectrum. This amazing flowering plant has a rare virtue in which it probably leads the pack. You can keep cutting flowers and put them in vases in the home, where they are very long-lasting – and the more you cut, the more new buds the plant will produce. Heat and dry weather do not deter these plants. Another merit is that they flower prolifically yet have a long flowering season – all of them bloom all summer long with many getting started in spring, winding up in autumn, or both! Remember to let a goodly number of flowers wither and go to seed: Zinnia is a tender annual but a terrific self-seeder so your dying flowers will give you a fresh set of plants the following year. Some cultivars also make great accent plants in containers. 14) Pelargonium (Geranium) BOTANICAL NAME: Geranium HARDINESS RATING: H7 RECOMMENDED VARIETIES: ‘F1 Magic Beauty Mixed’, ‘Super Hybrid Mix’ Occupying Gold Medal position, Pelargoniums are not the country’s favourite perennial without good reason. They possess all the virtues of the plants listed above – including being tasty culinary ingredients – and they don’t even need good soil. On top of that they even stifle weeds and repel pests! Though there are many types of Pelargoniums with numerous plant habits and even floral forms, the easy-grow mix varieties that we propose have bushy, clumping habits. Pelargonium flowers may be saucer-shaped or bowl-shaped and occur in single, semi-double and double forms. Their petals are wide, overlapping and notched; flowers are borne in sprays and clusters. The hybrid and ‘mix’ seeds of these long-lived perennials give rise to flowers in an array of yellows, pinks, oranges, purples, and reds. These plants bloom profusely and do so for months on end – while they bloom all summer long, in favourable conditions they will start in mid-spring and end in mid-autumn.
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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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Olives Respond Very Well To Pruning: Encourage Fruiting And Keep Your Plant In Check
IN THIS GUIDE When To Prune Olive Trees Do They Need To Be Pruned? Maintenance Pruning Pruning For Fruit Pruning To Restrict Size & Preserve Form Olive trees are beautiful Mediterranean trees that can look wonderful in a sheltered, warm spot here in the UK, but learning how to prune them correctly is important. When and how to prune your olive tree and the reasons for doing so, will vary depending on why you are growing your olive tree, where you are growing it and what precisely you are aiming to achieve. Olive trees can be beautiful trees to grow in a warm, Mediterranean-style garden. Understanding how to care for your olive tree correctly is important and that includes understanding how and when to prune the tree. When To Prune Olive Trees First of all, whenever pruning an olive tree (for whatever purpose and with whatever goal) it is important to choose the right time for the job, as Paul Smith from The Norfolk Olive Tree Company explains: “Like most evergreen trees, Olives respond very well to pruning. In fact, the more you prune, the happier they’ll grow”. “However, is best to prune your Olive Tree after the last of the winter frost, from March onwards, and before the first autumn frosts, which is usually between late October and early November”. Typically, you will prune an olive tree between late spring and the end of summer. It is important not to prune your olive during the winter, as this can make the tree more vulnerable to infection with disease. Always prune over the warmer part of the year to reduce the chances of disease taking hold. Unfortunately, olive trees can be rather prone to a number of diseases, especially in a cooler climate. Pruning incorrectly and at the wrong times can make it more likely that one will take hold. Some only slightly impact the appearance of the tree, but some diseases could actually kill your olive tree outright. Do They Need To Be Pruned? Though pruning can often be a good idea, olive trees are relatively slow-growing and should not need a lot of pruning at all in most scenarios. However, it is important to note that it is good practice (with an ornamental olive tree) to remove any dead, damaged or diseased materials as part of general care and maintenance. If you are trying to grow an olive for its fruits, then the pruning considerations are somewhat different. This is not always very easy in the UK, as the trees will typically only fruit in the mildest and warmest of UK gardens. And even when the fruits do set successfully, you will still have to harvest the fruits before the first frosts and cure them before they are used. Curing is essential if you want olives that taste like those you can buy in the shops. Bear in mind that these trees thrive in the hot, long growing season of the Mediterranean and so work will be required to obtain an edible yield in our climate, with our much shorter growing season. Another consideration is that here in the UK, olive trees are often grown in containers, and some pruning may be required for container-grown trees to keep their size in check and to stop them from outgrowing a container. In short, therefore, you might wish to prune olive trees: For simple maintenance. To encourage fruiting and promote new fruit production. To keep the size and shape of the tree in check. However, while olive trees can respond well to pruning, it is important not to go overboard. Prune too excessively and the tree may put forth numerous water shoots (not fruiting growth). This is not ideal if you are trying to produce fruit, of course. It can also detrimentally affect the overall appearance of your olive tree. Olives should usually be pruned quite lightly in order to preserve a more natural appearance, as Paul Smith advocates: “Light and more light is the overwhelming principle of pruning. If you prune back your Olive Tree hard, this will result in a dense growth, whilst a light, formative prune will give your tree a natural shape. “Also, letting the light into the tree improves fruit production and letting in the light also keeps the tree under control. “If the tree is dark and dense, branches will race up and out to find more light, making the tree leggy”. Maintenance Pruning Usually, if an olive tree is growing in the ground, light, maintenance pruning is all that will be required. Simply remove any branches which are causing damage by rubbing on one another, and any which have been damaged over the winter months in late spring or early summer. At the same time, you may also prune some branches at the centre of the canopy to let more light in to new growth, and remove a side branch or two to maintain a pleasing shape. But do not overdo it – less is usually more when it comes to maintenance pruning on an olive tree that is grown for ornamental reasons and not for its fruit. Dan Ori recommends: “If you are not worried about impacting the fruiting, young olives can be trained and trimmed into attractive loose lollypop shapes; you will often see pairs of lollypop olives framing the doorways of opulent city homes.” Pruning For Fruit When pruning an olive tree for fruit, Paul Smith explains that one of the most important things to remember is that olives fruit only at the tips of the previous year’s growth. “The olive tree produces fruit mainly at the periphery and top of the canopy. This is because these parts of the tree are fully exposed to sunlight and in turn improves fertility. “When pruning for fruiting purposes, you should focus on the removal of any part that shades other younger parts of the tree”. Pruning too zealously can prevent fruiting. However, not pruning at all can lead, over time, to a tree with too much older wood, which may also restrict new growth and prevent light from reaching and ripening any fruits that do form on the last year’s branches. It is a good idea, therefore, to prune out sections of old wood each year to allow some newer fruiting growth to form. It is also recommended to thin fruits that form to no more than 3-4 for each 30cm of branch. This should help ensure that the olives ripen successfully and will not drop off the tree prematurely before harvesting time. “I recommend growing an olive in a pot against a sheltered sunny brick wall for the best chance of ripened olives,” says Dan Ori, a Member of the Arboricultural Association. Pruning To Restrict Size & Preserve Form Pruning to restrict size is not usually a concern when these slow-growing trees are grown in the ground. But when they are grown in containers, you may need to do some additional pruning so they do not outgrow their pot. In addition to the general maintenance pruning in the late spring or early summer, a container-grown olive may also require additional pruning in summer to restrict their size. Paul Smith suggests that if your potted Olive Tree is not thriving in its pot, you can reduce the canopy size of your tree by up to one-third to keep its size in check and restore the plant’s health. When olive trees in containers grown to around 1.5m tall, it is also often a good idea to prune to preserve or create a pleasing form. Choose a few of the strongest and best-placed branches and keep these, but get rid of other shoots. It should also be noted that you can take pruned branches in summer and use these as semi-ripe cuttings to propagate new olive trees from the parent plant. You might also pinch out the growing tips to encourage branching and a bushier canopy. Olive trees are not the easiest trees to care for and grow successfully in a UK garden, but pruning them is rarely a hugely complex business.
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Maize vs Corn: What’s The Difference? Well, They're Actually The Same Plant
IN THIS GUIDE Are They The Same Plant? Regional Dialects Maize vs Corn: What Are They Used For? Now You Know The Answers! References If we say “sweet corn” you’ll probably get a fairly strong mental image right away: bright yellow kernels, possibly clinging tight to a cob, possibly scattered liberally throughout a salad. But if we say “maize,” what comes to mind? A field of corn? A field of something else? Or maybe you have no idea at all. In this post we’ll be tackling the age-old question: what is the difference between maize and corn? Are They The Same Plant? Yes, the terms maize and corn are generally used to refer to the same plant, Latin name Zea mays.1 Maize (the most common term for the crop in the UK) is a cereal grain and is part of the Poaceae family of plants.2 This is an incredibly versatile crop that humans use for everything from food to plastic production (there’ll be more on the various uses for this plant later on). Confusion around terminology stems from the fact that they’re used differently between different dialects of English. Regional Dialects When you have a plant as widespread and tightly woven around human history as corn, it’s inevitable that there’ll be some variations in the names used in different places. The main reason people ask about the differences between these two terms is the different ways they’re used around the world. In North American English, for example, corn refers to the yellow kernels, the cob, and the whole plant. You’ll see high fructose corn syrup in pretty much every American ingredients list, whereas in the UK this would traditionally be thought of as maize syrup. In the UK nowadays corn most commonly refers to the kernels, the cob, and other food-based uses for the plant. Maize refers to the crop grown in fields, and is also used in more technical situations (scientific research and other formal settings for example). Then, just to confuse things even further, the historic use of the word corn in Europe meant something different altogether! In centuries past, corn would’ve been used to refer to the dominant crop in a region, whether that was wheat, rye, oats, or similar.3 The exact reference would vary depending on the region, but thankfully this usage has fallen out of favour over time. Maize vs Corn: What Are They Used For? Here’s where things get really interesting. While it’s not hard to think of recipes that contain corn, did you know that this crop is used for everything from the production of chemicals, to feed for livestock, to bio-fuels?4 First let’s take a look at the food uses. Corn on the cob is perhaps the most memorable corn format: a perfectly proportioned morsel with row upon row of sweet, golden kernels ready to be slathered in butter and munched. Strip the kernels and you have what most people would call sweet corn. A voluminous quantity of the bright yellow fruits that you can buy tinned or frozen and use in pretty much anything. A little extra crunch in your salad? Go for it. An enhancement to a shepherd’s pie recipe? You know it is. Something to add to your plate of sweet shaved ice? In certain Asian countries, the answer here would be yes too! Then you’ve got all the hidden uses of the maize crop: cornmeal, corn starch, corn syrup, grain alcohol, and so many others. These uses are why corn is one of the most ubiquitous foods in the world. Move beyond food, though, and maize still comes in useful in a lot of ways. Starch derived from the crop is used in the production of many types of fabrics and plastics, as well as adhesives and other chemical solutions.5 If you’re into eco-friendly tech, you can also power your car or heat your house with bio-fuels derived from maize. Corn cobs are also frequently used as decorative objects in certain regions. Leave them out to dry and the kernels harden off, taking on deep hues that look great against a rustic backdrop. And if you can believe it, we’ve barely scratched the surface here of how maize can be used. “Growing sweetcorn plants is easy, but their position in relation to each other is important, as corn is wind pollinated,” shares Horticultural Consultant Dan Ori. “To achieve the best cross-pollination between plants, you should plant multiple seeds in a grid spaced 30cm by 30cm apart.” Now You Know The Answers! No doubt now any questions you had about maize and corn have been answered, and who knew the subject could be so interesting? This plant is inextricably linked to humanity, having been a staple crop around the world for millennia. It’s no wonder we’ve found thousands of ways to use corn and maize, from food and beyond, considering we’ve lived alongside it for so long. Thanks for taking the time to read this blog post, and hopefully now you’ll be able to put your newfound knowledge to use. Possibly in a pub quiz one day, or by settling an argument at the dinner table about whether maize and corn are the same thing (hey, it could happen!) References 1. Zea mays (maize). (2019). CABI Compendium. https://doi.org/10.1079/cabicompendium.57417 2. Leszek, P., & Vincent, D. (2012). Zea Mays (Maize, Corn). ELS. https://doi.org/10.1002/9780470015902.a0003687.pub2 3. Brittain, C. (2020, July 31). Corn. Life in the Middle Ages. Retrieved March 21, 2023, from https://cdalebrittain.blogspot.com/2020/07/corn.html 4. Bioenergy Corn. (2022, March 1). CropWatch. Retrieved March 21, 2023, from https://cropwatch.unl.edu/bioenergy/corn 5. Royte, E. (2006, August). Corn Plastic to the Rescue. Smithsonian Magazine. Retrieved March 21, 2023, from https://www.smithsonianmag.com/science-nature/corn-plastic-to-the-rescue-126404720/
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When Growing Honeysuckle In Pots, These Are The Varieties And Containers To Choose
IN THIS GUIDE Honeysuckle Varieties For Pots Growing Honeysuckle In Pots Choosing Containers Potted Honeysuckle Care Common Problems References Honeysuckle is one of the easiest and most rewarding plants to grow, producing beautiful pollinator-friendly flowers, often with a heaven-sent smell that lingers in the air. Though suited to growing direct in the ground, they are also well adapted to being grown in pots and containers, so can be grown almost anywhere. For those growing in the ground, see our Honeysuckle plant care guide which will better serve your requirements. If growing in containers, please read on… Honeysuckles are botanically named ‘Lonicera’ and are part of the Caprifoliaceae family, comprising approximately 180 different species of ornamental climbers and shrubs.1 Honeysuckles can be deciduous or evergreen, and typically flower in summer to autumn, but some can even flower in winter, providing a wonderful scent in the darkest months. Lonicera caprifolium However, not all honeysuckles are scented, so it is well worth checking before growing yours. Honeysuckles tend to grow best in full sun, however, some varieties can cope with partial shade. The scent of climbing honeysuckle is most often more intense when grown in a sunny and warm spot, such as on a south or west-facing wall. Honeysuckle Varieties For Pots Honeysuckles are widely available in so many different guises and forms. From tall climbers to small shrubs, there is a perfect variety for every garden or balcony. With so many to choose from, here are some great options when growing in pots: Japanese Honeysuckle L. japonica ‘Halliana‘, more widely known as Japanese honeysuckle, is hardy to H5 and is a tall evergreen climber growing to a height of 4-8m and a width of 1 -1.5m. It produces stunning scented flowers from April onwards into the summer, which start out white and slowly turn yellow. Common Honeysuckle L. periclymenum ‘Graham Thomas’, a cultivar of the common honeysuckle or woodbine, is a vigorous and scented deciduous climber that can grow to 4-8m tall and 1-1.5m wide. Reportedly hardy in all of the UK, it should be able to cope with the worst of any British winter. With a long flowering season, it produces red berries come autumn. Delavay Honeysuckle L. similis var delavayi, or Delavay honeysuckle, is a hardy and semi-evergreen shrub that can sprawl to a height of 4-8m and a width of 1-1.5m over time, but is often grown as a climber. Flowering from June to September it produces beautifully scented cream coloured flowers that turn yellow as summer progresses. Winter Honeysuckle L. fragrantissima, or winter honeysuckle is a semi-evergreen shrub that produces delightfully scented white flowers between December and March. This grows to a height of 1.5-2.5m and a width of 1.5-2.5m. It is best planted near a doorway or porch so the scent can be enjoyed as often as possible during the winter. Poor Man’s Box L. nitida, is better known as poor man’s box. A small-leaved evergreen variety that can be small and compact and thus perfect for hedges or topiary. If left to its own devices it can eventually grow to 1.5-2.5m tall and 1.5-2.5m wide. Growing Honeysuckle In Pots It may be true that some honeysuckles don’t do as well in a pot when compared to being planted directly in the ground, but the majority will grow perfectly well. The huge advantage of growing in a pot is that they can be grown on a terrace or balcony and can be moved around to find the best position. With this in mind, in their native habitats, climbing honeysuckles tend to have their roots in the shade and their stems reaching for the sky. Honeysuckles are best planted in spring, as the temperatures begin to rise and they have several months to establish before winter sets in. To plant, half fill the pot or container with compost, place the plant in the pot at the same depth as previously planted and backfill around the plant, firming in gently. Water well, top-up any receded soil as necessary and tie in any shoots to the supports. Choosing Containers When it comes to choosing a pot or container for a honeysuckle plant, it is usually a case of the bigger the better – ideally at least two or three times as big as its current pot. This will allow for the roots to spread wide and deep and encourage the shrub or climber to grow well. Honeysuckles will turn up their feet if subjected to waterlogged soil, so adequate drainage holes are a must so any excess water can freely drain away. Using pot risers or feet may help any excess water drain away, as they lift the pot a few centimetres off the ground. Potted Honeysuckle Care When growing honeysuckle in a pot or container it is important to use a free-draining, rich and good quality compost, such as John Innes no 3, which is recommended for shrubs and climbers. If growing a large honeysuckle shrub or climber then support for the plant to grow upwards is generally required. Supports are best installed at the time of planting so the new young shoots can be trained in. Supports can include wooden trellis, bamboo canes or metal obelisks. Even though some honeysuckles are self-twinning, they will benefit from tying in, especially when first establishing themselves. Watering & Feeding Most honeysuckles will grow best in moist, but free-draining soil and if grown in pots will require regular watering throughout the growing season. Since the nutrients in the pot will need replacing over time, it is recommended to feed annually in spring with a general fertiliser and once again later in the growing season. A good mulch of organic matter in the spring is a good idea as well, as it will help conserve moisture during the hotter months. Pruning Honeysuckle pruning depends on the variety. L. japonica ‘Halliana’ and other climbing honeysuckles fall into pruning group 11 and require any congested stems to be thinned out and overgrown shoots reduced to just above a healthy bud in the spring. Reducing stems by up to two-thirds each spring can help ensure the plant does not out-grow its pot and encourages fresh growth each year which flowers in late spring. If the plant needs renovating, which it may do after several years, the plant can be cut down in spring to 60cm from ground level, from which it will grow again. The shrubby L. fragrantissima, on the other hand, is specified as pruning group 2 and does not necessarily need pruning. However, it can be trimmed to size immediately after flowering in April or May, but no later. Common Problems Honeysuckle Aphid Honeysuckles are generally pest and disease-free – however, they can be susceptible to aphids. Aphids or ‘greenfly’ as they are commonly known, are sap-sucking insects which often leave behind a sticky honeydew substance. It is important to start checking honeysuckle plants for aphids from spring onwards, as if caught early control measures can be taken, before a larger infestation potentially causes damage. Controls can include squishing by hand and encouraging aphids’ predators (including hoverflies, ladybirds and ground beetles) into the nearby area. Organic sprays such as fatty acids and plant oils can prove effective or with severe infestations, contact insecticides may need to be used. However, it is important not to spray plants when in flower as this presents a danger to pollinators. Mildew Honeysuckles can be susceptible to powdery mildew, especially during the summer months. Powdery mildew is caused by fungal spores and can sometimes indicate that the roots of the plant are dry. Increasing air circulation can help prevent powdery mildew from developing, so make sure the plant is not overcrowded by other plants. “During a dry spring when young growth is emerging, it’s important to ensure honeysuckles are kept well watered at the roots, as this is the most effective way to prevent powdery mildew,” shares Master Horticulturist Roy Nicol. If your honeysuckle is affected by mildew it is important to collect and dispose of the affected fallen leaves and flowers, as this will help break the cycle of new spores developing in the following spring. For severe cases, fungicides such as Tebuconazole and Triticonazole have been approved for the control of mildew on ornamental plants, but are only recommended as a last resort and after non-chemical controls have been tried. References 1. The Editors of Encyclopaedia Britannica. (1998d, July 20). Caprifoliaceae. Encyclopedia Britannica. Retrieved March 17, 2023, from https://www.britannica.com/plant/Caprifoliaceae
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Divide Alstroemeria Tubers In 4 Steps To Reduce Overcrowding And Produce New Plants
IN THIS GUIDE Why Divide Alstroemeria? When To Divide Alstroemeria How To Divide Alstroemeria Tubers 1) Lift The Plant From The Soil 2) Prepare the Root Ball 3) Separate The Tubers 4) Replant As Quickly As Possible Planting Considerations Dividing Alstroemeria tubers is an easy garden job. Like other perennials, Alstroemerias can be divided to reduce overcrowding and propagate new plants. Why Divide Alstroemeria? There are two main reasons why you should divide Alstroemerias (and other clump-forming perennial plants). The first reason is to clear space and reduce overcrowding in a bed or border, or to stop a mature plant from outgrowing its container. The second reason is, of course, to propagate your plant, and obtain new plants for your garden. Propagation by division is the easiest way to get new Alstroemeria plants, since these plants are not easy to grow from seed. If you collect your own seeds then the plants you grow may not look the same as their parent. Plants grown from seed will also take several years to flower. When you divide Alstroemeria, you will obtain a number of plants immediately, each of which will be an exact copy of the parent plant. These new plants can also be placed in new containers, or elsewhere in your garden right away. Dividing plants is a great way to make new plants to fill new areas in your garden and to improve existing growing areas. When To Divide Alstroemeria Alstroemerias are best divided in April, though you may also undertake the task in May. While other summer flowering plants can often also be divided in autumn, between September and November, this is not the best time to divide Alstroemeria tubers because they can be a little tender. Also, because the new plants must be planted right away, spring sowing gets them the easiest start. If your Alstroemeria is growing in a bed or border, among other perennial plants, it is best to think about dividing your clumps every 2-3 years or so, even if you are not in need of new plants. This ensures that the plants remain healthy and flowering well, and will also help to prevent overcrowding in the growing area. How To Divide Alstroemeria Tubers A little more care is required when dividing Alstroemeria tubers than is required when dividing many other perennial plants, but it is still a relatively easy job. 1) Lift The Plant From The Soil Alstroemerias have fragile roots and they may not cope well with any damage, so it is very important to be as careful as possible at this stage. Place a garden fork or spade into the soil at some distance from the base of the plant. Then gently lever to raise the plant out slowly, easing it out of the soil (or container as shown in our case). 2) Prepare the Root Ball Now that the root ball is above ground, carefully examine it. Gently knock off excess soil so that you can see the tubers clearly. Again, be very careful not to damage the roots. You will note that the tubers are tangled together into a clump. 3) Separate The Tubers As you examine the root ball, you can now gently begin to disentangle individual tubers from the clump. At this stage, you will have to decide how many new plants you wish to make from this parent plant. Often, you will be able to simply tease the tubers apart by hand. Occasionally, you may wish to use a sharp knife to separate roots that are particularly enmeshed, though this is not usually required. 4) Replant As Quickly As Possible The key thing to remember about Alstroemeria tubers is that, unlike tubers of many other plants, they will not store well. You need to make sure that you replant your divisions as soon as possible, either into containers or a suitable spot in your garden. Colin Skelly advises: “When you are dividing more than one cultivar, make sure that you label your pots straight away.” “Once plants are mixed up there is no way to know which is which until they next flower – by which time it is too late to move them.” Remember, as mentioned above, Alstroemerias require reasonably fertile soil, which is free draining, in a sunny and sheltered spot. If using containers, these should be filled with John Innes No. 2 compost or a homemade equivalent. Planting Considerations Alstroemeria plants should be replanted to the same depth that they were at in the previous location or container. Simply bury the tubers and leave any shoots sticking up above the surface of the soil or growing medium. Divisions of tubers should be planted to a depth of around 15cm. Mulching around the plants with organic matter to add fertility, reduce moisture loss and suppress weeds to a degree can be a good idea. However, make sure that the mulch does not actually touch the base of the plants. The divisions should begin to produce new growth and flowers within 15 weeks. Be patient and do not be tempted to give up on your tubers if you are worried that they are not yet growing. Wait for at least four months before determining that something has gone wrong. Keep the area moist but do not overwater – the tubers can rot in damp soil and prolonged waterlogged conditions. Remember that more watering will be required when growing in containers.
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Are Your Rhododendron Leaves Wilting And Drooping? Horticulturists Explain Why
IN THIS GUIDE 1) Cold Or Windy Weather 2) Broken Stems 3) Water Shortage 4) Waterlogging / Excessive Watering 5) Fungal Infection 6) Vine Weevils Or Other Insect Pests References Rhododendron are typically easy to care for and low maintenance, but there are a range of issues that can cause leaves to start wilting and drooping. In this article, we will explore some of the most common issues which can cause rhododendron leaves to wilt and droop. “In addition to producing every possible flower colour, many rhododendrons are fragrant and have beautiful foliage,” says Katrina Clow, Hon. Secretary of The Scottish Rhododendron Society. “They can become trees or remain diminutive little plants and so can suit many types of garden.” 1) Cold Or Windy Weather Many rhododendron are hardy and can easily make it through the winter in the UK. However, some cultivars may well show signs of stress in cold temperatures, especially in windy weather over the coldest months. They will sometimes simply recover after milder conditions return. If leaves are curling in on themselves this may just be the plant’s natural response to cold, exposed conditions, known as thermotropism.1 Rhododendrons curl leaves inwards so that less of the leaf surface is exposed to drying cold winds. This is the plant’s defence mechanism to prevent too much water evaporating from the leaves. The rhododendron may need water, if conditions have been dry, and you should make sure that you conserve that water by laying an organic mulch around the base of the plant. “We cannot control the weather!” exclaims Katrina. “Moist, humid and mild conditions will help prolong flower life. A late May frost or a sudden gale can destroy all the loveliness of your rhododendrons.” Despite this, if you encounter this issue frequently, you may need to consider replacing your shrub with a more cold-hardy cultivar better suited to your location. 2) Broken Stems If the leaves are wilting and drooping only on one side or a certain portion of the plant, the first thing to check for is broken or damaged stems. Of course, leaves will wilt and droop if water and nutrients cannot pass up the stems to reach them. Katrina recommends foliar feeding your rhododendrons in the growing season to make sure your plants get all the nutrients they need. Physiological damage may have been caused not by a more pernicious issue but simply by storm damage or other extreme weather conditions – especially if your shrub is in an exposed location. Be sure to prune out the damaged section as soon as possible to avoid putting excess strain on the rest of the plant. But note, if water is not reaching the leaves effectively, there can be a range of other reasons for this – which we will cover below. 3) Water Shortage Another common reason that leaves on a rhododendron will wilt and droop is issues relating to water. In dry summer months, you may find that water shortage is the culprit. Rhododendrons have shallow roots and require moist soil. Make sure that you are watering sufficiently, and with sufficient frequency during dry periods. “Spray the foliage with rainwater if required,” Katrina suggests. Remember that smaller cultivars growing in containers will have higher water needs. Moisture is especially critical in the middle of summer to help flower bud production for the following year. A dry summer can seriously hinder flowering. “Large rhododendrons may be more prone to a lack of water in pots,” adds Master Horticulturist Peter Lickorish. “If potting into something larger or planting out is not an option, they can be pruned to help them manage water. “However, as they flower on older stems, pruning must be carried out minimally over several years to avoid a dent in blooming.” 4) Waterlogging / Excessive Watering Wilting and drooping leaves can also unfortunately be a sign that you have watered too much. Rhododendrons do need moist soil, as mentioned above – but they will not do well when the soil or growing medium becomes waterlogged. During heavy rains, soils that do not drain freely may cause a problem for rhododendrons. Make sure that you improve the soil structure with the regular application of organic mulch, which will aid in building a healthy, aerated, moisture-retentive yet free-draining soil. If growing rhododendron in pots or containers, make sure that you have chosen an appropriate moisture-retentive yet free-draining ericaceous mix. Make sure that the container you have chosen is allowing water to drain out the base. 5) Fungal Infection Unfortunately, waterlogged conditions can increase the likelihood of a fungal infection taking hold, and fungal infection could also be the cause of your rhododendron leaves wilting and drooping. Phytophthora Root Rot One of the most common fungal infections is Phytophthora root rot. Spores come in with plants introduced to your garden, or on the wind. Sadly, once you see this problem in the leaves, the disease is likely to be quite advanced in the roots. If you unearth the roots you will likely see much evidence of decay if this is the problem. However, it may be difficult to tell whether prolonged waterlogging alone has caused this issue, or whether fungal disease is present. Honey Fungus Rhododendron may also suffer from honey fungus. This is another fungus that attacks the roots of a number of woody perennial plants. If this fungus is present, this will also cause root death before you are aware of wilting and drooping leaves. If you look at the roots and find a white mycelium (which smells strongly of mushrooms) around the roots and the base of the shrub, this is likely to be the problem. When one of these fungal diseases is present, you should carefully dispose of the plant and replace the topsoil from the root area. Susceptible plants should not be grown in the same area and you should replant with more resistant species. 6) Vine Weevils Or Other Insect Pests Vine weevils and other insect pests can also cause rhododendron leaves to wilt and droop. This can be a problem, especially, for rhododendrons which are grown in containers. Adult vine weevils will nibble the edges of rhododendron leaves, but it is the grubs that pose a more serious problem – they feed on plant roots over the autumn and winter months, causing wilting and eventually death of the plant. You can deal with vine weevils by picking the grubs from the compost or potting soil by hand. This may be time-consuming but try to make sure you remove as many larvae as you can. There are also biological controls available. You can introduce nematodes: Heterorhabditis megidis, H. bacteriophora and Steinernema kraussei are amongst those commonly used. These are usually applied in August or early September, but may also be applied in late spring. If your rhododendron leaves are wilting and drooping, the problem usually relates to water. For some reason, the leaves are not getting the water and nutrients they need. Rule out environmental problems before deciding whether disease or pest species are causing the issue. Working through the list above should usually give you an answer to your question. References 1. Van Zanten, M., Ai, H., & Quint, M. (2021). Plant thermotropism: an underexplored thermal engagement and avoidance strategy. Journal of Experimental Botany. https://doi.org/10.1093/jxb/erab209
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7 Essential Steps For Protecting Plants In Winter That Every Gardener Should Know
IN THIS GUIDE 1) Choose Winter-Hardy Plants 2) Grow In A Greenhouse Or Polytunnel 3) Create A Frost-Free Micro-Climate 4) Cover Plants With Row Covers, Cloches Or Fabric 5) Use Mulches To Protect Plant Roots 6) Use Thermal Mass To Protect Plants From Frost 7) Make A Hotbed To Provide Heat From Below References If you want to enjoy a beautiful and productive garden year-round, considering how to protect plants from winter frosts is important. One of the first things we learn as gardeners is that different plants have different growing needs. And becoming a better gardener means building up a body of knowledge about the environmental needs of different plants. As you grow as a gardener, you will learn which plants can come through the winter months unscathed where you live, and which might need a little help and protection. In this article, we’ll take a look at how to protect plants from frost in winter. 1) Choose Winter-Hardy Plants Before we begin to look at some different solutions to keep plants safe from winter frosts, it is worth mentioning that sometimes, the best solution can be the simplest one. For a successful winter garden, and for a low maintenance scheme that can look great in your garden year after year, it can be a good idea to simply choose plants that can withstand winter temperatures and chilly conditions where you live. There are a wide range of fully hardy plants which will withstand winter in the UK without you needing to take any additional measures at all. When we talk about winter-hardy plants, it is worthwhile mentioning that some will be evergreen, and remain in leaf and look good without being damaged by frosts. Heuchera is highly tolerant of frosty conditions Others will die back over winter, but retain happy and healthy root systems that remain undamaged by frost below the soil in a dormant state, before then bursting into life in the spring. These (usually woody) plants have specially evolved to overwinter as underground storage organs or seeds to hide away during cold periods.1 Choosing the right plants for the right places might mean that you do not need to take any additional measures to protect plants from frost in winter. It is also worth mentioning that if you have a vegetable plot or kitchen garden, exposure to frost can actually be beneficial rather than detrimental for certain crops. Brassicas, members of the cabbage family, parsnips and other root crops, and leeks, for example – will actually taste sweeter and better after they have been exposed to freezing conditions.2 2) Grow In A Greenhouse Or Polytunnel However, there are of course plenty of more tender plants which will benefit from winter protection. Growing undercover in a greenhouse or polytunnel structure is one key way to protect plants from winter frosts. Container plants can be brought inside such a structure during the winter to protect them from the cold (and wet) of winter. And there are a range of vegetables that can be grown in a greenhouse all year-round here in the UK. An unheated greenhouse or polytunnel can often remain frost-free over winter in the UK. Even without additional heating, it can be a very useful addition for home growing. A cold frame can be handy if you don’t have space for a full-sized structure. A cold frame For even more tender or exotic plants, you can also consider heating an undercover growing area to provide even less chilly conditions. “For some half-hardy species, such as succulents like Echeveria and Agave, it can be enough to provide a winter shelter outdoors,” adds RHS Master of Horticulture Colin Skelly. “A sheet of perspex or opaque insulated sheet, for example, supported above the plant/s will provide shelter from the worst winter wet. “It is the combination of cold and wet over time, in UK conditions for example, that can lead to damage. “[Plants] will still need individual protection, such as fleece, in the coldest spells but a shelter should avoid the need to move or heat them.” There are many sustainable ways to do so, including with hot water or ground-source heating, or with solar-powered electric heaters, for example. 3) Create A Frost-Free Micro-Climate A sheltered garden protected from the elements If you do not have space for, or don’t really want a greenhouse or polytunnel, there are other ways to protect plants from frost in winter. Some interesting solutions involve thinking about how you can alter the environmental conditions in your garden to create a more sheltered, warmer, and potentially frost-free micro-climate. Where you place plants can have a bearing on the micro-climate in your garden – especially when you consider larger plants like trees and shrubs. Placing trees and shrubs in the right places can shelter your garden from freezing winds and protect other plants from frost. However, it is also worth noting that to protect plants from frost, it might be helpful to make changes to the existing vegetation, to help alter the micro-climate conditions in beneficial ways. For example, you might open up a tree canopy to the south to let in more sunlight to keep things warmer in winter, or you might create gaps in boundary hedges across a slope, to drain cold air from a frost pocket. A frost pocket is formed by topographical features, trees and other features of the environment. This is an area that is considerably colder than other spots in your garden in winter, gets frosty earliest, and is slowest to warm in spring. Sometimes it is possible to alleviate these frost pockets – sometimes it is simply best to avoid planting anything which may be damaged by frosts in these areas. Simply planting tender plants in a different part of your garden could help protect them from frost in winter. 4) Cover Plants With Row Covers, Cloches Or Fabric Cabbage seedlings Another option to consider is covering beds or individual plants. You can use a range of different row covers, cloches or fabric covers such as horticultural fleece or reclaimed textiles to do so. Often, you can use reclaimed materials to make row covers and cloches that might otherwise have been thrown away. “Wrap up your tenderer plants in fleece,” shares Caroline, one of The 3 Growbags. “There are some good jackets on the market to buy or you can make your own.” Plastic bottles are commonly used to create a ‘greenhouse-like’ effect for plants Using milk containers as small individual cloches is just one simple example. A cane or thin branch through the handle and inserted into the soil will keep these in place. Covering beds can be a good idea in a vegetable garden, since it will provide some winter protection and allow you to make use of your growing areas all year round. Covers can make all the difference for tender plants You might use row covers, for example, to protect winter sowings of overwintering peas or broad beans, root crops, brassicas, or other more hardy leafy greens. You may be surprised by the difference a simple cover can make, and the variety of crops it allows you to overwinter in your garden. Individual ‘hot boxing’ plant covers 5) Use Mulches To Protect Plant Roots Vegetable bed with strawberries and garlic covered with mulch Another thing to remember is that plants do not necessarily have to be covered in their entirety to keep them safe from frost. Often, it is the roots of a plant that require winter protection, not the above-ground portion of the plant. “Take a day out in late Autumn and prepare your plants by dumping a good mulch of dung on your perennials,” says Caroline. As Caroline suggests, to prevent root damage during cold winters, thick carbon-rich organic mulches can help. Simply lay straw, bracken or dried leaves in a thick layer around the base of vulnerable, or shallow-rooted plants to keep them safe from frost in winter. This can be a good strategy, for example, with autumn-sown onions and garlic. Mulching well around these winter crops can ensure that they get off to a good start when spring arrives. 6) Use Thermal Mass To Protect Plants From Frost Using thermal mass for an indoor vegetable garden Whether you are growing outdoors or in a greenhouse or polytunnel, regulating temperature and protecting plants from frost involves an understanding of thermal mass. Thermal mass relates to the capacity of a material to catch and store the sun’s heat energy.3 Materials with high thermal mass like stone, brick, ceramics/clay, earth and water absorb the sun’s heat during the day – then release it slowly when temperatures fall. This is one reason why it can be beneficial to place more tender plants beside a sunny south-facing stone or brick wall. Moving tender container plants close to a thermally massive sunny surface could help keep them safe from frost. Outdoors, you can also protect tender plants by placing a wall with thermal mass around them. You might use stones or bricks as bed edging, for example. You can also build a protective wall around tender plants using bottles or other containers filled with water, which can heat up a little during the day and keep plants a little warmer at night. Adding thermal mass is also a good idea when building a greenhouse or polytunnel. A sunken polytunnel with covering to protect against frost You might, for example, create a sunken greenhouse, or partially earth-sheltered structure, to take advantage of the thermal mass of the soil. You could also build a greenhouse up against a south-facing wall on your home, or even integrate a greenhouse into your home. Clever design of an undercover growing area can help you keep it reliably frost-free without having to resort to any additional heating, even in colder areas. If you already have a greenhouse or polytunnel, you can add additional frost protection by adding thermal mass in edging, pathways or staging. Of course, you can also improve the insulation by adding an extra layer of plastic (or bubble wrap) inside the outer skin. Or simply use some of the other strategies mentioned above for your plants grown undercover as well as those growing outdoors. 7) Make A Hotbed To Provide Heat From Below A hotbed garden structure One final interesting option to consider to protect plants over the winter months is to provide a natural heat source. Rather than introducing additional space heating, you can consider taking advantage of the heat given off by organic materials as they decompose. A hotbed is a raised bed filled with layers of compostable materials (often straw and manure) and topped with a layer of compost or soil. Tender seedlings and other tender plants will love the gentle heat from below. Using a hotbed, especially in conjunction with some form of cover, can help you nurture plants through the winter months unscathed. References 1. Govaerts, R. (n.d.). How did plants evolve frost hardiness? Kew Royal Botanic Gardens. Retrieved March 20, 2023, from https://www.kew.org/read-and-watch/plant-frost-hardiness 2. Voyle, G. (2016, September 20). Can I harvest garden vegetables after a frost? MSU Extension. Retrieved March 20, 2023, from https://www.canr.msu.edu/news/can_i_harvest_garden_vegetables_after_a_frost 3. Reardon, C. (2013). Thermal mass. Your Home. Retrieved March 20, 2023, from https://www.yourhome.gov.au/passive-design/thermal-mass
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Plant A Bulb Lasagne (Layer Them In Stages) For Incredible Mixed Displays
IN THIS GUIDE The Purpose Of A Bulb Lasagne Choosing A Container Choosing Your Growing Medium When To Plant A Bulb Lasagne How To Plant Your Bulbs Aftercare Where To Place A Bulb Lasagne Choosing Plants For A Bulb Lasagne Largest / Latest Flowering Medium Sized / Mid-Flowering Small / Earliest-Flowering Planting a bulb lasagne will help you cook up the recipe for successional blooms in your garden. A ‘bulb lasagne’ is the name sometimes given to layering bulbs, either in a container or in a planter or small raised bed. Largest, latest flowering bulbs go in the deepest layer of your lasagne, with more, earlier flowers above them, up to the earliest flowering bulbs near the top. With two tiers of bulbs, this is sometimes called ‘double-decker’ planting. However, you can sometimes stretch this and have three layers (and occasionally even four). This is a simple gardening job that you can enjoy with children. It is very easy whether you are a complete gardening novice, or someone far more experienced looking to try out some new combinations or varieties of bulbs. The Purpose Of A Bulb Lasagne A mixed container of bulbs with Hyacinths, Narcissus ‘Thalia’ and Tulips Just as layering plants above the ground is a great idea to make the most of your space, so too is layering bulbs below the soil (or potting mix). Layering bulbs in the same container can help you make sure that you make the most of your space and have flowers for visual appeal (and for bees and other pollinators) over as long a period as possible. By layering spring (or summer) bulbs, corms and tubers in pots, you can ensure that the flowers bloom successionally. You can choose your bulbs carefully so that each flower is coming into bloom just as the latter begins to fade. “Growing early tulips and daffodils that are then replaced by frothy summer displays of Gypsophilia and grasses in pots is a great container garden idea,” shares Gardener Elliott Beveridge. Spring bulbs are particularly useful in a garden, because they can often provide early blooms when there are few other flowers around for pollinators. They can also fill in gaps in an ornamental planting scheme before summer flowering plants take over the display. “Never go for a single layer!” advise the experts at BULBi, a UK nursery and supplier of hundreds of bulb varieties. “At the bottom, plant the taller types like tulips, in the middle, plant bulbs like daffodils and hyacinths and, at the top layer, plant smaller varieties like crocus or muscari. “This way, you can enjoy a blooming pot all spring long!” Choosing A Container The size of container required will depend on which bulbs you would like to grow, and also, of course, how much space is available. Typically, however, the larger a container you can manage, the more effective and dramatic the display will be. Spring flowers often look best when grown in clumps or drifts with as many of them as possible. “Bulbs can rot faster in a pot,” the experts at BULBi remind us. “Make sure there is a hole in the bottom so excess water can drain away and fill the pot with hydro grains first, or, if you don’t have that in the house, shards or grit are fine too.” In terms of depth, you need to make sure that you have the space to accommodate the planting depth of the bulbs on your lowest tier, plus at least 10cm below that for their root systems. Typically, a pot or container at least 50cm deep and 30cm wide will be best. Though with some bulbs, you will not need such a sizeable container. Remember, when thinking about containers, that you do not necessarily have to buy containers for the purpose. If you use your imagination, you will soon see that there are a range of reclaimed materials and items that you could reuse in your garden. Choosing Your Growing Medium Bulbs do not require anything particularly fancy when it comes to the growing medium. A general multipurpose compost is usually fine. You can also consider making your own potting mix with ½ homemade compost and ½ garden soil, which should be fine for most spring bulbs. Just make sure that your mix is relatively free-draining, or your bulbs may rot. You can also consider adding other homemade materials like leaf mould to the mix. “It’s advisable to add potting grit, up to one part to four compost, to ensure the mix is free-draining,” shares Master Horticulturist Roy Nicol. “Avoid using a layer of grit at the bottom of the pot which creates a wet sump and prevents the lower layer of compost from draining.” When To Plant A Bulb Lasagne You should sow spring-flowering bulbs in autumn. In September or October, choose your bulbs and get a pot or container ready. One thing to note is that you do not need to leave your container bare with just bulbs under the soil during the winter months – you can consider adding winter bedding plants (like pansies, for example) to the top of the containers until the first bulbs begin to emerge in late winter or early spring. How To Plant Your Bulbs 1) Prepare Your Container Prepare your pot, container or planting hole. Place a single crock at the base of a container to cover the drainage hole and prevent compost washing out. Add a peat-free multipurpose compost mixed with potting grit to your container (make sure there are at least 10cm of potting mix below the first layer of bulbs for their roots to grow into). 2) Place Your First Layer Place your first layer of bulbs, each around bulb width apart and facing upwards. Try to identify the top and root end of each bulb. Typically the top of a bulb is pointed and the bottom (the basal plate) is flat with evidence of old roots. With some bulb types this can be challenging, however, so if you are not sure, place them on their sides and they should still grow upwards towards the light. 3) Cover And Layer Bulbs Cover these first bulbs with a thin layer of compost then place your second tier of bulbs. Try not to place the bulbs in this layer immediately above the ones below. Use a different layout pattern for each tier if possible. For example: You might plant a ring of allium bulbs. Then place daffodil bulbs in the centre of this ring for the second layer. Then add crocus around the edges of the pot. The crocus will flower first, then the daffodils, then the alliums just as these begin to fade, giving a longer-lasting display. “Even if bulbs are planted directly on top of each other, the emerging shoots from lower bulbs will find a route past bulbs above, so positioning is not critically important,” adds Roy. 4) Repeat Your Layering Repeat this stage if you are adding a third and perhaps fourth layer. Note that, as a general rule of thumb, you should aim to add your layers so that each bulb is planted at around 3 times its own height in depth. However, to ensure adequate spacing, lower-level bulbs may be planted deeper than this. So start your first tier at the right depth below the finished soil surface for the bulbs you have chosen. Make sure, also, that you layer the bulbs in the order in which they are to flower. Bury the top layer of bulbs with around 10cm of soil. Add overwintering bedding plants to the pot to make use of it over winter while bulbs are still not throwing up shoots. Aftercare As you can see from the above, it is very easy to create a bulb lasagne, you just have to bear a few simple things in mind. Make sure you keep your container moist but not soggy throughout the flowering period. Take care not to overwater, especially over winter, or rot could set in, and keep your eyes peeled for pests. “If a particularly wet period is encountered over the winter, it’s worthwhile either covering the pots or moving them under cover to prevent the bulbs from sitting in wet compost for an extended period,” shares Roy. “In early spring, they can be moved into position ready for their display.” A well-planned and not overly crowded scheme may continue to flower well in your container for two or three years, after which you will likely have to extricate your bulbs, thin them, and re-pot them in new containers. “It’s worth remembering that while many bulbs such as Daffodils & other Narcissus are perennial, most Tulips split into smaller bulbs after flowering and the display in subsequent years is not as good,” warns Roy. “I have found this is especially the case with the showy Tulips with large double or frilly flowers. “In my experience, some of the Tulips which are reliably perennial year after year are ‘Ballerina’, ‘Triumphator’ and ‘Spring Green’. “It’s also worth considering species Tulips such as Tulipa clusiana, Tulipa sylvestris and Tulipa sprengeri. If you are adding bedding plants to a container of layered bulbs, be sure to replace the top layer of compost each time you change out the bedding specimens. Where To Place A Bulb Lasagne A bulb garden is usually made in a large plant pot – the larger the pot, the greater the impact can be. But it is worthwhile considering that you could also layer bulbs in a planter or raised bed in a small garden. When choosing where to position your pot or create your bulb lasagne, it is important to think about which bulbs you will be growing (or the space available). Be sure to consider sunlight, shade and other environmental factors such as whether the soil is likely to drain well over the winter or stay consistently wet. Many spring bulbs prefer a sunny spot, but there are also bulbs suitable for more shady conditions. Choosing Plants For A Bulb Lasagne When choosing bulbs for layered planting, the first thing to think about is where they are to grow and the environmental conditions to be found there. Once you have considered the basics, you need to decide which bulbs you would like to grow. There are a number of factors which might enter into your decision. For instance, flower shape, colour and size. But one of the most important things to consider is when each of the bulbs you are considering will flower. Remember, the goal is to find different bulbs, and to plant them in layers in the same space so that they will bloom over as long a period as possible. Largest / Latest Flowering Largest, latest flowering bulbs for a bulb lasagne include: Alliums Lilies Tulips Medium Sized / Mid-Flowering Medium-sized bulbs to be planted above those might include: Daffodils & Other Narcissus Earlier Tulips Hyacinths Small / Earliest-Flowering Small, early bulbs to plant closer to the top of the soil or potting mix include: Anemones Crocus Glory of The Snow (Chionodoxa) Grape Hyacinths Miniature Irises Snowdrops Though spring-flowering bulbs are most commonly used for a bulb lasagne, you can also consider planting summer flowering bulbs, corms like gladioli or dahlia tubers, for example. A basket of bulbs ready for planting As you can see from the above, layering the bulbs correctly is the main trick to success in creating a bulb lasagne. As long as you get this right, you should be pleased with your displays. Play around with different spring-flowering bulbs to work out the perfect combinations, and have some fun thinking about new combinations of bulbs to try.
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