Growing
Bearded Iris Growing Tips From Award-Winning Grower Simon Dodsworth
IN THIS GUIDE Overview How To Grow Bearded Iris Bearded Iris Care Pruning & Deadheading Common Problems References One of those flowering plants that needs no introduction, Iris includes among its categories a type that is a garden classic and favourite: Bearded Iris. This rhizomatous plant is remarkably fuss-free about soil, watering or anything else – though it is important to get the basics right. The plant bears breathtakingly beautiful blooms that have a vertical orientation and come in an astonishing range of hues, with many cultivars producing even multi-coloured, patterned flowers. Across our Iris guides, you’ll notice we have sought advice from Simon Dodsworth, the Founder of The English Iris Company. “Tall Bearded Irises are spectacular flowers and really can help lift the spirits,” says Simon. “They are also easy to grow and bulk up well and, with a little TLC, will last for years and years.” Overview Botanical Name Iris germanica Common Name(s) Bearded Iris Plant Type Bulbs / Perennial Native Area Mediterranean Hardiness Rating H6 Foliage Upright and evergreen Flowers Upright and dropping petals. Fragrant, showy flowers Flowering Months May, June The Iris genus is classified under Family Iridaceae.1 This family is one of those that takes pride of place among the families of flowering plants because it includes – besides Iris – crocus, gladiolus, freesi, and even more flowering plants. Like Irises, many of these other genera include herbaceous perennials. Similar to those genera, Iris bears long strap-like or sword-shaped leaves of a sea-green or bright green hue, sometimes with a bluish tinge. These leaves grow in a ‘fanned-out’ arrangement. Iris species occur almost throughout Asia, Europe, and North America.2 How To Grow Bearded Iris Bearded Irises by themselves, let alone other types of Irises, offer such a wealth of diversity in plant size, flower size, and floral colour (and also blooming season and fragrance) that you can grow them pretty much “wherever you please” – though there are some non-negotiables for healthy plants. “Importantly, irises flower at a key time in the gardening calendar and fill the gap left between the last of the spring bulbs and the first species of roses,” explains Simon. “For this reason, they merit a place in all our gardens.” Where you can or should plant Iris is limited only by your imagination. A mass planting of mixed bearded Iris in a good-sized bed will provide a truly breathtaking vista of floral form with fantastic colour. They are excellent choices for a mixed bed too provided you pick the right companion plants. As general guidelines, the taller varieties with their large flowers are very suitable for the rears of beds while the shorter ones are perfect for courtyard gardens. Intermediate-height Irises are usually perfect as companion plants – intermediate and dwarf varieties are also great for borders. Reserve the visually stunning ones such as the taller varieties with near-black, high contrast, and vivid ‘self’ – so to speak – flowers as specimen plants to be planted in containers and set by the doorway or on the veranda or the patio. It must be said that Bearded Iris is that rare plant that is almost as at home in a formal garden as it is in a cottage garden, thanks to the geometric leaf shapes. Planting Rhizomes Bearded Irises are most commonly – and very easily – grown from rhizomes. Though it can be an exercise in pampering and frustration to grow Iris from seed, there’s absolutely nothing to growing Irises from rhizomes. Rhizomes can be planted after they have started to sprout leaves and even push up flower stalks. The advantage in doing so is that a beginner can easily tell which way to plant the rhizome in a bed by simply ensuring that the leaf fan is directed away and outside from other Irises or rhizomes with each one’s ‘nose’ being directed inwards, or place the rhizome such that all are oriented in the same direction. When choosing a spot to plant your iris rhizomes, Simon recommends a hot and sunny place in your garden – “the hotter, the better.” He also highlights the importance of planting your rhizomes in a growing medium that drains well. “Make sure your soil is free draining. Bearded Irises are susceptible to rhizome rot and the best way to avoid this is to plant your irises in a good gritty mix. “Irises will do well in clay soil but, again, it is essential to add a peat-free compost and lots of pea shingle. “If the land is heavy, add a layer of brick rubble and coarse gravel to the base of the bed.” Mid to late summer is the perfect season for planting rhizomatous Iris: First, loosen the soil down to 30-35cm and enrich or amend as required. Make a shallow planting hole within which form low, loosely-packed mounds or ridges where you intend to plant the rhizomes. Place a rhizome on the mound or ridge, and carefully spread out its roots evenly. Water very moderately and fill in the hole without packing in the soil such that the upper part of the rhizome to about a good centimetre stays open and exposed. This is to ensure your iris blooms the following year, Simon explains. Continue planting other rhizomes similarly. “Plant your irises 23-30cm apart in groups of three per variety, with 46cm spacing between each group,” advises Simon. “Choose a mix of varieties that extend the bloom period, with a selection of early, mid and late flowering varieties.” The closer the rhizomes, the more spectacular the visual impact but you will need to separate and divide the rhizomes within a couple of years. The further apart the rhizomes are, the greater the number of years you can leave them be to naturalise but you will have obvious gaps between the plants. 30cm is a smart compromise. Now give the area of planting a good soaking and firm up the soil on the sides of the rhizomes (but not above them) so that rhizomes and plants are held in place. Bearded Iris Care Irises should be planted in full sun. Leaving aside the plant, Iris rhizomes need sun and also good air circulation, as Master Horticulturist Peter Lickorish explains: “The need for sun to reach the rhizomes cannot really be overstated, in my opinion. “Because of this, planting in a dense, mixed border can be challenging, so I find planting in a bulb border of mixed bulbs for different seasons can work well. “Iris rhizomes, along with many bulbs including tulips, require similar free-draining conditions and because bulb foliage is only seasonal, it does not cast dense, long-lasting shade over rhizomes. “To look extra neat when planting many rhizomes, find the north end of the bed and plant the rhizomes so their tips are facing this end, so each rhizome bakes on the south-facing side. “I find they look very satisfying when they all face the same way.” Soil Requirements A fertile, clay-free loam enriched with humus or compost is ideal for Irises. No matter what the soil, it must drain very well – it is preferable for the soil to have some gravel or similar amendment that will assist in drainage. Soil pH a notch or two from 7.0 is perfect though anything from Slightly Acidic to Slightly Alkaline is fine. Watering & Feeding Rhizomatous Irises are a little too often made out to be water-guzzling plants but in reality, in most areas of the UK, they will need only moderate or supplemental watering. Use a bone meal feed when you plant or opt for a seaweed feed if foxes are a problem, says Simon. “Feed them in spring and autumn.” Avoid feeding Irises with nitrogenous fertiliser. An organic or liquid 5-10-10 or plain organic compost are ideal for Irises. Dividing On a periodic basis, as and when necessary, the clumped-up rhizomes will need to be divided. With the rhizomes visible at the soil surface, you will know when the rhizomes have become dense it’s time to get down to business; however, every four years is a good rule of thumb. The end of summer is the right time for dividing rhizomes. Do not divide rhizomes when the soil and rhizomes are wet or damp. First, remove the soil from around the rhizomes. Be sure to carefully loosen a rhizome’s roots and gently lift them, and (only) then pick up the rhizome. You will be able to see a narrower collar-like ‘join’ at an angle on most rhizomes. Simply break or pull apart the rhizome at this ‘join’. Large and long rhizomes may be divided with a sharp, sterilised knife. Pruning & Deadheading Spent flowers should be deadheaded. In particular, be watchful for seed pods lest your garden gets seeded with Iris plants that will remain unproductive for a good few years. “Do not cut back the flowering spike after flowering,” says Simon. “Allow it to die back naturally, then break it softly by placing your thumb at the base of the flowering spice and push until you hear a ‘crack’! “This ensures a smooth break at the base of the plant and prevents ingress of water down a cut flower spike.” You should not cut back the foliage at this time as the leaves will continue to photosynthesise through autumn, to generate energy which is shipped back to the rhizome for the following year’s blooms. However, you can certainly trim unsightly tips and tatty leaves. “Good plant hygiene is essential before the onset of winter,” explains Simon. “In late Autumn or when the leaves have stopped growing, remove all old leaves from the base of the rhizome. “Then, I’d recommend that you trim the leaves back into a fan shape 10-15cm tall and cut back any old or rotten rhizomes.” As Simon suggests, as soon as the leaves have withered and browned they should be cut back. Common Problems “Irises are drought-tolerant and resistant to most pests and diseases, but in late autumn, check for slugs,” Simon says. “Small black varieties are particularly troublesome. Apply non-toxic pellet ‘Ferrimax’ or an appropriate equivalent if present.” Iris borers and soft rot are the two other serious problems that can afflict this rhizomatous plant, though this is not usually an issue here in the UK. Soft Rot Soft rot is caused by a bacteria which infects Iris rhizomes under favourable conditions of climatic warmth and dampness. If some rhizome exudes a foul, rotting smell and is soft to the touch, it is almost surely soft rot. Other symptoms are the central leaves first yellowing and wilting, signs of decay at their bases, and then the whole fan withering. To address the problem, do as follows on a sunny, dry morning. Cut off the affected part of the rhizome and a little more besides with a sharp, sterilised knife such that the remaining rhizome displays healthy tissue and does not have any foul smell. If the affected part is too large, the entire rhizome will have to be removed. Also scoop up all the nearby soil. Lightly coat the newly-cut surface and edges with garden sulphur (and put some in the surrounding soil) and leave the rhizome exposed to the sun for the entire day. Other than these two critical problems, Irises may be affected by a less serious problem namely aphids, and those garden nuisances, slugs and snails. References 1. Iris x germanica. (n.d.). North Carolina Plant Toolbox. Retrieved March 13, 2023, from https://plants.ces.ncsu.edu/plants/iris-x-germanica/ 2. Iris × germanica. (n.d.). Kew Royal Botanic Gardens. Retrieved March 13, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:438637-1
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Growing Camassia From Bulbs: Get That Summer Prairie Look In Your Garden
IN THIS GUIDE Overview How To Grow Camassia Plant Care Pruning Buying Camassia References Six-tepalled, star-like blooms in dense flower-laden racemes on erect stalks in pastel tones and deep shades of purples will adorn your garden if you plant a few Camassias. This very reliable, virtually no-care perennial bulb plugs that spring-to-summer transition season. It hails from the sunny prairies and moist meadows of the United States where it paints the landscape in big, broad blazes of colour.1 Camassia is a long-lived deciduous perennial that has probably flown under the radar of a goodly number of gardeners. This easy-grow and very well-behaved bulb will keep coming up year after year and naturalise in your garden, but ever so gradually and ‘tactfully’. You don’t have to worry about Camassia pulling a no-show, and you don’t have to worry about Camassia taking over your garden. Overview Botanical Name Camassia Common Name(s) Camas, Quamash, Wild Hyacinth, Camosh Plant Type Perennial Bulb Native Area Western North America Hardiness Rating H4 Foliage Deciduous; Grass-like Flowers Six-tepalled, star-shaped blossoms When To Sow September, October Flowering Months May, June Camassia, also called Camass Lily, actually originally used to be classified with Lilies in Family Liliaceae.2 After the usual Botanical shuffles and reshuffles, Camassia’s lot fell with Asparagus in Family Asparagaceae!3 And this factoid brings us to a third name for this plant – in most parts of the United States it still goes by what the pioneers called it: Camas, a phonetic simplification of the Native American name. Camassia includes all of six species and a handful of cultivars. While the species range quite widely in height, running from only about 30 centimetres all the way to 1.3 metres, all varieties – species and cultivars – have similar foliage which comprises of clumps of narrow linear leaves. This bulb starts blooming after Tulips have displayed their charms and shut up shop. Camassias light up gardens and meadows between Flowerdom’s two peak seasons, producing blooms through May and moving into June. C. leichtlinii Colours include creamy white, and shades of blue and purple from the palest lilac through to the deepest violet. The bright, sunny yellow stamens make a striking contrast on the flowers that are in brilliant hues of purple and violet. How To Grow Camassia Like most bulbous plants, the straightforward way to grow Camassia is through bulbs. It is possible to grow them from seed but that method is not a very easy way to propagate what is an easy-care plant. Also, seed-grown Camassias bloom after at least three years and even more. You should choose bulbs that are large, evenly shaped, firm to the touch, and do not show any nicks or any loss of the bark-like covering or skin. Where To Plant First off, though Camassia can be planted in containers they do not do as well as they do in open ground for various reasons. Visually too, a Camassia will look awkward in a container; furthermore, it cannot offer anything at all in autumn and winter. Camassias in bloom make a huge visual impact when they cover a sizeable area of land and, therefore, mass plantings are a great way to go. Try planting at least 15 bulbs in irregular drifts – Camassia flowers will look especially lovely on verges and slopes. They can be mixed in with other bulbs such that their respective blooming seasons segue from one to the other so that you can enjoy flowers on the same patch of land from earliest spring to the end of summer. Otherwise mix them up with spring wildflowers with which Camassias’ simple blooms will mingle well. These flowers can be utilised to create a wildflower meadow effect, as Horticultural Consultant Colin Skelly shares: “I like to plant Camassia bulbs in damp meadow gardens, filling a gap between spring and later summer flowering bulbs and perennials.” This well-behaved bulb is not remotely invasive yet naturalises wonderfully well; as such, it will give pleasure for many years and also keep springing a surprise now and again. Finally, this moisture-loving plant will do very well beside a stream or pond as long as the soil is not overly damp in autumn and winter. How To Plant Bulbs are best planted in the September through November timeframe. Water the soil moderately before digging holes. The planting depth should be two to three times the length of the bulbs. Bulbs should be spaced at least 10 centimetres, and up to 20 centimetres, apart. The pointed tip should be upwards. After filling up the hole, do not pack the soil but give the ground a good watering so that the soil is firmed up. Plant Care You don’t have to maintain these plants in any way; all you need to do is ensure the soil does not dry out during the growing season – keep it consistently moist. Indeed, one might say that Camassias thrive on neglect and moisture! Soil Requirements Though almost any soil will do for this sporting bulb, a fertile loam amended with humus is ideal. As a ‘moisture-loving’ bulbous plant Camassia does not object to damp or heavy soils in spring and summer. But when the bulb is dormant in autumn and winter, waterlogged soil can prove fatal; therefore, soil should be well drained. However, the plant prefers moist soil. As for soil pH, here too Camassia is unfussy but anything from Slightly Acidic to Slightly Alkaline will be just right. Preferred Aspect A location where the plants get full sun, or full sun in the morning and filtered or dappled sun in the afternoon is best – partial shade will do. Mulching & Feeding Fertilising is strictly optional. C. leichtlinii ‘Alba’ Every couple of years the soil may be amended with some humus or a light sprinkling of bone meal may be worked into the soil though it must not be allowed to make contact with the bulb or stem. If you anticipate a hard frost in winter, apply a good layer of mulch. Pruning Cut back stalks after the flowers are spent. Allow the leaves to yellow and do not prune or cut back as the foliage synthesises energy to replenish the bulb. It is this store of energy that sets up the bulb to push up stalks and to produce flowers the following year. Leaves should be cut back only after they have turned brown and withered. As a rule, Camassia bulbs should not be disturbed. However, if you have decided to separate and divide offsets, this can be done end of autumn to early winter when the bulb is dormant but before winter chill sets in. One of the big positives of Camassias is that they are not known to suffer from any particular pests or diseases. Buying Camassia ‘Blue Melody’ A large selection of these plants may well not be available at your neighbourhood nursery but a few of the popular varieties will likely be on display. Both potted plants and bulbs are usually in stock at several, though not very many, online stores. Buying bulbs is the better option. If you can find a merchant that sells a mix of 20 to 30 bulbs of several different varieties, then that would be a great buy. References 1. Camassia. (n.d.). North Carolina Extension Gardener Plant Toolbox. Retrieved March 13, 2023, from https://plants.ces.ncsu.edu/plants/camassia/ 2. Camassia scilloides (Wild Hyacinth) Liliaceae. (n.d.). Lake Forest College. Retrieved March 13, 2023, from https://www.lakeforest.edu/academics/majors-and-minors/environmental-studies/camassia-scilloidesand160(wild-hyacinth)-liliaceae 3. Camassia. (n.d.-b). Pacific Bulb Society. Retrieved March 13, 2023, from https://www.pacificbulbsociety.org/pbswiki/index.php/Camassia
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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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Dianthus: All You Need To Know When Growing Carnations Or Garden Pinks
IN THIS GUIDE Overview Carnations Garden Pinks Habitat & Growing Conditions Planting Dianthus Plant Care & Growing Tips Common Problems Sourcing Dianthus References Dianthus, the ‘Flower of the Gods’, was as admired in Ancient Greece as it is in Modern England, and for good reasons. The double, ruffled blooms with their fringed or frilly edges are unique, and exhibit colours from palest pink to maroon-black. Reputed as ideally suited for cottage gardens, it is fair to ask whether this wonderful genus is not ideally suited for any garden. Overview Botanical Name Dianthus Common Name(s) Carnation, Pinks, Sweet William Plant Type Perennial (some annuals) Native Area Southern Europe Hardiness Rating H6 / H7 Foliage Evergreen or deciduous Flowers Showy, often fragrant flowers When To Sow March, April, May, June, July, August, September, October Flowering Months May, June, July, August, September, October When To Prune October, November Dianthus is quite a fascinating genus of flowering herbaceous plants: though it encompasses a fair number of species totalling around 380, much of the ‘press’ and interest surrounds only three of those species – and those three species include untold thousands of cultivars.1 These three garden favourites are D. caryophyllus commonly known as Carnations, D. plumarius, colloquially called Garden Pinks, and D. barbatus, usually termed Sweet Williams. D. chinensis The vast majority of cultivars of interest are evergreen perennials. The ruffly, frilly flowers come in white, yellow, pink, red, and mauve in a remarkable range of hues from palest pastel to rich and intense. Moreover, many cultivars’ flowers are bicoloured, exhibiting feathering, edging, or flecks. They are marked by a somewhat unusual feature: the distal end of most varieties’ petals are fringed, serrated or even toothed. D. caryophyllus All carnations have double or semi-double flowers and most garden pinks are double while a few are single. Another quirky attribute carnations and garden pinks, particularly the latter, have is their scent. While some are unscented, and others are moderately scented, many exude a thick, sweet fragrance redolent of cloves or cinnamon. Carnations Carnations are divided into perpetual flowering or exhibition carnations, border carnations, and pot carnations. The former bloom year-round and are cultivated in greenhouses for exhibiting and floriculture. The latter are compact evergreens to about 25cm and often have semi-double flowers. Border carnations are the ones with which most of us are familiar; these have a bushy, erect habit, are 50cm or more, and have full double flowers. These plants are also typed by the size of their bloom and by whether there is a single flower or a spray. Though all Dianthus cultivars provide excellent cut flowers, carnations are much valued by florists as they stay ‘fresher than a daisy’ in bouquets and are remarkably long-lasting in vases. Garden Pinks D. plumarius Yet between carnations, sweet williams, and garden pinks, it is the last-named that runs away with the popularity prize – garden pinks are British gardeners’ favourite Dianthus. Like carnations, pinks are also divided into types, but they descend from different species. Besides garden pinks, there are cheddar pinks and China pinks; the former are cultivars of D. gratianopolitanus, and the latter of D. chinensis. Pinks are named as such because their petals look as if they were cut by a tailor’s decorative pinking scissors which leaves a zig-zag edge. Habitat & Growing Conditions D. plumarius Dianthus species occur in nature in extensive geographical regions and climatic zones. They are found in the heat of India and Northern Africa to the northernmost reaches of Russia. They grow in fields, woodlands, steppes, hillsides, and taiga. The various species’ hardiness varies from Hardiness Zones Sub-H7 to H3. Nearly all the popular cultivars are hardy to H6. Perpetual flowering carnations are not hardy being suitable only to H2, which is why they are grown in greenhouses. D. ‘Zenit’ The varieties’ heat tolerance varies too. In general, various pinks and sweet Williams are more heat tolerant than carnations. D. caryophyllus, a carnation, originates from the Mediterranean region including Italy and Greece. Though D. plumarius, garden pink, is native to Central Europe, it has colonised several regions of the United States where it is classified as an invasive species. D. barbatus, sweet William, is from Southern Europe, growing in nature in a belt of land from Spain to Hungary and Romania. It exhibits a preference for hillsides and hilly areas. Planting Dianthus The heights, habits, blooms, and colours of Dianthus varieties make these evergreens excellent choices for all purposes from edging a walkway to the middle rows in a mixed bed. Dwarf pinks which grow to 20-30cm are ideal for rock gardens and edging. Pink ‘Pixie Star’ and pink ‘Dainty Dame’ are excellent examples. Mat-forming cheddar pinks are just as excellent for such purposes. These types of dwarf evergreens are also top choices for groundcover. Border carnations attain heights from 50-75cm. Though, in general, they have a bushy habit, they can be pruned for a more columnar form. If this is done many cultivars will require staking, while some require staking anyway. They are perfect for the middle of a bed or even the rear of a narrow bed. Some varieties offer the height, habit and striking bloom to be set out in pots. Carnation ‘Leon Tautz’ and carnation ‘Jean Knight,’ among a few others, make fantastic specimen plants. Midway between the two are garden pinks with a mounding habit and sweet Williams. With heights falling between 30-60cm, they are great for the front of beds and borders, and also are very well suited as pot plants and container plants. Examples include pink ‘Pinball Wizard,’ pink ‘Rhian’s Choice’ and sweet William ‘Auricula-Eyed Mixed’. Plant Care & Growing Tips Considering that the Dianthus genus is quite large and, especially, the fact that a few species have been heavily cultivated for centuries, Dianthus plants respond very well to a single set of generalised gardening tips. Soil Requirements A light, clay-free, sandy, gravelly loam amended with peat moss or compost is ideal for these plants. The soil must be very well-drained. Its pH should be moderately alkaline to slightly alkaline – 8.4 to 7.4. Aspect Plants may get full sun, or morning sun and filtered or dappled afternoon sun. When transplanting, the soil level of each plant should be the same as it was in the tray or pot. Better a little too low than a little too high. As for the spacing, this will depend on the habit and the spread of the variety in question. Staking Some carnation cultivars need support as they grow. Stake them by enclosing the main stem with support canes and tying them around with twine. Pruning In order to encourage a bushy habit or mounding in young pinks, the leader is sometimes bent or pinched, and initial flowering is otherwise impeded until the plant develops a sufficient number of side shoots. Disbudding is a method sometimes used in carnations though this is done to primarily influence targeted flowers and not the plant as a whole. To maximise the size and quality of pre-selected carnation buds for blooming, you may choose to disbud others. “Most Dianthus will make great cut flowers, just cut them and place them in a small vase,” says Master Horticulturist Peter Lickorish. Sometimes, you may find they start to root in the water, so I would then trim off the flower and pot it up to grow on.” Common Problems Dianthus, more often carnations, can be affected by carnation rust, bacterial wilt, and fusarium wilt. They are also subject to viral infections which cause carnation mottle, carnation etched ring, carnation ring spot and other diseases. These each require specialised treatment. Sourcing Dianthus Carnation, garden pink, and sweet William varieties are among the easiest plants to find, with the perennial British favourite garden pink leading the pack. Some or other varieties are available as potted plants in virtually every nursery and garden centre, while seed packets are equally easy to find. In addition, you can get new Dianthus by layering and cuttings. The somewhat more technical art of layering is usually used with carnations while softwood cuttings work well with both carnations and garden pinks. References 1. Fassou, G., Korotkova, N., Nersesyan, A., Koch, M. A., Dimopoulos, P., & Borsch, T. (2022, May 23). Taxonomy of Dianthus (Caryophyllaceae) – overall phylogenetic relationships and assessment of species diversity based on a first comprehensive checklist of the genus. PhytoKeys; Pensoft Publishers. https://doi.org/10.3897/phytokeys.196.77940
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Prevent Blackfly On Broad Bean Plants With Predatory Insects And Trap Crops
IN THIS GUIDE Preventative Methods 1) Keep Blackfly Numbers Down 2) Keep Your Broad Beans Healthy 3) Distract Blackfly With Trap Crops Proactive Removal Methods References Blackfly are sap-sucking insects which can sometimes become a problem on broad bean plants. However, by using the right approaches in your organic garden, you can easily prevent blackfly infestations from occurring and easily deal with blackfly infestations if they do arise. There is no need to resort to extreme and non-environmentally friendly solutions. A few simple steps should help you avoid any issues with your broad beans, and make sure you still get a good crop. Blackfly on broad beans Preventative Methods First things first, in an organic garden, it is always better to deal with potential problems not when, but before they happen. So the first phase in dealing with blackfly on broad bean plants is to make sure that the blackfly population in your garden is not out of control. It is also important to make sure that your broad bean plants are as healthy as they can be – since healthy plants are far less likely to succumb to any pest problems. 1) Keep Blackfly Numbers Down In an organic garden, pest management mostly involves making sure that no one species gets out of control, and that the whole ecosystem remains in balance. Keeping blackfly numbers down means thinking about their natural predators. By attracting plenty of natural blackfly predators, such as ladybirds and lacewings to our gardens, we can keep their populations in check. Companion planting to attract ladybirds and lacewings is the key strategy that can be adopted in an organic garden. Close to your broad beans, you should plant companion crops that draw in these predatory insects. Some great examples of companion crops for broad beans which can achieve this are yarrow, tansy, dill, alyssum, oregano and thyme, though there are plenty of other companion plants to consider. Generally speaking, the more biodiversity there is in your garden, the less likely it is that populations of pests like blackfly will get out of control. Ladybirds are natural predators of the blackfly 2) Keep Your Broad Beans Healthy If your garden is diversely planted and you have already given some thought to pest control, another key thing to consider is the health of your broad beans. The health of your plants, of course, begins with the health of your soil. But with broad beans (a nitrogen-fixing plant) adding too much fertility can be counterproductive and may actually decrease the health and vigour of your plants.1 Over-fertilised broad beans may sometimes be more likely to encounter a pest problem. Water is another key area to look into; broad beans which are not provided with enough water (or which are given too much) will not be as healthy. Broad beans, even dwarf cultivars, also need support – those without adequate support may not be as strong, and are more likely to be infested by blackfly or other pests. Another final thing to remember is that the young tip growth of the broad beans is the most enticing to blackfly. Once your broad beans have sufficient flowers, and the first pods begin to form, pinch off the growing tip. This will encourage the broad beans to put their energy into pod and bean formation – but will also reduce the chances of a blackfly infestation. Incidentally, you should note that the tips from your broad beans can be cooked and eaten as a fresh spring green vegetable, so do not just discard them or add them to your compost heap. 3) Distract Blackfly With Trap Crops Blackfly on nasturtiums Of course, even with natural predation, there will often still be blackfly in your garden. It is important to remember that they are not the enemy. Like all other garden pests, they are also part of the garden ecosystem. And like all other garden wildlife, they too have their roles to play. It is important to remember that we do want some blackfly and other sap-suckers around. Aside from anything else, if we do not have them around, then we do not have the beneficial wildlife which preys on them. When we eliminate pests entirely, therefore, we risk making a rod for our own backs. “Every year black fly populations thrive on my broad beans,” shares Colin Skelly, a Master of Horticulture. “If they get really populous, I might give them a blast with water, but they’re soon back. “They don’t seem to detrimentally impact the overall health of the plant and the crop, so I’ve learnt to live with them rather than fight them.” When blackfly inevitably return to a garden that has been cleansed of them, their populations can grow exponentially, when predatory species are absent. Rather than getting rid of blackfly, therefore, our strategy should not be to keep them away altogether. Instead, it should be to keep them away as much as possible from our broad beans and other culinary crops. In an organic garden, we can achieve this by planting trap crops; this is another type of companion planting that should be used as part of your companion planting strategy. Trap crops are plants which are chosen because they attract blackfly more than broad beans. Placing these in another part of the garden can keep the pests distracted and make it less likely that your broad beans will have a serious infestation. One common trap crop to use for blackfly to keep them off your broad beans is nasturtiums. Blackfly and other aphids seem (at least anecdotally) to be drawn to the nasturtiums more than to beans. You may also see ants herding these insects onto such trap crops. The growth of the nasturtiums themselves may be affected – but your main crops will remain safe. Proactive Removal Methods If you take the steps mentioned above to make sure your garden ecosystem is in balance, your broad beans are healthy, and blackfly are distracted by other plants, then you should find that you encounter fewer serious infestations on your beans. But if you do see blackfly on your broad beans, you should: Try to remove them by hand, or with a jet of water from a hose. Consider introducing predatory species (to make up for a lack of these in your garden). Introducing native ladybird larvae, for example, is one strategy to consider where companion planting has not successfully distracted the insects. However, remember that introducing species is always a last resort, and you should make sure that those you choose were not wild harvested. It is always better to work on naturally attracting wildlife through diverse planting. Pesticides, even organic ones, should be considered as the nuclear option. These will often target species which are not pests, as well as blackfly and other aphids which sometimes are. Killing pest species in your garden is rarely the best option, since this will also have an impact on their predators, and have a knock-on impact on the garden ecosystem. References 1. Biological Nitrogen Fixation. (n.d.). The Nature Education. Retrieved March 13, 2023, from https://www.nature.com/scitable/knowledge/library/biological-nitrogen-fixation-23570419/
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Here Are 8 Resourceful Ways You Can Use Wood Chips In The Garden
IN THIS GUIDE 1) Using Wood Chips As Mulch Nitrogen Sequestration 2) Composting Wood Chips 3) Using Them To Make New Growing Areas 4) Using Chips To Make Biochar 5) Growing Mushrooms 6) Using Wood Chips For Pathways 7) For Ground Cover In Recreational Areas 8) Creating Habitats For Wildlife With Wood Chips References Wood chips can be very useful in your garden – and there are many ways to use them. One important thing to note is that wood chips from different trees, and wood chips of different sizes, can have very different characteristics and those characteristics will determine how best they are used. Are you purchasing wood chip to use in your garden, or are you shredding material from your own garden? The latter option is generally the more sustainable choice. Investing in a garden shredder or wood chipper is a great idea, because it will allow you to avoid wood chips that are wrapped in plastic, or which have been processed in less green or environmentally friendly ways. A garden chipper If you have a shredder, you can avoid using dried woodchips, and can have more control over what is in the material. The best uses for wood chips in your garden include: Mulching around your plants Adding them to your compost pile Creating new growing areas with layered organic materials Making biochar Growing mushrooms in your garden Creating natural pathways Recreational groundcover for kids activities Creating new wildlife habitats See more detail on each of these uses below. 1) Using Wood Chips As Mulch One of the most common ways to use wood chips in a garden is as a mulch around your plants. However, while wood chips can sometimes be a wonderful mulch material, it helps to be careful about exactly where, how, and around which plants they are used. It is also important to choose the right wood chips for a particular project. One important thing to understand about wood chips is that when woody material breaks down, nitrogen is absorbed by the microorganisms involved in the process.1 This nitrogen is taken from the surrounding soil, and stored within the bodies of the micro-organisms, before being released when those micro-organisms die. Nitrogen Sequestration This sequestration of nitrogen is one of the main reasons why you have to be careful about where wood chips (with only wood, carbon-rich material) are used as mulch. Shredded branches which include some green vegetation along with the woody material will not lead to as significant a reduction in available soil nitrogen, since the leafy green material will provide extra nitrogen during the decomposition process.2 But where just woody material is used, as this material breaks down, there will be less nitrogen available in the soil for a period of time. This can sometimes have a detrimental effect on plants growing close by. “I have used wood chip as mulch around a variety of plants and have never found that it is detrimental to growth when laid on the surface,” says Horticultural Consultant Colin Skelly. “I am careful not to dig the wood chip into the soil to avoid nutrient sequestration. Where I have grown areas with and without mulch, the mulched areas have always demonstrated greater growth and health.” Shredded garden waste from tree pruning Placing non-composted wood chips around annual plants in a vegetable garden is sometimes a common practice. But it might not be the best idea, for the reason outlined above. The reduction in available nitrogen might compromise the growth – particularly of leafy annual plants. When wood chip is used in such a setting, it is best, therefore, to use it in combination with other organic materials, which are rich in nitrogen. Trees and shrubs will not typically be as affected by the temporary reduction in soil nitrogen as the woody material breaks down.3 And so using wood chips as mulch beneath trees, in a woodland or forest garden setting, or in a shrubbery or border, can be a good idea. The wood chip mulch can suppress grass and weed growth, protect the soil, conserve soil moisture, and create an environment that supports a fungal-dominant rather than a bacteria-dominant environment (which you want in a woodland or forest environment).4 2) Composting Wood Chips Heap of wood chips being used for composting If you want to use wood chips in a vegetable plot, or another area of your garden which has herbaceous plants, then composting it first is the best idea. When you compost wood chips before you use them, you avoid the issues with nitrogen sequestration, but can still take advantage of their properties and the nutrients they contain to maintain soil fertility. Remember, smaller chips will break down much more quickly than larger ones, and so will usually be better for adding to a composting system. Within a composting system, wood chips are treated as a ‘brown’ or carbon-rich material. They should be layered with plenty of ‘green’ nitrogen-rich materials for best results. Once the wood chips have been composted, along with other organic matter, the compost you create can be used as a valuable soil amendment throughout your garden. It can also be useful in making material to fill your pots and containers. 3) Using Them To Make New Growing Areas As well as composting wood chips in a separate composting system, another interesting use to consider is that you can compost them in place. In other words, you can create new growing areas where the organic materials are layered up to compost just as they would in a compost heap or bin. One of the easiest and cheapest ways to make new growing areas in your garden is to use a no dig approach. This involves layering materials like the ingredients in a lasagna to build new raised beds. You can use many materials from your own garden in these new no dig raised ‘lasagna’ beds. And wood chips are one of those materials. Layer carbon-rich materials like wood chips with nitrogen-rich materials like grass clipping, vegetable scraps and manures, then top these with compost, loam or topsoil into which you can plant. You can also use wood chips in the formation of hugelkultur mounds. These are basically lasagna beds which are mounded rather than flat on top. They contain a skeleton of rotting wood within which provides extra nutrients and stores water to prevent the growing area from drying out. The wood chips and other organic materials are layered around this skeleton of rotting wood. 4) Using Chips To Make Biochar In all of the options mentioned above, the wood chips help to improve the soil and add fertility. One final way to add organic matter and improve fertility in your garden is by making biochar – and wood chips can be used for this too. Biochar is charcoal, which has been enriched through steeping it in a nutrient-rich compost tea. Making biochar is something that can be beneficial, especially for gardeners with free-draining and nutrient-poor soils.5 The biochar can be buried in such soils to improve them, and can also increase soil carbon to help combat our climate crisis.6 5) Growing Mushrooms If you are focused on food production in your garden, then you may be interested to note that wood chips will not only be useful in growing plants. Wood chips can also be a useful replacement for soil when growing mushrooms in your garden. Wood chips in a shed, or in the shade beneath trees or shrubs can be inoculated with mushroom mycelium and kept moist to allow mushrooms to fruit. There are a number of different types of mushroom that you might be able to grow in wood chips in your garden. 6) Using Wood Chips For Pathways Of course, wood chips can also be very useful in other areas of your garden, outwith your growing areas. One obvious way that wood chips can be used is for pathways through your space. Wood chips which are larger will last longer, and won’t break down as quickly, but even smaller chips can be used for pathways. Though they will break down in place, and will need to be replenished over time, this can be useful, for example, around vegetable beds. The broken-down wood chip from paths through a vegetable garden can then be scooped onto the beds and used as a mulch. You can then replenish the paths and start the composting in place process over again. 7) For Ground Cover In Recreational Areas You can also use wood chips as ground cover for recreational areas in your garden. Again, these will break down over time and will need to be refreshed, but they can be a more eco-friendly and natural option than hard paved areas. 8) Creating Habitats For Wildlife With Wood Chips Finally, wood chips can also simply be piled in wilder corners, or placed into bug hotels or other wildlife-friendly features. A range of creatures will benefit if you use wood chips and other organic materials to make a range of habitats for the wildlife in your garden. These are just some of the main ways that you should think about using wood chips (ideally those you chip yourself from trees and shrubs) in your garden. References 1. The nitrogen cycle. (n.d.). Science Learning Hub. Retrieved March 27, 2023, from https://www.sciencelearn.org.nz/resources/960-the-nitrogen-cycle 2. Reduce Nitrogen Leaching. (2021, May 21). Yara United Kingdom. Retrieved March 27, 2023, from https://www.yara.co.uk/grow-the-future/efficient-farming/nitrogen-leaching/ 3. Woody waste: using as a mulch. (n.d.). Royal Horticultural Society. Retrieved March 27, 2023, from https://www.rhs.org.uk/soil-composts-mulches/woody-waste-using-as-mulch 4. Young, J. (2014, May 7). Fungal Soil: What Is It and Why Do We Want It? The Permaculture Research Institute. Retrieved March 27, 2023, from https://www.permaculturenews.org/2014/05/07/fungal-soil-want/ 5. Hertsgaard, M. (2014, January 21). As Uses of Biochar Expand, Climate Benefits Still Uncertain. Yale Environment 360. Retrieved March 27, 2023, from https://e360.yale.edu/features/as_uses_of_biochar_expand_climate_benefits_still_uncertain 6. Edwards, T. (2022, March 15). Carbon farming: applying biochar to increase soil carbon. Agriculture & Food. Retrieved March 27, 2023, from https://www.agric.wa.gov.au/soil-carbon/carbon-farming-applying-biochar-increase-soil-carbon
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Pruning Wisteria Can Breathe Life Into Mature Plants - Here Are Chris O’Keefe's Top Tips
IN THIS GUIDE Why Prune Wisteria? When To Prune Wisteria Summer Maintenance Pruning Winter Maintenance Pruning Pruning For Shape And Form Espaliered Wisteria Training On Structures Pairing With Mature Trees Standard Training Dramatic Pruning To Renovate Older Wisteria Learn how to prune wisteria to keep it healthy and looking its best. Wisteria is a beautiful climbing plant – take care of it and it can really have a strong impact in your garden. But learning how to prune your plants is important – wisteria, like many other plants, will look better and be healthier if you prune it annually, at the right times and in the right ways. This might seem a little complicated at first, so in this article, we will aim to demystify and help you understand the process, so you can do it correctly in your own garden. Why Prune Wisteria? Wisteria The main reasons to prune wisteria are: Stop them becoming too large – wisteria can outgrow their location. Improve light reaching new growth – so it grows well and flower buds form as they should. Better flowering – reducing the amount of foliage growth and encouraging short, flowering spurs means you will have more flowers on your wisteria. Neatness and practicality – pruning can keep wisteria on its support structures, not overly reducing light levels or preventing egress to different parts of your garden. And it can breathe new life into old, mature plants in need of renovation. For pruning, Chris O’Keefe from The London Wisteria Company says you need: A pair of clean, sharp secateurs A safe ladder If possible, a 2nd person to hold the ladder Garden ties to tie in any new leader shoots Good weather Garden bags When To Prune Wisteria Wisterias are typically best pruned twice each year. Once in the summer – in July / August – and once in the winter – in January / February. Renovation pruning when the plants are cut back much more dramatically can also be undertaken any time over the dormant period. (Considered after leaves have fallen in autumn, and before new growth emerges in spring.) Summer Maintenance Pruning Standard summer maintenance pruning takes place after the wisteria has finished flowering. “Summer pruning normally happens between late July to August,” says Chris. “We just prune back to 5 buds. This allows airflow through the wisteria and more sunlight is allowed in, which helps ripen the buds, creating larger flowers the following year. “We also prune out any stems which have grown into roof gutters and downpipes.” The main goal of this summer pruning is to control the size of the plant. You might wish to control the size of the plant to prevent it from getting into the guttering of your home, to prevent it from covering windows, or to prevent it from outgrowing a support structure on which it grows. Summer pruning will also ensure that light reaches the growth and that the plant does not put on excessive foliar growth at the expense of flowers. In July or August, cut back each of the green, newer shoots of the growth from the current year to 5-6 leaves each. Look for the position where the softer growth joins the main branches and count the leaves from this joint. Winter Maintenance Pruning Winter pruning is mostly about making sure that the plant is tidy, in shape and healthy before the growing season begins. “With any wisteria, winter pruning is key,” says Chris. “We always hard prune between January and March back to 2-3 flowering spurs. “We then remove any dead wood and tie in any new leader stems. This is also the correct time to add more support for your wisteria if it is needed. “In some larger jobs, we totally remove the wisteria from the wall, barn, or house and strip all old supports. “We then supply new supports such as vine eyes, rope wire, and turnbuckles.” This work can be undertaken at any point while the plant is not in leaf and is within its dormant phase, but January or February is usually best. Firstly, look for the three ‘D’s. Remove any branches or shoots which are dead, damaged or diseased, leaving the healthiest shoots behind. Then, you can also cut back the same shoots which were pruned in summer once more, to leave each one with just 2-3 buds. This will help to keep the size and shape of the plant in check, and also help to reduce foliage shading on the flowers of the following season. Pruning For Shape And Form As well as thinking about the normal summer and winter maintenance pruning, you can also think about pruning for a specific shape or form. Wisteria can be grown in different forms, and can be pruned in specific ways to suit the situation. Espaliered Wisteria For example, you might grow wisteria on walls and train it as an espalier. Espalier forms are a popular choice for fruit trees, but they can also work for many climbing plants – including wisteria. “I find the espalier system is especially neat for Wisteria, as it gives flowers space to hang,” shares Master Horticulturist Peter Lickorish. “I have trained wires the whole length of a fence, tensioned at each post, to achieve this look.” Pruning for an espaliered wisteria should also be undertaken as above, twice a year. And over time, a strong spur system can be formed through selective pruning. New growth from the base of the plant can be cut off at the base, or trained for replacement shoots. Training On Structures Wisteria which have long flowering racemes will look best if they are trained on structures that allow them to hang without being impeded by foliage or branches. Training these onto pergolas, or arch structures therefore can be a good idea. “If you have an arbor or pergola, then the wisteria will naturally grow in and around it and will most likely only need attaching in key areas,” says Chris. “If you’re planting young wisteria, it’s quite fun to twist the young stems so that in time they become gnarly, twisted stems. “Always be aware of overhanging wires, roof gutters, and downpipes, as wisteria is a climbing plant and will climb if left unsupervised.” Wisteria arch As well as thinking about the maintenance pruning described above, it can also be helpful to think about thinning racemes to give the best space to develop and dangle down to create a good display. Pairing With Mature Trees Wisteria can also be positioned at the base of large, mature trees and grown into them. Pruning in these cases, however, can be challenging. It can be difficult to distinguish and reach the shoots you wish to prune when these are entangled in a canopy. In such cases, wisteria may largely be left to their own devices. However it should be noted that the species can affect the growth of each other. A large and sprawling wisteria can swamp smaller trees, and when a tree has a dense canopy, this can affect how much the wisteria flowers. Pruning in such cases will often be hampered by practicalities of reach. But you should prune both the wisteria and the tree so as to maximise light levels for both and ensure their continued health. Standard Training If you are training a wisteria as standard, in a container or in the ground, it is important to make sure there is a sturdy central support. The stem should be trained vertically up the support rather than twined for greater strength. Once the growing tip reaches the top of the central support, remove the tip in February. This will encourage the formation of side shoots. The following winter, prune the side shoots to around 15 to 30cm. Repeat this process every winter to start to form the head of the standard form. As the head forms, prune shoots that are not needed to extend the head. Cut them back to 7 leaves each summer and cut them back harder in the winter as required. Dramatic Pruning To Renovate Older Wisteria In the case of older wisteria plants, more dramatic pruning may be required to renovate them, and to make sure they do not grow out from walls, or over windows, or spill off their supports. A wisteria that has not been pruned for some time may be overgrown and need some work. You will have to begin by identifying and removing sections of the plant which are not performing as well, or which are in the way. You can cut back sections to a young, strong branch or shoot that is lower down, or, in extremes – even cut them back drastically to the main trunk, or even to ground level, where necessary. Take some time, and make a plan about which branches and shoots you wish to keep before you begin. Your aim should be to create a healthy and open framework of spaced out branches. New growth can be trained in to replace older ones you have removed and used to fill any gaps in the framework. Once you have a framework you are happy with, you should then simply continue the maintenance pruning as above.
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Stop Cabbage White Butterflies Destroying Your Plants With These 5 Solutions
IN THIS GUIDE 1) Companion Planting For Brassicas 2) Distracting With Trap Crops 3) Attracting Beneficial Wildlife 4) Decoy Butterflies 5) Physical Barriers References Cabbage white butterflies may look pretty, but their caterpillars can quickly destroy garden crops. Though we should welcome wildlife in our gardens, it is important for those who are growing their own to be aware of this common pest, and the problems they can bring, especially for brassicas. Members of the cabbage family can be eaten rapidly if you get an infestation of cabbage white caterpillars, but there are a few things you can do to keep your plants safe. Cabbage white larvae The strategies for dealing with cabbage white butterflies in organic gardens revolves around a few simple things: Companion planting (which can confuse, distract or repel this species, at least to a degree) Attracting predators which prey on cabbage white butterflies and their caterpillars. Making the area a less appealing place for cabbage white butterflies to lay eggs. (By making them think the area is already occupied by other cabbage white butterflies, for example.) Creating physical barriers over your plants. The first two strategies can work to a degree. It is important to maintain a natural balance in the garden ecosystem so that all pest species are kept in check. But no matter how vigilant you are, the only sure-fire way to stop cabbage white butterflies from laying their eggs and caterpillars from destroying your plants is to keep them covered, and to form a physical barrier that these pests cannot breach. 1) Companion Planting For Brassicas Cabbage and spring onion companion planting Choosing the right companion plants to grow alongside brassicas involves thinking about plants that will disguise the scent of the brassicas and make it less likely that these butterflies will find them and lay eggs on them. Many aromatic herbs have a strong fragrance and when planted alongside brassicas as companion crops, can make these plants more difficult for cabbage whites to find. Examples include rosemary, thyme, mint, marjoram, sage, dill, and chamomile. Planting alliums (members of the onion family) alongside brassicas can also make them more difficult for plants to find. Cabbage whites may also be repelled to a degree by these strong-smelling plants. Remember, companion planting is also key to attracting beneficial wildlife. The plants in any garden should be chosen to encourage a wide range of beneficial creatures to the space. 2) Distracting With Trap Crops Cabbage white on nasturtiums It is also a good idea to think not just about companion plants for brassicas, but also plants to place elsewhere in your garden which attract cabbage whites and act as sacrificial trap crops. By planting trap crops elsewhere in your garden, you can lure cabbage whites away from plants which you are particularly keen to protect. Remember, cabbage white butterflies are important elements in the ecology of your garden.1 So you should not ever aim to eliminate them, but rather to protect the plants you wish to protect while offering them a home elsewhere in your garden. Nasturtiums, for instance, are one example of a trap crop.2 They will attract cabbage white butterflies, as well as several other common garden pests, which will often be attracted preferentially to feed on these rather than on more prized crops and garden plants. Sea stock, honesty plant, and Dame’s violet are three other attractant plants for cabbage white butterflies to consider. When these are placed in your garden, the butterflies may lay eggs on these rather than on your brassicas. Then when the caterpillars emerge, they will eat on the plants where they find themselves rather than gorging on your cabbage family plants. 3) Attracting Beneficial Wildlife Remember, the plants you choose for your garden and the habitats you create are key to pest control in an organic garden. Garden birds are very welcome if you want to stop cabbage white butterflies destroying your plants. Many garden birds are important predators of these pests. Attracting garden birds can be one way to keep pest numbers down. Parasitic wasp You should also be sure to welcome and attract other insect species (such as parasitic wasps, Cotesia glomerate), spiders, amphibians, reptiles and a number of mammals to your garden as these will also prey on cabbage white butterflies and their caterpillars and help keep their numbers down. It is also worth mentioning that domestic chickens can also eat caterpillars and help keep their numbers down. Just don’t give chickens access to your cabbages and vegetable plots – as chickens too will quickly eat the lot if given the opportunity! Instead, consider placing trap crops (as mentioned above) in an area where chickens forage. 4) Decoy Butterflies While we are not entirely convinced by the efficacy of this strategy, some gardeners swear that you can keep your plants safe from cabbage whites by adding decoy butterflies. These decoy butterflies, it is said, make it less likely that cabbage white butterflies will lay eggs close by as they believe that the area is already occupied. People make pretend cabbage white butterflies out of white paper, white fabric or white plastic (cut from old milk containers, for example). Place these among their brassica crops. While this strategy may or may not work, it could certainly be worth considering before you adopt more extreme solutions. 5) Physical Barriers Growing brassicas under netting Even when you adopt some or all of the strategies above, the only way to be absolutely certain that you won’t lose your brassica crop to cabbage white butterflies is to place physical barriers over the crop. Place a fine netting of 3-7mm size, mesh or other fabric row coverings over any cabbage family plants to keep them safe from hungry caterpillars. Though this may not be the most attractive feature in your garden, this is certainly the only way to avoid any losses at all when growing brassicas in your vegetable plot and ensure the netting is kept clear of the plant leaves.3 Make sure you place the barriers as soon as you plant brassicas as the cabbage white butterflies will soon appear. Observation is key and you will need to keep a close eye on your brassicas and look under leaves to make sure no eggs have already been laid. Physical barriers will only work if you place them before eggs have been laid. Otherwise, caterpillars will munch away under the covers and you could lose the lot! If you think you may have been a little late in placing your barriers, you may have to check over your plants carefully and remove by hand any eggs which have already been laid. Remember, both types of cabbage white butterfly present in the UK, Pieris brassicae (the large white) and Pieris rapae (the small white) lay eggs that become voracious caterpillars. But both can also be beneficial in your garden – so do not get try to get rid of them altogether – cover your key crops, and plant wisely so you can live and let live. References 1. What Is A Food Web? (n.d.). The RSPB. Retrieved March 20, 2023, from https://www.rspb.org.uk/birds-and-wildlife/natures-home-magazine/birds-and-wildlife-articles/food-chains/web-of-life/ 2. Wolfe, K. (2020, June 12). Trap Cropping. Retrieved March 20, 2023, from https://s3.wp.wsu.edu/uploads/sites/2073/2020/07/Trap-Cropping.pdf 3. Insect-proof mesh / RHS Gardening. (n.d.). Royal Horticultural Society. Retrieved June 23, 2023, from https://www.rhs.org.uk/prevention-protection/insect-proof-mesh
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Nerium 'Oleander' - Only A Handful Of Cultivars Are Hardy Enough For Our Climate
IN THIS GUIDE Overview Habitat & Growing Conditions Where To Plant How To Grow Oleander Oleander Plant Care Growing Varieties Common Problems References Oleander is a storied and reputed plant. This evergreen bushy plant is low-care, floriferous, and blooms throughout summer. It produces gorgeous flowers in colours from pure white to blood red. Tough and tender – that cliched phrase perfectly describes Oleander. Oleander can tolerate urban jungle heat and is even drought-tolerant to an extent – and it can make do with poor soil and heavy soil, that’s plenty tough. However, it is very tender – frost tender, that is. This tough-tender plant doesn’t have to deal with much frost, though, in the regions of the American South where it thrives as an introduced plant. Overview Botanical Name Nerium oleander Common Name(s) Oleander, Nerium Plant Type Shrub Native Area Mediterranean, North-West Africa, India Hardiness Rating H2-H5 (depending on variety) Foliage Evergreen Flowers Commonly shades of yellow, pink, white or red When To Sow (Indoors) March, April, May Flowering Months July, August, September, October Oleander is an evergreen shrub that can be short and ‘shrubby’ or develop a woody stem and grow up to a fair height so that it looks like a small tree. Dwarf cultivars settle at only 1-2m; the intermediate ones reach heights of 2.5-3.5m. The cultivars that grow into small trees can attain heights of up to around 7m. Almost all of them have bushy, open habits and almost all of them are profuse bloomers and flower right from the beginning of summer, sometimes even before, to the end of summer. Their colours include white, cream, all shades of pink from pale delicate pink to vibrant magenta pink, and deep rich reds. Oleander belongs to Genus Nerium, which includes a species count of just one! The sole species is Nerium oleander.1 The plant’s floral beauty has led it to be cultivated to quite some extent and many cultivars are known to exist. Habitat & Growing Conditions Oleander’s habitat and growing conditions are predominantly in mild Mediterranean climates near streams and other waterways, including coastal areas. Though the large majority of cultivars are hardy to Zone H3, a few are hardy only to Zone H2, while a few more are frost-hardy and suitable for growing in Zones H4 and H5. “Even in mild coastal areas, even a few degrees of frost are enough to prevent growing many Nerine oleander for a prolonged period,” shares Master Horticulturist Colin Skelly. “A handful of cultivars are available that are hardier for the UK and should satisfy a yearning for the Mediterranean.” Having been introduced to the Far East, it now grows wild in several of that region’s countries. Where To Plant Most residents of the UK will not be able to plant this frost-tender plant outdoors. Except for those fortunate enough to be living in balmy (relatively speaking) regions of the UK, most gardeners will perforce need to grow Oleander in a pot, container, or planter so that it can be overwintered indoors. Oleanders make wonderful patio and deck plants and as long as they get at least several hours of sun they’re great for the balcony too. A good-sized container or planter with an Oleander can fill any vacant spot in your garden with a gorgeous flowering plant. If you live in a secluded area by the sea in a mild part of the country and would like to build a windbreak or plant a decorative flowering bush, your jackpot is Oleander in all its cultivars. How To Grow Oleander Though Oleander is an evergreen shrub, the hardiness of most cultivars is only to H3 – which means that they cannot be grown outdoors in any but the warmest coastal parts of the United Kingdom, such as a small region in the south-west. However, you can search for a hardy variety, such as Hardy Pink and Hardy Red, and confidently grow these outdoors in your garden, though in a sheltered location, almost anywhere in the United Kingdom. Growing From Seed Oleander can be started indoors from seeds in early spring. Seeds may be started in a tray or in small pots. Either way, they should be sown in a sterile potting mix. Dampen the potting mix and just lightly dab in the seeds, about three to a pot. Seeds need light to germinate so they should not be covered – the lightest of sprinklings of the mix will suffice. Oleander seeds germinate after a comparatively long time – 15 to 20 days – so it will help if the conditions are as favourable as possible. First, the soil temperature should stay around 20-21°C. Next, cover, but do not seal, the pots with cling film or shrink wrap. Finally, keep watering the seeds but very lightly so that the potting mix stays just damp. As soon as the seeds germinate, remove the cling film and put the pots on a sunny windowsill or where the seedlings can get several hours of direct sunlight. If you started them in trays, transplant seedlings each to its own pot after they have developed two pairs of true leaves. If you started them in individual pots, thin as necessary or transplant. Transplanting After a year to eighteen months, the plant can be transplanted into its last appropriately-sized container as indicated by the eventual height and spread of the variety. An Oleander, depending on the ultimate size of the variety, may be grown in a pot, container, or planter. A halfway decent mixed loam amended with some compost will work very well for Oleander. It should drain well – overly wet soil or waterlogged soil is a big no-no for Oleander. In spring, after there is no danger of frost, the plant can be shifted outdoors – it would be wise to harden it for a week to ten days first. Oleander Plant Care Watering In the UK, Oleander should be placed in full sun. In most regions of the UK a mature Oleander plant’s water needs will be met by rain. During dry periods you will need to water it, though moderately. ‘Hardy Red’ Avoid letting the soil stay dry for more than a few days. Though Oleander is drought-tolerant, lack of water will affect flowering. Oleander does not care to be over-watered and should this happen, it will give you a signal: yellowing and yellowed leaves. Feeding Although Oleander does well without any fertilising, if you wish you could feed it with a small quantity of a balanced fertiliser in mid-spring, in either liquid or slow-release form. Otherwise give it a helping of compost. Growing Varieties Five varieties are outlined underneath with an eye to including a diversity of heights and spreads, and a matching diversity in floral shapes, forms, and colours. ‘Petite Salmon’ Has an odd name – for an Oleander, the plant is indeed petite at only about 1-1.8m and with the same spread, exhibiting a bushy, dense habit, but there is nothing salmony (or otherwise fishy) about its colour, scent, or anything else. The salver-shaped flowers are ‘pinwheel petalled’ and are in a delicate tone of baby pink. ‘Twist Of Pink’ Delivers a twist on the foliage too. The leaves are variegated, displaying irregular but striking yellowish vertical stripes. This cultivar bears double flowers in a deep, saturated pink, and it is the ruffled pink petals that give the plant its name. It reaches an ultimate height of just over 2m. It is a very popular variety on the other side of the pond. ‘Splendens’ An intermediate-size cultivar, reaching a height of 3-3.5m with about the same spread. It has a bushy habit, often vase-shaped. It bears bowl-shaped double flowers of a particularly neat and symmetrical form. They are of candy pink hue and have a satiny lustre. ‘Calypso’ A ‘tree-sized’ Oleander as it reaches an ultimate height of 4-5m with a spread almost as wide as its height. It is heat tolerant, even for an Oleander. It produces single, very full, salver-shaped flowers of an intense, eye-catching magenta-pink hue. This variety is especially popular in Florida and Southern California. ‘Hardy Red’ Indeed lives up to its name because it is hardy, at least by Oleander standards, being hardy to Zone H5. This variety is another large one, attaining a height of up to 4m with a spread of about 3m. This is one of the most attractive of all Oleanders because of its showy flowers. They are single, funnel-shaped, and of a riveting blood-red colour. Common Problems Oleanders are generally very pest-resistant and disease-free, especially if they are kept outdoors. If these plants are grown in a greenhouse, they may be subject to attack by glasshouse red spider mite and, less frequently, by scale insects and mealybugs. Indoor plants are more susceptible to scale insect infestation, and also to red spider mite and aphids to a lesser extent. You can avoid these problems by keeping indoor plants in rooms that are not heated and that have good air circulation. References 1. Nerium. (n.d.). Kew Royal Botanic Gardens. Retrieved March 21, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:30305280-2
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