Growing
Growing Aubrieta - You Can Even Grow This Plant In A Hole In The Wall
IN THIS GUIDE Overview Common Varieties How To Grow Aubrieta Planting Out Ongoing Aubrieta Care Propagating By Division Aubrieta is a no-care evergreen groundcover that easily covers problem spots, tumbles out of crannies and crevices, forms a soft green mat and produces a blanket of brilliant colour during spring. It is a first-rate choice for groundcover, rockeries, edging, planter companions, crannies and crevices and can even be grown in a hole in a wall! Rising only up to 10cm with a spread of 3-4 times its height, this low to no-maintenance evergreen is a great ‘plant-and-forget’ option to fill bare spots and inhospitable patches with year-round foliage of a cool green shade. Overview Botanical Name Aubrieta Common Name(s) Aubrieta, False Rock Cress, Purple Rock Cress Plant Type Perennial Native Area Eastern and Southern Europe Hardiness Rating H6 Foliage Evergreen Flowers Four-petalled, open, disk-shaped, 2cm wide, typically in tones of purple and pink, but also can be white When To Plant April to June and September There’s also that brilliant floral colour from mid-spring through to mid-summer. These mat-forming evergreens push up oodles of cheery little flowers in about the middle of spring. They can bloom in such profusion that, in the flowering season, a bank of Aubrietas will transform from a mat of green to a mat of vivid colour. The flowers are open and disk-shaped with four petals, and usually occur in tones of purple and pink, with white, cream and red hues less commonly seen, but still available. These little blooms are a top draw for butterflies and bees. Common Varieties The majority of Aubrieta varieties and more so the commonly-grown ones, are about 10cm tall and their flowers are typically up to 2.5cm across. A. ‘Doctor Mules’ Below, I’ve listed several varieties that can be sourced without much difficulty: A. ‘Doctor Mules’ (AGM) – This is probably the most widely available and popular variety. Its foliage is of a brilliant green shade and the abundant flowers are of a rich purple colour. A. ‘Royal Blue’ – Belies its name as the flowers are actually mauve-purple. A. ‘Kitte’ – has rich purple to violet flowers. The ‘Kitte’ series has relatively small leaves of a light green shade. This variety has flowers that are bigger than usual and sport a yellow eye. A. ‘Red Cascade’ (AGM) – The ‘Cascade’ series is especially vigorous and has foliage of a bright, deep shade. ‘Red Cascade’ bears flowers of a vivid magenta-red hue. A. ‘Regado White’ – This cultivar has a slow but steady growth pattern and its foliage is relatively hairy and sometimes serrated. The white-white flowers are set off by yellowy-green eyes. A. ‘Argenteovariegata’ (AGM) – This is not as vigorous as some other cultivars. It has soft mauve to lavender flowers but is equally valued for its foliage as the relatively small leaves are variegated in green, yellow and gold. A. ‘Kitte’ How To Grow Aubrieta These plants can easily be grown from seed. Although seeds may be started indoors in trays, this is unnecessary. It is far easier to sow this hardy perennial directly outdoors, assuming you want to grow it in the open ground. April to June is the best timeframe for sowing Aubrieta seeds outdoors. It would be advisable to check the weather forecast so you can sow these seeds when there will be more of a dry spell. Before sowing the seeds, till the soil with a hand hoe or rake. Sprinkle the seeds and cover them with a mere sprinkling of soil, or nudge the seeds partway down into the soil. Do not cover the seeds completely, as they need light to germinate. Water lightly with a watering can that has been fitted with a rose or a sprayer, taking care not to wash away the seeds. Keep the soil moist until the seedlings emerge. Another very reliable way to grow Aubrieta, particularly if you want a copy of the parent plant, is to take and plant semi-ripe cuttings in late summer to early autumn. Hardiness With a hardiness rating of H6, Aubrieta is fully hardy. Even Northern European winters will not affect it, as it can withstand temperatures down to -15°C. Light Requirements Aubrietas prefer a south or west-facing aspect, but they can make do with other less favourable aspects. What is most essential is that they be sited in full sun, which will maximise flowering and also ensure a pleasing, compact shape. They will struggle in partial shade and will fail to thrive in full shade. Preferred Soil Aubrieta grows best in lime-tending soil that is crumbly and not rich that has neutral to slightly alkaline pH. Therefore, a mixed loam of sand, chalk and clay with only a little organic matter is perfect. The soil should drain very well and should not stay damp or continuously moist for long periods of time. Planting Out Aubrietas are fantastic plants to cover bare spots where nothing else worth growing will take root. Such spots include chalky ground, crevices and crannies, verges and slopes, paved walkways, and holes or cavities in and on walls. This plant grows vigorously in many places and it is fairly commonly seen in the UK. Aubrietas often form an undulating mat atop walls and sometimes make a cascading vertical blanket along walls, as these unfussy, lime-loving plants grow in clumps in cracks and crevices. Young plants and seedlings may be transplanted into any of the inhospitable spots mentioned above. Simply get rid of any loose stones or weeds, fill in with soil, transplant the young plant and water it in. “I like to plant aubrieta in winter-spring hanging baskets to give one final eruption of colour before the display is swapped for summer plants,” shares Master Horticulturist Peter Lickorish. “From these baskets, after flowering, the aubrieta can be trimmed by a third and transplanted into a small planting pocket, or even the front of a border.” Ongoing Aubrieta Care Aubrieta is a seriously low-care plant. Other than the simple type of pruning outlined below, you may wish to feed established plants with a very light helping of organic fertiliser oriented to lime-loving flowering plants at the beginning of spring. None of this is necessary, as this plant flourishes in what are usually considered poor soils. Watering Water young plants regularly but do not soak the soil entirely and be sure it drains well. When watering mature plants, allow them to fully dry out before watering again. In many regions of the UK, you will not need to water these plants at all during the wet seasons. Established plants are drought-tolerant, but make sure that watering duties are not completely disregarded during any long stretch of dry weather. Pruning Aubrieta does not need any pruning, but it might be helpful to cut it back to maintain a compact size, especially if you have grown it in a wall, cranny or rockery. Such a cutback may be done anytime from the end of the flowering season to early autumn, but not any later. Cut back 25-50% of the plant. Aubrietas will become unkempt and straggly after three years or so, more so if positioned in partial shade, so this type of pruning will maintain a neat look. Common Problems In the UK, the only pests that the vast majority of Aubrieta cultivars are susceptible to are aphids and flea beetles. Both fall in the category of a garden nuisance rather than any serious menace and both are fairly easily controlled with biological controls and natural remedies. They can also succumb to powdery mildew, though this strikes these plants infrequently and can be treated fairly easily. Propagating By Division Aubrieta is not typically propagated by division because it does not spread aggressively and there is little reason to disturb the mat-forming groundcover it gradually produces. That said, its clumps can certainly be divided and re-planted. “The only caution is to check that clumps have roots,” adds Peter. “It is surprising how far the stems of this plant can spread from the original base and roots of the plant.”
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Feeding Tips For Rhododendron: 'Replace The Top 5cm Of Growing Medium Every Winter'
IN THIS GUIDE What Rhododendrons Need To Thrive Feeding Rhododendrons Growing In The Ground Feeding Container-Grown Rhododendrons Rhododendrons are popular flowering shrubs that can thrive in higher rainfall areas – particularly those with acidic soil. They are low-maintenance options if the right growing conditions can be provided and will often require very little care once established. If you are growing rhododendrons in the ground or in containers where you live, you might be wondering when and how to feed your plants to obtain the best results. When it comes to feeding rhododendrons, here are the basic things you need to know: Growing healthy rhododendrons always begins with the formation and protection of healthy soil, which is the foundation of an organic garden. Rhododendrons require a slightly acidic soil or growing medium that is moist but well-drained with plenty of organic matter. When growing in the ground, enrich the area with plenty of organic matter before planting and replenish this mulch each spring. When growing in a container, choose a good-quality loam-based ericaceous compost and replace the top 5cm of growing medium every winter. Feed pot-grown plants in the summer with an organic liquid plant feed. Read on to learn more about fertilising your rhododendron plants. Difficulty Easy Equipment Required Mulch, ericaceous compost, liquid fertiliser (optional) When To Feed Spring What Rhododendrons Need To Thrive The most important thing to understand when it comes to feeding any plant is where and how the plant accesses the nutrients that it needs to survive and thrive. Rhododendrons, like other plants growing in your garden, take their water and nutrients from the soil or growing medium in which they grow. It is always vital to remember that healthy plants growing in the ground in a garden depend upon the soil, whilst plants growing in containers depend on the growing medium. If the soil in your garden is healthy and the plants that you choose are well-suited to the soil conditions, this is the recipe for success, but remember too that their roots can only access nutrients if there is sufficient moisture. This is just as true when growing rhododendrons as it is when growing a whole range of other plants. To keep a rhododendron happy and healthy, feeding correctly begins with an understanding of the soil type where you live and the soil conditions that these plants require and desire. Rhododendrons will fare best in soil that is acidic, with a pH between 5-6. However, some are more tolerant of neutral or even mildly alkaline conditions. So, to create optimal growing conditions, you definitely need to know the requirements of the specific rhododendron type and variety that you are growing. Most rhododendrons will do best in rich, loamy soil with plenty of organic matter and will require moist yet free-draining soil or growing medium. Feeding Rhododendrons Growing In The Ground When growing rhododendrons in the ground, the first step should always be to think about how you can build healthy soil. Remember, rhododendrons need rich and healthy soil to perform at their best. Before planting out a rhododendron into its growing position in your garden, it is important to make sure that the soil contains plenty of organic matter. Some sources of organic matter that you might consider include well-composted conifer bark or wood chips, leaf mould, decomposing pine needles or composted bracken. Rhododendrons have shallow root systems and their roots should be only just below the surface of the soil. This means that enrichment of the immediate topsoil is most important. Acidic or neutral organic materials should be layered around the plants to a depth of at least 7.5cm after planting, keeping the main stem clear. It is from this mulch and the topsoil below that the plants should derive many of the nutrients that they require. As mulch breaks down slowly over time, the nutrients it contains are dispersed into the soil web, where they can be taken up by plant roots. This mulch should be replenished each year in the spring to provide slow-release fertility, conserve soil moisture, protect the shallow roots and suppress weed growth, as Katrina Clow from the Scottish Rhododendron Society explains: “Scrape off the top layer of compost and refresh in spring, making sure to use ericaceous compost.” Other than ensuring healthy soil and mulching each spring, rhododendrons growing in the ground typically won’t require any additional feeding. However, if growth or performance seems poor, you might also consider adding an organic fertiliser such as blood, fish and bone in the spring. “If the leaves turn a yellow colour between the veins, which may remain green, this is usually a clear sign of iron deficiency,” says Peter Lickorish, a Horticultural Consultant. “The root cause is often the wrong soil pH, so address this if you can by moving or repotting the plant. “If this is not possible, liquid seaweed with sequestered iron is an example of a fertiliser which can be applied as a foliar feed on a dry, cloudy day by spraying on the leaves at the stated dilution rate.” As long as the soil is healthy, rhododendrons will not typically require this addition. Feeding Container-Grown Rhododendrons If you are growing rhododendrons in containers then they will not be able to uptake the nutrients that they require from the soil. Instead, they will be reliant on the growing medium with which you have chosen to fill your containers. When growing rhododendron in containers, it is best to grow in a loam-based, peat-free growing medium. This can be either one that you purchase or one that you make yourself at home, but whichever option you choose should be slightly acidic. Make sure that the mix you choose is moist yet free-draining and that it does not become too compacted or waterlogged due to poor drainage. Even when you have a top-notch growing medium in your container, it is still best to replenish the top 5cm of the potting mix each winter. Then, every second spring, it is best to repot the rhododendron altogether. If you trim the roots then you can reuse the same container, but make sure that you use fresh potting mix to make sure that the plants get the nutrients they need. It is also a good idea when growing rhododendrons in containers to feed your plant through the summer months with a good quality organic liquid plant feed. Again, remember that this should be a feed suited to ericaceous plants. Keep the above tips in mind and you should find it easy to make sure rhododendrons get the nutrients they need.
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7 Common Cacti Problems And Solutions Shared By Nursery Growers
IN THIS GUIDE 1) Overwatering Or Poor Drainage 2) Underwatering 3) A Lack Of Light 4) Excessive Brightness 5) High Humidity 6) Cold & Wet Winter Conditions 7) Sap-Sucking Pests There are many cacti that can be grown as houseplants in the UK and even a few that are hardy enough to be grown outdoors in our climate. These are fascinating plants adapted to dryland or desert growing conditions. It is the ways in which these plants have adapted to low rainfall environments that dictate how they are cared for and where they are best grown. Whichever cacti you are growing and wherever they are placed, it is important to pay attention to the needs of these plants and to understand what they require. Most of the most common problems and issues when growing cacti are caused by: Overwatering or poor drainage. Underwatering. A lack of light. Excessive brightness. High humidity. Cold and wet conditions in winter. Sap-sucking pests. As you can see, many of these problems and issues can easily be avoided or tackled by placing a cactus in the right spot and caring for it correctly. Read on for a more in-depth discussion of the different things that can cause problems with these plants and their subsequent solutions. 1) Overwatering Or Poor Drainage “I grew up in California amongst vineyards, orchards and cactuses,” says Alley Marie Jordan, a garden historian. “Instead of a hedge like most UK houses have, we marked our garden with cactus walls and palm trees. “In California, you have to search for shade and water access, whereas in the UK you plant for good drainage and look for sun!” Since cacti are adapted to very dry environments, some of the most common problems relate to overwatering or poor drainage. It is important to make sure you do not overwater a cactus because this can damage the plant roots, cause growth to be stunted, lead to blistering and rot can set in. These plants require free-draining conditions and as well as making sure that you do not overwater, you also need to make sure that drainage is excellent at all times. “This can be achieved by generously mixing horticultural grit with compost and ensuring drainage holes are present and not likely to clog up,” shares Master Horticulturist Peter Lickorish. Excess water must always be able to drain away freely, otherwise, when left in standing water or boggy conditions, the roots can often rot. When thinking about how much water plants need, you should always consider the native environment of the plants you are watering, as Daniel Jackson, the Owner of Ottershaw Cacti, explains: “Their native environments are often very dry, such as the bright and hot lands of South Africa and Mexico, not the naturally soggy lands of Surrey!” The amount and frequency of rainfall in their native range will help you understand how much water they will require and the frequency with which they should be watered. “Only water after the soil has dried out and reduce this in the winter months,” says Darren Evans, the Plant Manager at Pugh’s Cacti. 2) Underwatering However, do not think that because cacti come from desert environments, they do not need to be watered at all. Of course, cacti can be very drought tolerant, but they do need some water. Under-watering cacti can lead to shrivelling and the growth of the plant may slow considerably or the new growth might be misshapen. “Increase watering as the weather warms in spring and only reduce watering in the Autumn,” advises David Ennals, Owner of Coach House Cacti. 3) A Lack Of Light If cacti do not get enough light, they can also end up being weak and misshapen. Indoors, cacti will generally need a bright spot, but one out of direct light. Outdoors, hardy cacti will typically need a sunny spot that is as warm and sheltered as possible. “We often get asked ‘why does my plant look like this?’ and it’s usually due to insufficient light levels on a window sill inside the house,” Tom Adkin & Giulia Consolandi from Piccolo Plants Nursery share. “Look into the natural environment that the plant would grow in and you will soon find the perfect spot for it.” 4) Excessive Brightness Cacti generally need a bright location when grown indoors but can encounter problems in intense direct sun. Too much sun is one potential cause of a problem known as cactus corky scab. This problem causes brown spots to arise on the skin of the plant, which gradually form into calluses or scabs shrunken into the surface. Move the plant out of intense sunlight and the problem may resolve itself. 5) High Humidity Cactus corky scab can also be caused by high humidity, so it is important to work out whether too much bright sunlight or too high a humidity level is to blame. Reducing humidity within your home might allow you to solve this problem when growing cacti as houseplants in our humid climate. “For this reason, some combinations of houseplants just do not work well, such as cacti and most orchids, because the humidity cannot be at the right level to please both,” says Peter. 6) Cold & Wet Winter Conditions “After the growing season, cacti are usually ready for a rest, so, during the winter months, require time to recover and get through the colder months,” says Darren. “Because of this, make sure indoor-grown cacti are not kept by a radiator or heater throughout the winter. “As a general rule, keep your cacti at around 10°C from November to February.” For hardy cacti that are grown outside in the garden, cold temperatures can cause dieback on the plants and create patches of discolouration on their skin. However, the main problem for gardeners who have cacti outside over the winter months is not the cold, but the wet. Even cacti that can withstand colder temperatures will often need to be protected or brought indoors due to the high levels of precipitation in the winter months. Growing under a porch may be the solution. “Balancing moisture and temperature is important,” shares Peter. “Remember that cold air can hold less moisture, so the relative humidity increases. This could be a real problem for overwintering cacti, so remember to select somewhere dry and keep humidity low through ventilation. “However, avoid draughts. In a greenhouse, opening up the doors and vents on a warm winter day can help remove residual moisture. In a larger greenhouse, low vents or louvres could be opened slightly to circulate air, but keep cacti on shelving away from draughts.” 7) Sap-Sucking Pests This final category of problem is a little different to all of the above because this is a problem that can arise regardless of where you place a cactus and the care you provide. A number of sap-sucking insects can potentially take an interest in cacti and can cause a serious problem in larger numbers. These can include scale insects, red spider mites and mealybugs, all of which can be common problems when growing indoors or under cover in a greenhouse or polytunnel. The key thing is to remain vigilant and nip any pest problems on houseplants in the bud before they get out of hand. Treatments based on oils and soaps, sold for houseplants, can work well. These key problems and issues listed above are not uncommon when growing cacti, but are largely easily avoided. As long as you place cacti in the right environment and provide the right environmental conditions, you should still find that even though issues can arise, these plants are incredibly forgiving and relatively easy to grow.
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6 Issues That Often Arise When Growing Clematis, According To Specialist Growers
IN THIS GUIDE 1) Shoots Wilting & Dying Back 2) Stems Emitting A Stinky Ooze 3) Leaves Coated With Grey Growth 4) Leaves With Holes In Them 5) Leaves Curled & Sticky 6) Failing To Flower References Clematis are popular climbers that can find a place in many UK gardens. They can often be the right plants for the right places and thrive in our climate and most different conditions that we can provide. However, certain growing problems can arise – and troubleshooting those problems will usually require observation skills; then trying to work out the root causes in order to fix them. We take a look at some of the most common symptoms of issues that can arise when growing Clematis, including: Shoots wilting and dying back. Stems emitting a stinky ooze. Leaves coated with grey-white growth. Leaves with holes forming in them. Leaves becoming curled and sticky. Your plant failing to flower. If you have encountered one or more of the issues above, read on to learn more. 1) Shoots Wilting & Dying Back Sometimes, slugs and snails may feed on clematis stems, leaving them weak, pale and silvery in hue. Young shoots may be damaged enough to wilt and die back. Unfortunately, shoots that are wilting and dying back at the tips could also be a sign of a much more serious problem. These symptoms can denote a problem with the roots and could be caused by diseases such as Phytophthora root rot or honey fungus. In container plants, roots may be damaged by vine weevil grubs. Overwatering or waterlogging due to using too large a container or having poor drainage can also lead to roots rotting. Sometimes, a clematis may also have shoots that wilt and die back at the tips when the soil or growing medium is too dry and hot. “Although they love sunny conditions, consider sheltering their roots with a tile or other planting and remember that establishing Clematis are thirsty plants,” shares Master Horticulturist Peter Lickorish. With large-flowered clematis hybrids, a fungal disease called clematis wilt could also be the problem. However, don’t jump to the conclusion that this is what it is before you have ruled out the other potential issues above, as many species of clematis are resistant to clematis wilt.1 2) Stems Emitting A Stinky Ooze If one of the stems of a clematis plant has died back and a stinky ooze is coming from it, this is likely a problem called clematis slime flux.2 This is a bacterial disease that can be fatal but, fortunately, it is possible to save the plant by pruning out the affected area. Early signs of this problem include yellowing and wilting leaves in spring and early summer, often just on a part of the plant. Occasionally, the clematis might fail to leaf out in the spring altogether. The problem arises when a stem has been damaged and bacteria has got in. Protecting plants from cold winds can help avoid this issue. 3) Leaves Coated With Grey Growth One of the most common problems experienced when growing clematis is powdery mildew. This is a fungal problem which causes a whitish-grey, dusty coating to appear on leaves, stems and flowers. Powdery mildews affect a wide range of different plants, clematis included, and while a mild infection might not harm the plant too much, a severe one can dramatically restrict growth and vigour. “Powdery mildew can be an issue, especially in newly planted clematis,” shares Peter Skeggs-Gooch, the owner of Thorncroft Clematis & Climbers. “This strikes while the root can not sustain all of the top growth the plant has built up and can be rectified by pruning back the plant by as much as half and watering generously. “Add Epsom Salts to the water once every couple of weeks for 1 month to improve plant health.” As mentioned above, prune out affected shoots promptly to prevent the problem from spreading and clear up and dispose carefully of all fallen leaves to reduce the number of infectious spores in the vicinity. “Too much shade and poor airflow can exacerbate the problem, along with plants suffering stress for a variety of reasons – such as not enough room for their generous root system,” says Peter. 4) Leaves With Holes In Them If you find holes in the leaves of your clematis, then a number of insects can be to blame. Lots of different species feed on these plants, including slugs and snails, earwigs and a number of moth caterpillars. “I would say the most common problem is damage from slugs on the brand new shoots in the spring,” says Marcel Floyd, the Owner of Floyd’s Climbers and Clematis. If young leaves have torn edges and little, brown-edged holes, then you might have a problem with capsid bugs. Work on boosting biodiversity, as natural predation is generally the best way to deal with pests in any organic garden. 5) Leaves Curled & Sticky Curled and sticky leaves on clematis are most likely to be signs of an aphid infestation. The honeydew that these aphids excrete can also lead to sooty mould growth on your plants. Aphids in a garden are not a problem per se, but they can be problematic if their numbers get out of control. So, again, boost biodiversity and attract natural aphid predators, including ladybirds and blue tits, to your garden to keep everything in balance and aphid numbers under control. 6) Failing To Flower If a clematis fails to flower, this is typically due to some problem with the environmental conditions. Make sure that you have met the various environmental needs of the clematis you are growing. Generally, clematis needs moist but well-drained soil. They need to have their roots cool and shaded, but sun for the upper portions of the plant. Too much shade can inhibit growth and flowering, so make sure your clematis has enough light, but cool shade for its roots. “Young Clematis can be delicate, so I recommend keeping recently bought or propagated young plants in generous, but not overly large, pots until they have a few well-developed stems reaching at least 30-40cm,” advises Peter. “This allows them to be planted around 5cm deeper than their level in the pot, which aids establishment and is a unique trick to Clematis. “Planting them out at this stage helps them rise above dense borders – I have known them to simply be smothered and snuffed out by other plants if they’re not well established when planted.” If environmental issues are not to blame, the lack of blooms on a clematis might be due to improper pruning. Pruning at the wrong time might mean that you may have accidentally removed the part of the plant from which the flowers would usually grow. If the clematis is in a perfect spot and you have not pruned wrongly, nutrient deficiency might be to blame and you may need to delve deeper into the nutrient content of the soil in order to work out what your plant is possibly missing. There are, of course, other things that can go wrong when growing Clematis. However, looking at the issues above will often help you find the cause of any growing problems or issues. References 1. Clematis wilt / RHS Gardening. (n.d.). Royal Horticultural Society. Retrieved May 10, 2023, from https://www.rhs.org.uk/disease/clematis-wilt 2. slime flux. (n.d.). Clematis on the Web. Retrieved May 10, 2023, from https://clematisontheweb.org/new-disease-slimeflux.cfm
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How To Train Wisteria Twice A Year: The Objective Is To Control Its Climbing
IN THIS GUIDE Support Structures For Wisteria Structural Considerations When & Where To Train Wisteria Choosing Fasteners To Use Training Wisteria Around Its Support Wisteria is often called Wisteria Vine because it is a vigorous grower and can climb rapidly. It ascends vertical structures by twining and spiralling around them with its strong stems. Where Wisteria is concerned, it is not so much a question of training it to climb because it climbs all too well by itself. Instead, the objective is to control its climbing by training it. Wisterias are usually divided into four classes; Japanese, Chinese, American and Downy or Silky. No matter which type you have, the essentials of training remain the same, as do the essentials of its lush beauty over the spring-summer season. Difficulty Easy Equipment Required Fasteners; arbour, pergola or archway (optional) When To Train June to July and February to March Support Structures For Wisteria Although a Wisteria vine has to be trained, what exactly you are training it on is another important consideration. “We always recommend using good support, as with any wisteria, they start off small, but over time will grow quickly and gain weight with their twisted trunks,” says Chris O’Keefe, the owner of The London Wisteria Company. The usual and customary garden trellis might not be the best choice, as if it is too lightweight, sooner or later both Wisteria and trellis will come down. “Wisteria also needs space to hang, and a trellis lends itself to denser growing climbers, like Clematis,” shares Master Horticulturist Peter Lickorish. Some ideal support structures for a Wisteria include an open framework for an arbour, a big pergola or an archway. A boundary wall or a pillar would work out, but it would be helpful if smooth, unbroken surfaces were first prepped to give the vine something to climb on. I recommend growing a Wisteria, especially a Japanese or Chinese type, against the wall of your dwelling. In any and all cases, the support structure must be very sturdy and properly anchored into the ground. These considerations are all the more important if you live in a windblown area. Structural Considerations To prep a smooth, unbroken surface, string horizontal lengths of wire, spaced apart vertically by about 30cm. “Depending on the surface, vine eyes can be screwed in at metre intervals and used to tension the wire,” shares Peter. Although you can use any wire for these robust vines, it is best to use smooth, PVC-coated or vinyl-coated wire. Installing wide, large-holed netting in front of a boundary wall will offer a convenient face for the vine to climb around. Another option is to mount plastic mesh fencing on the structure, particularly if it is a thick, broad pillar. A pole or a narrow pillar will not need any prepping; Wisteria will twine around these, but it is best if the pole is connected to something else, such as an arch, giving room for the flowers to hang. Netting or fencing only serves to get Wisteria started on its way. They are not meant to be permanent supports and sooner or later they may degrade and break up. By then, the Wisteria should not need them anymore. The reason is that the climber’s lower stems will have thickened and become woody, so the plant will have its own load-bearing support to a partial extent. Also, the upper branches will have ascended to the top of the real structure and, in going over it, will also provide support, as the climber will partially hang over and off the structure. Of course, if the support structure itself is trellis-like or has horizontal or vertical bars, then a Wisteria will have no trouble from the get-go as it will twine and coil around its elements. When & Where To Train Wisteria In general, a Wisteria should be transplanted 15-25cm from the support structure. The exact distance depends on the type of Wisteria and its ultimate size. After transplanting a Wisteria, do not prune it for at least a year; training too should be kept at a minimum during this time. Train Wisteria twice a year. The first phase would be as fresh growth emerges in spring, around February to April, and the second phase would be in the June-July timeframe, right after summer pruning. In the first phase, you will mainly be training young shoots and pruning to trim side-shoots into flowering spurs. In the second phase, you will mainly be pruning and training growing stems. “I like to treat wisteria almost like an espaliered fruit tree,” shares Peter. “I find this gives a really neat finish and allows some transparency if the brickwork or fence behind a wisteria is attractive too. “I space horizontal wires on either side of the main ‘trunk’ at 30cm intervals up the surface, such as a wall, fence or the sides of a pergola. “Select a single stem to branch at each level of wire, on either side, and shoots along the length of this stem can be pruned to 7 buds in July and 2 buds in February.” Choosing Fasteners To Use To train a Wisteria, fasteners are only required when the support structure has to be fronted with netting, as described above. If it consists of a lattice-like structure, bars or uprights, fasteners are not necessary, though they can still be useful. The best types of fasteners are high-quality commercial garden tie wire, garden twist ties or narrow fabric strips. “If you wish to grow your wisteria against a wall, I highly suggest using wire support,” Chris suggests. “This is a simple system which uses vine eyes which are drilled and then screwed into the wall or house brick. “We then secure rope wire which threads through the vine eyes before being tightened by a turnbuckle. “This system is quick and can take a lot of weight if the wisteria is trained correctly.” That said, Wisterias, notwithstanding their lovely and graceful form, are seriously strong plants. They do not need pampering and you can get away with using ordinary twist ties, provided that they are long and strong enough, and other types of ties, such as packing tape. Training Wisteria Around Its Support If a green shoot is anywhere close to the support structure that you want to train it into, simply grasp it between your fingers and twist it around the vertical a couple of times, then grasp it with part of the support structure. After, gently press it in place for a minute or so, being careful not to squeeze the growing tip. This is how I have sent shoots of twining climbers up pillars and posts and they have automatically further twined and coiled, growing and thickening over time. Chinese Wisterias twine counterclockwise and Japanese Wisterias clockwise, but if you ever need a clue, simply glance at the direction mature stems on the plant are twined and twirl the under-training shoot in the same direction. This method will not work for shoots that are very long and growing off to one side or that seem to have a mind of their own. For these, you will have to use fasteners. However, even shoots that are not exactly convenient can be trained without fasteners if the support structure has a lattice-like face. Thread these shoots through three or four holes while twining them around the rods and bars. Otherwise, simply position the shoot in the direction where you wish to train it and stick it to a structural element by twisting a tie around stem and element, or by attaching a loop of tape around it. Whatever fastener you use, it should be firmly fastened but should not cut into the shoot or press it against the element; leave a bit of space for the stem, as it will fill out. Unless you have other plans, your goal should be to coat the support structure in an even layer of twining stems for a pleasing appearance. So, in order to achieve that goal, if you see two or three healthy stems starting to twine too close, gently untwine one shoot, preferably the newer, looser one, and fasten it to a nearby bare part of the structure. As for overriding Wisteria decision-making, if, one fine morning, you spot a very fresh shoot twirling itself around a garden chair that is close by your pergola, you know what to do. Do keep in mind that training Wisteria goes hand-in-hand with pruning it, so for further particulars, please see our pruning guide.
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This Is Where You Should Keep Your Aloe To Help It Survive Winter Successfully
IN THIS GUIDE Where To Place Aloe During Winter Watering Aloe In Winter Does Aloe Need To Be Fed In Winter? Aloe vera is a popular houseplant and is very easy to grow. It can be placed out into a garden in summer or kept indoors all year round but cannot survive winter outdoors in most of the UK. The good news is that even if you’re not always the most careful and conscientious houseplant gardener, Aloe vera can take some neglect and withstand even the least green-fingered of attendants. In winter, the care required by these plants is even lower and less demanding than it is during the summer months. However, while you won’t need to do much when caring for an Aloe vera plant in winter, you will have to make sure that you place it in a suitable location. Below, we’ll clarify where to place an Aloe vera in winter and confirm what you do and do not have to do when you have one of these plants in your home during the colder months of the year. Where To Place Aloe During Winter Aloe vera plants can be placed outside in a garden for summer or kept indoors even during the warmest part of the year. However, over the coldest months, they do need to be kept indoors or under cover in a frost-free and relatively warm location. “They require some heat in winter,” says Les Pearcy, Chairperson for the Haworthia Society. “I grow my Aloe plants in a greenhouse which is kept a few degrees above 0°C, but this means that I tend to keep them dry in the colder months.” Temperature Aloe vera needs temperatures that do not regularly drop below 10°C and 5°C is their absolute minimum. The temperatures should ideally be a little warmer than this and care should be taken to position Aloe vera so that the temperatures in the vicinity do not fluctuate too greatly. This means that you should not place an Aloe vera in a cold draft or too close to a heat source. Make sure you do not place your plant too close to an oven, stove or radiator and look out for cold draughts from windows and doors. Light Requirements These plants also need a good amount of light, which can sometimes be challenging to provide during the winter months. When not using grow lights, it is important to make sure that you place an Aloe vera on a bright windowsill or another sunny spot over the winter months. Humidity It is best to keep an eye on the humidity; around 40% is ideal for your Aloe vera plant. An Aloe vera will not enjoy being in too humid an environment in your home but nor should you allow humidity to drop too low in winter. “Signs that the humidity is too high include browning of the leaves, which can eventually turn mushy, or raised white spots on leaves, known as oedema,” shares Master Horticulturist Peter Lickorish. Watering Aloe In Winter Overwatering an aloe in winter is one of the most common mistakes that people make. It is always important to remember that Aloe vera has only very modest water needs in summer and requires even less water over the winter months. Over the winter, an Aloe will not grow and enters a state of dormancy. It will only need watering around once a month, maybe even less. Simply begin watering more frequently again in the spring. Does Aloe Need To Be Fed In Winter? Aside from checking the plant and watering very occasionally, Aloe will be the ultimate low-maintenance houseplant over the winter months. You do not need to feed it through the coldest part of the year and will only need to worry about this and other potential jobs in the spring when the plant returns to active growth.
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These Are The Incredible Varieties Being Grown By Orchid Societies And Nurseries
IN THIS GUIDE 1) Cymbidium ‘Dorothy Stockstill’ 2) C. erythraeum 3) C. lowianum 4) C. ‘Nagalex’ 5) C. ‘Tiger Tail’ 6) Dendrobium ‘Berry’ 7) D. kingianum 8) D. nobile 9) Miltonia ssp. 10) Oncidium naevium 11) Paphiopedilum ‘Clair de Lune’ 12) P. insigne 13) P. ‘Leeanum’ 14) P. ‘Pinocchio’ 15) Phalaenopsis amabilis 16) P. ‘Dover’ 17) P. ‘Picasso’ 18) P. ‘Sunshine’ 19) P. ‘White Apple’ 20) P. ‘Yellow Lightning’ Orchids are notorious for being fussy plants, but some are easier to grow as houseplants than you might think. “When selecting an orchid, your uppermost considerations, other than aesthetics, should be its season of flowering, whether it’s terrestrial or epiphytic, its light preferences, and its temperature needs,” shares Peter Lickorish, a Master Horticulturist. “Although most orchids need differing day and night temperatures, they can be broadly classified as warm-growing, intermediate-growing or cool-growing. For light levels, some prefer longer durations of less bright light, while others need brighter conditions.” Moth orchids, Phalaenopsis, are the most commonly grown as houseplants in the UK. However, as you can see from the list below, there are not only many of these orchids to choose from but also many other orchid varieties that you might grow. Spotted in Kew Gardens “It is indeed challenging to choose a favourite orchid type or variety, as they each possess their own unique characteristics and charm,” says Daniel Toor, Owner of the specialist nursery The Dark Orchid. “I am constantly enthralled by the vast array of orchid shapes, sizes and colours, as well as the intricacies of their leaves, bulbs, roots, growth patterns and preferred environments. “To me, each orchid is like a character with its own distinct appearance, requirements and personality. “All in all, it is their diversity and beauty that ignites my passion for growing these fascinating plants.” Let’s explore just some of the highly regarded species and hybrid cultivars to help you find the right orchid for you and your home. 1) Cymbidium ‘Dorothy Stockstill’ COMMON NAME(S): boat orchid ‘Dorothy Stockstil’ HARDINESS RATING: H1C FLOWERS: red FLOWERING SEASON(S): winter / spring SIZE: 0.5-1m in height, 0.5-1m spread This is a highly floriferous boat orchid which bears reddish-brown flowers with a maroon lip from winter into the spring. It should be grown in a neutral and well-drained loam, in a reasonably bright location out of direct sunlight, and needs minimum temperatures of 16°C during the day and 10°C at night. This hybrid variety, with its pendulous flower spikes, looks good growing in a basket. 2) C. erythraeum COMMON NAME(S): Indian cymbidium HARDINESS RATING: H1C FLOWERS: red, green and white FLOWERING SEASON(S): autumn / winter SIZE: 0.5-1m in height, 0.1-0.5m spread Requiring around the same temperatures and conditions as the above, this boat orchid has bright green leaves that sometimes have dark spots. In autumn and during the winter, it has long arching stems that carry around a dozen blooms. These are around 8cm across and have 5 narrow outer petals that are green with red spots and a tubular centre that is green with dark red markings and a white lip. 3) C. lowianum COMMON NAME(S): low’s boat orchid HARDINESS RATING: H1C FLOWERS: green and red FLOWERING SEASON(S): autumn / winter SIZE: 0.5-1m in height, 0.5-1m spread This boat orchid is a large epiphytic species that grows to around 90cm in height. It will grow best in cooler conditions. The flowers are a vivid shade of apple green, with deep red edges to the lip, and these bloom on long, arching stems from autumn through to the winter and sometimes into early spring. Again, these are houseplants, with a hardiness rating of H1C. 4) C. ‘Nagalex’ COMMON NAME(S): cymbidium ‘nagalex’ HARDINESS RATING: H1C FLOWERS: green and white FLOWERING SEASON(S): summer SIZE: 0.5-1m in height, 0.5-1m spread Another option which can bloom over a long period of time, this boat orchid is extremely floriferous and can bloom continuously for more than three months. This is another potential houseplant that needs daytime temperatures of 16°C and 10°C during the night. The flowers are a yellowy-green hue with a white lip and they have a sweet fragrance. 5) C. ‘Tiger Tail’ COMMON NAME(S): tiger tail cymbidum HARDINESS RATING: H1C FLOWERS: yellow and purple FLOWERING SEASON(S): winter SIZE: 0.1-0.5m in height, 0.1-0.5m spread A dwarf, free-flowering terrestrial orchid that grows to around 30cm in height and spread, this option has long linear leaves and produces yellow to olive green flowers with white tinted peachy lip on gently arching spokes. These flowers bloom in the early winter. 6) Dendrobium ‘Berry’ COMMON NAME(S): rock orchid ‘berry’ HARDINESS RATING: H1B FLOWERS: pink FLOWERING SEASON(S): spring / summer / autumn / winter SIZE: 0.1-0.5m in height, 0.1-0.5m spread “At our nursery, we love to grow many of the species, especially dendrobiums,” shares the owner of Burnham Nurseries, Sara Rittershausen. “We have some that flower in any season and enjoy the cooler temperatures, and many have a lovely scent which is a real bonus!” This small, terrestrial orchid is a hybrid of D. kingianum (see below) and D. ‘Mini Pearl’. It grows around 38cm tall and 30cm wide. It has leathery green leaves and purplish pink flowers which are 2cm across, borne on sprays which grow upright from the pseudobulb tips in the spring. Daytime temperatures of 18-25°C and nights above 12°C are required. 7) D. kingianum COMMON NAME(S): pink rock orchid HARDINESS RATING: H1B FLOWERS: pink, purple and white FLOWERING SEASON(S): spring SIZE: 0.1-0.5m in height, 0.1-0.5m spread This orchid is slightly larger than the hybrid listed above. It is an epiphytic orchid with erect stems and fragrant flowers in purple, pink or white, with a veined or blotched lip that features hints of red or purple. These flowers are borne in racemes up to 15cm long in the early spring. 8) D. nobile COMMON NAME(S): noble dendrobium HARDINESS RATING: H1C FLOWERS: pink FLOWERING SEASON(S): winter / spring SIZE: 0.1-0.5m in height, 0.1-0.5m spread Another epiphyte, this orchid is often evergreen in cultivation. It grows 30cm in height, with ovoid leaves around 5-8cm long. From winter into spring, these orchids bear trusses of fragrant flowers with a rose pink hue and a deep maroon lip. Grow in well-drained acidic or neutral soil in a suitable orchid compost, with temperatures between 18-25°C by day and a minimum of 10°C at night. 9) Miltonia ssp. COMMON NAME(S): pansy orchid HARDINESS RATING: H1B FLOWERS: varies FLOWERING SEASON(S): spring SIZE: 0.1-0.5m in height, 0.1-0.5m spread If you are looking for something different to try, one of the pansy orchids within the Miltonia genus might be an option to consider. These have large, open blooms in a range of different shades from white through yellow and pink. Often, they are marked attractively in contrasting colours. They can be grown in cool to intermediate temperatures and should be kept in bright but indirect light indoors. 10) Oncidium naevium COMMON NAME(S): spotted oncidium HARDINESS RATING: H1B FLOWERS: white and red FLOWERING SEASON(S): spring / summer SIZE: 0.1-0.5m in height, 0.1-0.5m spread This is another orchid that might be grown inside the home in a bright conservatory greenhouse. It is an epiphytic orchid that has a pseudobulb from which new growth emerges. The leaves that come from the pseudobulb are around 20-30cm long and the flowers, borne on longer, arching stems in winter and spring, are sweetly scented. These blooms are white and star-shaped, with little red spots and a yellow spot at the centre. Six or more blooms may develop on mature plants. The maximum daytime temperature is 25°C and 8°C is the minimum at night. 11) Paphiopedilum ‘Clair de Lune’ COMMON NAME(S): slipper orchid ‘Clair de Lune’ HARDINESS RATING: H1A FLOWERS: green and white FLOWERING SEASON(S): spring / summer / autumn / winter SIZE: 0.1-0.5m in height, 0.1-0.5m spread Slipper orchids are another type to consider if you want to grow orchids at home. “I have a mixed collection of a number of genera but specialise in Paphiopedilum,” shares Ken Griffiths, the Chairman of the Bournemouth Orchid Society UK. “I particularly like them for their form, variety of colour and, in some, the beauty of the leaves. “There is a very active specialised Paphiopedilum Society in UK, which is the only one of its kind devoted to a particular genus.” This slipper orchid has leaves that are mottled and dark green, and single flowers up to 10cm across, which are carried on upright stems that are between 15-20cm tall. The apple green ‘slipper’ largely hides from sight in the green and white fused sepals. The petals are also green and white, while the upper sepal is white with dark green striping. 12) P. insigne COMMON NAME(S): splendid paphiopedilum HARDINESS RATING: H1A FLOWERS: gold and yellow FLOWERING SEASON(S): autumn / winter / spring SIZE: 0.1-0.5m in height, 0.1-0.5m spread “Paphiopedilum orchids are a little tricky to grow but come in a wonderful array of colours, look extremely exotic and are one of only a few orchid types that cannot be mass-produced,” says Malcolm Moodie from the Solihull & District Orchid Society. The splendid paphiopedilum is an evergreen semi-terrestrial orchid. It has long, narrow, pale green leaves in a rosette form that are around 20-30 cm in length and solo flowers appear from the centre of the rosette. These flowers are on upright stems that are 15-30cm long and, like other slipper orchids, they have flowers with a pouch that traps insects and allows for pollination. The petals are yellowy-bronze and the upper sepal is yellow with red spots with a white upper margin. 13) P. ‘Leeanum’ COMMON NAME(S): slipper orchid ‘leeanum’ HARDINESS RATING: H1B FLOWERS: green, white and red FLOWERING SEASON(S): winter / spring SIZE: 0.1-0.5m in height, 0.1-0.5m spread Another slipper orchid to consider, this option grows around 30cm tall. It has single flowers borne on long stems in winter and early spring that can sometimes appear during other seasons when grown indoors or in a greenhouse. The flowers are 10cm wide, with a dark reddish-brown pouch, pale green-yellow petals with burgundy markings and an upper sepal that is pale green with burgundy speckles, fading into white at the top. 14) P. ‘Pinocchio’ COMMON NAME(S): venus slipper orchid ‘Pinocchio’ HARDINESS RATING: H1A FLOWERS: green, pink and yellow FLOWERING SEASON(S): spring / summer / autumn SIZE: 0.1-0.5m in height, 0.1-0.5m spread The Venus slipper orchid is a hybrid made by crossing P. glaucophyllum and P. primulinum. The flowers, borne successionally, can appear on the plants and remain in bloom over several months. They are borne on single spikes and have pink pouches, whitish green side petals with burgundy markings and a lime green sepal up top. 15) Phalaenopsis amabilis COMMON NAME(S): moth orchid / East Indian butterfly plant HARDINESS RATING: H1A FLOWERS: white FLOWERING SEASON(S): SIZE: 0.5-1m in height, 0.1-0.5m spread Now we turn our attention to the popular moth orchids that you might grow. Sometimes referred to as the East Indian butterfly plant, Phalaenopsis amabilis has fleshy, ovoid leaves up to around 50cm long and, from autumn to early spring, bears long-lasting and nicely scented white blooms up to 10cm across on stems that can be up to 1m tall. Grow indoors in a bright location out of direct sunlight in a spot that receives consistently warm and even temperatures. 16) P. ‘Dover’ COMMON NAME(S): moth orchid ‘dover’ HARDINESS RATING: H1A FLOWERS: white FLOWERING SEASON(S): spring / summer / autumn / winter SIZE: 0.1-0.5m in height, 0.1-0.5m spread This upright, epiphytic moth orchid is an abundantly flowering hybrid option, often producing three flowering stems, around 30cm tall, at the same time. The flowers are large and white, with mauve colouration at the throat and a yellow lip. Grow in well-drained neutral soil, ideally with temperatures of around 17°C at night and 20-25°C during the day. 17) P. ‘Picasso’ COMMON NAME(S): moth orchid ‘Picasso’ HARDINESS RATING: H1A FLOWERS: pink and white FLOWERING SEASON(S): spring / summer / autumn / winter SIZE: 0.1-1m in height, 0.1-0.5m spread Another upright-growing epiphytic orchid, this option often also bears a couple of flowers at the same time, each flowering stem growing around 60cm in height. The flowers are interesting, being of a harlequin type, and no two flowers are exactly identical. However, they are broadly white with a dark burgundy heart and scattered burgundy spotting, a burgundy-orange lip and a whitish-yellow edge on the side lobes. 18) P. ‘Sunshine’ COMMON NAME(S): moth orchid ‘sunshine’ HARDINESS RATING: H1A FLOWERS: yellow and orange FLOWERING SEASON(S): spring / summer / autumn / winter SIZE: 0.1-0.5m in height, 0.1-0.5m spread This is an upright and relatively compact orchid that grows around 30cm tall. It has long-lasting blooms which are mostly yellow in hue, with maroon freckles scattered across them and an orange lip. These orchids can also thrive in warm, even temperatures in bright but indirect light. 19) P. ‘White Apple’ COMMON NAME(S): moth orchid ‘white apple’ HARDINESS RATING: H1A FLOWERS: white FLOWERING SEASON(S): spring / summer / autumn / winter SIZE: 0.1-0.5m in height, 0.1-0.5m spread Another upright, epiphytic orchid, this one has ovoid, dark green leaves that are 15cm long and numerous long-lasting flowers on semi-pendulous branched racemes around 30cm in length. Each flowering stem carries around 15 flowers which open in succession. These blooms are white with a blush of pink and some mauve on the reverse side. The lip is yellowish and spotted in the centre. 20) P. ‘Yellow Lightning’ COMMON NAME(S): moth orchid ‘yellow lightning’ HARDINESS RATING: H1A FLOWERS: yellow and red FLOWERING SEASON(S): spring / summer / autumn / winter SIZE: 0.1-0.5m in height, 0.1-0.5m spread This moth orchid has broadly oval leaves and arching stems which boast a series of yellow flowers that have reddish tips towards the edges and purple at their centres. These flowers bloom over a long period and can appear at any time of the year.
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Orchid Nurseries Reveal The 6 Key Factors For Reblooming
IN THIS GUIDE 1) Create A Temperature Difference 2) Maintain Temperature Within A Set Range 3) A Deadheading & Pruning Regimen 4) Choose The Right Orchid 5) Find The Correct Sunlight Levels 6) Other Factors Orchids have won a reputation as ravishing flowering plants that put on a one-time extravaganza and then fail to rebloom. Well, I’m here to tell you that this bad rap is ill-deserved. The reason for failing to re-bloom is simple: these demanding plants have very particular needs and requirements, and if these go unmet, they will not rebloom. Very many factors come into play and it is the combination of these factors that influence reblooming. “The key to encouraging orchids to bloom is to focus on the fundamentals of their care,” says Daniel Toor, Owner of the specialist plant nursery The Dark Orchid. “By providing the appropriate amount of light, maintaining consistent temperatures throughout the year, and ensuring proper watering and humidity levels, you can help your orchids reach their full potential. “Often, part of the necessary environment can be naturally provided, making it easier to concentrate on meeting the other requirements. Simply put, following the basics of orchid care will help you achieve blooming success.” Underneath I lay out the various factors that influence whether an orchid reblooms or not, ordered from most important to not-quite-as-important: The temperature difference in the day versus the night. An orchid’s optimal temperature range. Deadheading and pruning regimes. Your choice of genus. The sunlight levels. Other, less common, factors such as humidity. 1) Create A Temperature Difference Just about all Orchid plants require a difference in daytime and nighttime temperatures to stimulate blooming. This is the single most important factor for reblooming. Nighttime temperatures need to be 5-10°C lower than daytime temperatures. Be aware that a required nighttime low for one genus could cause orchid plants of some other genus to die. For specifics please see the following section. Very broadly, daytime temperatures should remain between 21-27°C and nighttime temperatures between 14-20°C. Such temperature differences between day and night are not exactly easy for the hobbyist gardener to regulate. The most straightforward and trouble-free way to achieve the objective is to keep your orchids in a particular room where you can install a programmable thermostat. 2) Maintain Temperature Within A Set Range “The correct temperature range for the type of orchid will help your orchid to rebloom, as some cooler varieties will not flower if kept too warm,” shares Sara Rittershausen, the Owner of Burnham Nurseries. Orchids are divided into three categories depending on the optimal temperature range in which they will re-bloom: warm-growing, intermediate, and cool-growing. Warm-growing orchids need temperatures between 19-29°C during the day and 16-18°C during nighttime. These include Phalaenopsis orchids, most Paphiopedilums and most Vanda varieties. Intermediate-temperature orchids do best in temperatures typically between 21-25°C during the day and 13-15°C during the night. These types include Cattleya, Odontoglossum, some Miltonias, some Paphiopedilums and Brassavola. Cool-growing orchids are most comfortable in daytime temperatures of about 20°C through the day and only 10°C by night. The genera include Cymbidium, Dendrobium, Oncidium and most Miltonias. “Some species, such as Dendrobium lindleyi, need late autumn and early winter temperatures at the bottom of their range, with warmer temperatures to follow. This cooler, dry winter rest triggers flowering. 3) A Deadheading & Pruning Regimen Deadheading and pruning have significant impacts on re-blooming, for better and for worse, depending on what you do and to which orchid genus. This matter is perhaps the least straightforward and more of a judgement call for Phalaenopsis orchids and this is because, unlike all other orchid types, it may well rebloom from the same spike, even in the following season. In contrast, pruning is straightforward for Cymbidium. When you deadhead Phalaenopsis, you have a choice. Allow the flowers to fade and, when a faded flower can be twisted off, do so. Leaving behind the whole stalk in this way may result in fresh buds near the tip. Alternatively, trim the spike to just above the first node below the lowermost flower on the spike or to just above the second node from the base of the spike. This type of trimming may stimulate a branch from the trimmed spike. After the growing season has ended, if the spike has yellowed, it should be pruned, but if the spike has stayed green, it may bloom the following year, so there’s another judgement call! Paphiopedilum orchids ought to be deadheaded during the flowering season. After a flower has faded, cut its stalk a very small distance away from the spike, making sure that you do not injure the spike. Dendrobium orchid flowers may be deadheaded as they fade or you can wait until all of them on a spike are spent at which point the spike may be trimmed, but not from the base. Trim the spike some distance above the bulge, unless it has yellowed and shrivelled in which case you should prune the spike from the base. For Cymbidium and other types of orchids, prune the spike from the base after the plant has gone dormant. It may be hard to do so, but if you use mini-secateurs and use the bottom blade with which to hook the spike from the middle and slide the secateurs down the spike, you’ll get a clean cut from near the base. Whichever pruning implement you use, the blades should be sharp. 4) Choose The Right Orchid Some genera just bloom and re-bloom more readily than others, while others are known to be quite fussy. Oncostele, Phalaenopsis and Paphiopedilum orchids are all good at reblooming. Of course, there are other orchids that can rebloom, but the types identified here are the ones that will most reliably bloom again and again. 5) Find The Correct Sunlight Levels Information and opinions as to orchids’ light needs can be very conflicting and contradictory. One reason for this is that in different geographical regions, the strength and intensity of sunlight vary. A second reason is that, just as orchids are divided into three groups by temperature, they are divided into three groups by light needs, low-light, medium-light and high-light, and even this rule is somewhat generalisation. This considerable variance in light preferences is a natural outcome of the various native habitats of these plants, which range from open prairies and grasslands to low-light forests and bogs. Vanda, Brassavola, and Oncidium orchids all love 6-8 hours of direct sunlight every day, as do Cymbidium, Dendrobium, most Cattleya and some Epidendrum. Meeting these daylight requirements is especially important for most species in winter; this is when many species initiate their flower buds. During summer, however, avoid too much direct sun in the middle of the day for genera like Dendrobium – opting for a west-facing windowsill could be a good option. As for orchids with lower light preferences, 4-6 hours of sunlight is favoured by most Miltonias, whilst Paphiopedilum and Ludisia types prefer 2-4 hours a day. With these orchids, the light should also be less intense. Phalaenopsis is difficult to classify because these orchids’ light needs vary by variety and by the type of light they receive. Depending on these variables, moth orchids may be placed in any of the three categories. Some growers recommend shorter bursts of bright, indirect light, and others favour longer durations of less intense light. The exposure should be east-facing, otherwise east-facing to south-facing. In general, orchids should be placed in indirect sunlight that is dappled, filtered or diffused. You can also place orchids under grow lights where intensities and durations are controllable. “If your orchid is reluctant to re-flower, give it a holiday!” adds Mark Riley, the Technical Manager at Love Orchids. “Moving your plant to a brighter, cooler position in the house could be just what it needs to encourage a new flowering response.” 6) Other Factors Humidity and seasonal temperature variation also have an effect on whether an orchid reblooms. All orchids will be comfortable with a humidity between 50-60%. However, Paphiopedilum and Odontoglossum will be happiest with humidity nearer 70%. Orchid pots should be placed on orchid humidity trays; a humidifier is a very useful accessory if you grow orchids. Orchid dormancy periods differ from genus to genus, but they are all dormant during the winter. During dormancy, the day and night temperature levels should be kept about 5°C lower than the growing season levels. “Orchids also need correct nutrition to flower well,” adds Peter Lickorish, a Master Horticulturist. “Too much nitrogen later in the season and not enough potassium could hinder flowering, so check the N:P:K (Nitrogen:Phosphorus:Potassium) ratios in liquid feeds used.”
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Feeding Orchids: 'Use A Good Fertiliser That Does Not Contain Urea' Says Society Chairman
IN THIS GUIDE The Wrong Growing Medium Repotting Considerations Feeding Your Orchid Periodic Flushing References Orchids, so often mistakenly considered native to a particular type of tropical ecology, grow in an incredibly diverse array of ecologies and regions. Though a very large number of species are found in cloud forests, such as those of Costa Rica (whose national flower happens to be an orchid), these plants grow in the sparse ground at sea level, on treetops in rainforests and everything in between.1 Perhaps this is not too surprising because the Orchid Family includes 850 genera and nearly 30,000 species.2 So how do you set down fertilising and feeding guidelines for such a diverse plant family? Ifs and buts out of the way, please bear in mind that what follows are general guidelines that are suitable for most orchid varieties grown by hobbyist gardeners. However, other factors will certainly influence how well or how poorly your orchid plants respond to fertilising, as laid out below. Difficulty Easy Equipment Required Low-nitrogen, high-potash formula or a balanced formula When To Feed Once a week in the flowering season, every 20 days in the off-season The Wrong Growing Medium Before going into the particulars of feeding orchids, I need to cover a necessary preliminary: the growing medium. If you have obtained your orchid plant from a professional grower or an established nursery, you can skip this section, but if your orchid was purchased from a supermarket’s plant department or from your corner garden centre, read on. Purely commercial operations may or may not root a plant in the most suitable type of medium. For the large majority of plants, this horticultural inexactitude does not matter much and a multi-purpose compost usually works out fine. This is not the case for orchids. First off, free-draining medium is a non-negotiable for these plants. Any waterlogging or constant damp can bring about root rot. Next, these unusual plants by far prefer to be rooted in poor, low-nutrient media, though at the same time, they respond wonderfully well to regular feeding! So, if your orchid plant came from a garden centre or a supermarket, I’d suggest you play it safe and re-pot it in a suitable medium. Repotting Considerations Do not repot an orchid plant when it is in bloom, which will almost surely be the case when you buy it. Wait until it has finished flowering or until spring when fresh growth is emerging. In other words, repot your orchid when it is in active growth but not during its flowering season or during winter dormancy. You can purchase a specialised medium such as Westland Orchid Potting Mix or Miracle-Gro Orchid Potting Mix or you can make your own. A good medium for a potted orchid would be composed of fir bark, perlite and sphagnum moss. Other components that could be added or used as substitutes include grit, pine bark and peat moss. Grit may be needed to give stability to stop top-heavy pots from falling over. In what proportions, though? Actually, the ideal composition varies from genus to genus but you can’t go wrong with a basic mix of 3 parts fir bark, 2 parts perlite and 1 part sphagnum moss. Feeding Your Orchid Perhaps it is somewhat counter-intuitive that a plant that prefers poorish soil benefits greatly from some serious feeding. However, the style of feeding plays a key part. What these plants respond very well to is frequent feeding but in small doses. “Use a good fertiliser that does not contain urea and has many macro and micronutrients needed for orchids,” Malcolm Moodie from the Solihull & District Orchid Society shares. Also, feeding should be done for all twelve months of the year. However, the formula and frequency of the fertiliser that is used differs depending on the season, as Malcolm explains: “Regular feeding using a balanced feed or slightly higher nitrogen feed (Grow Formula) in the summer with a low Nitrogen feed (Bloom Formula) in winter will help.” So in the off-season, use a balanced formula, such as a 20-20-20 once every 20 days. During the blooming season, opt for a low-nitrogen, high-potash formula, such as a 10-20-30, and apply it once every 20 days from winter, increasing to once a week during peak flowering. Use the first type from the time the blooming season winds up until you see the first flowering stalk or the first bud. Then, switch to the second type and use it through the blooming season. Typically, these timeframes will run from sometime in October to sometime in March and vice versa. Feed when you water by adding in the fertiliser and applying in the same way you would water. “Misting water, mixed with fertiliser, to the underside of orchid leaves enables it to be taken in through stomata pores,” shares Peter Lickorish, a Master Horticulturist. “I find a mixture of foliar feeding in this way, and applying fertiliser to the medium and the roots through a watering can with a narrow spout, not a rose, is ideal.” How much fertiliser you use depends on various factors, including the age and size of the orchid plant and the size of the pot. Do not feed an orchid plant at all in its first year. We recommend that you use about 75% of the concentration or volume recommended by the manufacturer. Apply at a lower concentration during winter. Use a liquid formula or make your own liquid using powdered fertiliser, but remember to use rainwater or distilled water. Periodic Flushing It is possible for salts to build up in the growing medium. Therefore, twice in the off-season and twice during the blooming season, skip a scheduled feeding and, instead, drench the medium, allowing the water to flow out from the drainage holes, so as to flush out any built-up salts. Such flushing is critical for some genera that are intolerant of salts build-up, such as pansy orchids. Resume watering and feeding as usual promptly after (but only after) the medium has dried out. References 1. Orchids of the Cloud Forest. (n.d.). Cloudbridge Nature Reserve. Retrieved April 20, 2023, from https://www.cloudbridge.org/wp-content/uploads/2011/11/NatureNotesNo15.pdf 2. Johnston, E. (2022, February 28). Exploring the orchid family tree. Kew Royal Botanic Gardens. Retrieved April 20, 2023, from https://www.kew.org/read-and-watch/orchid-family-tree
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