Growing
Pruning Won't Benefit Juniper Directly - But It Can Help Maintain Its Shape Or Training
IN THIS GUIDE Do You Need To Prune Juniper? When To Prune Juniper Avoid Cutting Away Too Much Growth Juniper can be a dependable choice for many UK gardens and there are a plethora of options when it comes to size, shape and form. There are junipers to grow as trees, some that can remain taller shrubs and others with prostrate form. Junipers are generally low-maintenance plants when placed in the right location. And even when it comes to maintenance jobs like pruning, less is more. Do You Need To Prune Juniper? There is debate as to whether or not this is a job that we need to undertake at all. In many cases, pruning is important because it helps the plants that we grow by keeping them in optimal health. However, with juniper, pruning will not benefit the plant itself. These are shrubs or trees that naturally form a well-shaped framework of branches and they do not need pruning to grow well. What’s more, they grow slowly, so pruning can set them back unnecessarily. That said, while we do not need to prune juniper, sometimes we may choose to do so to maintain a certain shape, train it into topiary forms or for aesthetic reasons. When To Prune Juniper If you do decide to prune a juniper, the best time to do so is in the early spring, after the coldest weather and before tender new growth emerges. Remember, pruning is typically not needed at all, but when you do wish to prune for aesthetic reasons, this is typically the time at which it will have the least impact on your plant. Avoid Cutting Away Too Much Growth If you do decide to prune juniper because you are shaping some topiary or wish to keep your juniper in check, the process is simple. Be circumspect and keep in mind that the fewer cuts you make, the better. The key thing to remember when pruning juniper is that new growth will not emerge from older wood where there are no needles at all, so do not prune back beyond the point where needles form on the green tips of branches unless you are removing an entire branch. You can remove entire branches for aesthetic effect and should also remove any dead or damaged branches which have no needles on at all, since, as mentioned above, these will not produce new growth. Use a pair of secateurs to remove individual portions of the juniper, rather than giving it an all-over shearing. Don’t take too much from the plant and never prune out more than a quarter in a given year or it will not recover. Remember, junipers are shapely and slow-growing, so even when you do decide to prune and form a juniper into a specific shape, you should be very careful about where you cut and how much material you take.
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Cleome ‘Spider Flowers’: Try Growing These Plants In Ornamental Borders
IN THIS GUIDE Overview Common Varieties How To Grow Spider Flowers Growing From Seed Cleome Plant Care References ‘Spider Flowers’ are popular annuals to grow in ornamental borders to add height and colour over the summer months. Cleome is an annual that grows tall with unique, distinctive flower heads made up of small individual flowers that look like spiders or whiskers. These plants are native to parts of South America.1 Overview Botanical Name Cleome hassleriana Common Name(s) Spider flower, pink queen, grandfather’s whiskers Plant Type Annual Native Area South America Hardiness Rating H2 Foliage Deciduous Flowers Racemes of flowers with 4 petals and conspicuous stamens in purple, pink or white When To Plant Out May to June This plant tends to grow tall, around 1.5m in height, and its flowers come in purples, pinks and white. A half-hardy annual in temperate climes, spider flowers are used to fill gaps in warm and sunny summer borders, but will not typically survive colder conditions. Common Varieties There are several different well-known varieties of Cleome to consider for gardens in the UK. There is a well-known series known as the ‘Queen’ series with cultivars in different colours, such as ‘Violet Queen’, ‘Rose Queen’ and ‘White Queen’. ‘Violet Queen’ I’d also recommend a cultivar named ‘Helen Campbell’, which has white blooms and is another that is highly regarded, having been awarded an Award of Garden Merit from the RHS. How To Grow Spider Flowers Cleome is relatively easy to grow as long as it is provided with the conditions that it requires to grow well. One of the key things to remember is that this is a half-hardy annual that cannot cope with colder conditions and it is therefore a plant which will be in your garden only over the warmest part of the year. You also need to make sure that spider flowers get plenty of sun and, as tall plants, they should be placed in a sheltered position so that they do not get blown over. “They fit well into a cottage garden planting scheme towards the back of a border, with lower-growing plants such as Dianthus (Pinks), Aquilegia and Geranium in front and perhaps in between Digitalis (Foxglove) of a similar height,” shares Master Horticulturist Roy Nicol. Hardiness Cleome are half-hardy, so cannot cope with colder conditions. They will do fine outside in a UK garden over the summer months, but they will not cope with freezing conditions and won’t overwinter in a garden. As annuals, they will be removed after flowering and won’t live for a second year. Soil Requirements Cleome likes moist but free-draining or free-draining soil. It will grow best in free-draining sandy soil or another medium that drains well, but is unfussy when it comes to pH levels. Growing From Seed Cleome hassleriana seeds can be sown indoors in March for planting out in May or June once the weather where you live has warmed reliably. Sow the seeds in a heated propagator or with bottom heat on a bright windowsill indoors for the best germination rates. Prick out seedlings into individual pots or soil blocks once they are large enough to handle and grow on indoors or under cover until the weather is warm enough to plant outside in the garden. Remember to harden off your indoor sown plants before you place them out into their final growing positions. Cold Stratification Whether or not Cleome seeds need a period of cold before germination is a matter of some debate. Some simply sow the seeds without giving them a period of cold stratification. However, some experienced growers argue that it is best to place the seeds in the fridge for a week before you sow them. Germination can be tricky, so to give the seeds the best chance of germinating, it is important to provide the ideal conditions for them. This means sowing indoors, where you can give reliably warm temperatures. It also means sowing on the surface or covering only lightly, so the seeds get the light they need to germinate too. Another tip that gardeners have come up with is to create fluctuating temperatures by either placing them in a greenhouse for cold nights and warm days or by placing them on a windowsill indoors, then placing them out in the cold for a few nights. One other thing to note when growing Cleome from seed is that you should not give up on them too early. I have known it to take 5-6 weeks before the seeds germinate successfully. Cleome Plant Care When it comes to caring for Cleome, choosing the right growing position is a big part of the puzzle. As long as you have positioned these plants correctly, you should generally find them relatively easy to grow. The simple tasks of watering, deadheading and feeding are really the main jobs to think about when growing spider flowers in your garden. Watering Cleome should be watered in well upon planting it out and kept well-watered during establishment, especially for the first couple of weeks. Thereafter, it will usually only need to be watered during dry spells, when it should be watered regularly. Pruning The only pruning or cutting that you have to think about when growing Cleome is deadheading. Cutting off spent flower heads will encourage the plant to focus on producing further blooms, which can prolong the flowering period. If you deadhead, you may be able to enjoy Cleome blooms from July through to September. After flowering, the whole plant will be removed as this is an annual which will complete its lifecycle in a single year. Fertilising It is best to encourage blooming by feeding Cleomes with a liquid organic plant feed that is high in potassium every couple of weeks throughout the summer months, while the plant is in bloom. A feed that is homemade, like comfrey tea, can be ideal for the purpose. Common Problems Look out for slugs and snails when the plants are young. Encourage biodiversity in your garden so the population of these pests does not get out of control and use physical barriers to protect young plants where necessary. Cleomes may also have a problem with cabbage white butterflies in summer, just like brassica crops, to which they are related. Nasturtiums can be a useful trap crop for these garden pests and can help to keep your Cleomes safe. Self-Seeding Cleome can self-seed in some climates, even to the point of becoming invasive. However, this does not typically happen here in the UK. Germination rates can be poor without warm conditions, so it is best not to rely on self-seeding if you want to grow this plant again the following year. I’d argue it’s also best to deadhead rather than letting these plants set seed because if you deadhead, the plants can focus on further flowering and you will have blooms into early autumn and – in more southern areas – even right up until the first frost. References 1. Susan.Mahr. (n.d.). Spider flower. Wisconsin Horticulture. Retrieved June 9, 2023, from https://hort.extension.wisc.edu/articles/spider-flower-cleome-hassleriana/
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Leaves On Your Kentia Palm Turning Brown? It's Probably One Of These Four Issues
IN THIS GUIDE 1) Low Humidity, Low Temperatures Or Underwatering 2) Overwatering Or Waterlogged Soil 3) Sun Scorch 4) Scale Insect Damage Kentia Palms are popular houseplants to grow inside a home. As long as they are provided with the right environmental conditions and care, they are relatively easy and forgiving plants to grow. However, as with most plants, brown leaves are a sign that something is not right – but determining what precisely is wrong can be a little more challenging. If you see brown leaves on your Kentia Palm, this might be caused by a number of different factors, including: Low humidity, low temperatures or underwatering. Overwatering or waterlogged conditions. Sunburn caused by over-exposure to the sun. An infestation of scale insects. Note that brown fronds at the base are perfectly normal for Kentia palms and you can simply cut these away. It is only when the brown colour is found all over or beyond just the base that this is likely to suggest a problem. 1) Low Humidity, Low Temperatures Or Underwatering If there are dried, brown tips on the leaves of your Kentia Palm – which I find is a common complaint – this can be due to several different issues with the environmental conditions or care. It might be a sign that the humidity is too low. If this is the case, try moving the plant to a more humid spot, perhaps close to other houseplants, away from any drying heat source. A bright bathroom can be the perfect spot, as it will be humid if used regularly for bathing or showers. Elsewhere in your home, regular misting of the plant will commonly be required. Brown leaf tips could also be a sign that the temperatures have dropped too low. Remember that these plants have a hardiness rating of H1A and need temperatures to remain above 15°C. Often, this is a problem that can indicate that you’ve not watered your Kentia Palm enough. In my experience, brown leaves happen most often when I have not been diligent with my watering duties during the warmer months of the year. I usually find that if you resume watering when the top few centimetres of the growing medium are dry, the plant should recover. You can, if you wish, cut off the brown sections, but do not cut into the green as new brown tips will simply develop if you do so. 2) Overwatering Or Waterlogged Soil Some brown fronds at the base are normal, but if there are more widespread brown leaves, this can be a sign that there is a problem with overwatering or waterlogging. Unfortunately, in waterlogged conditions, root rot is likely to set in. Removing damaged root sections before repotting may sometimes allow your plant to recover if the problem has not been allowed to progress for too long. This of course means that you will need to amend your watering routine with the unaffected section of the plant. 3) Sun Scorch If whole leaves on your Kentia Palm are not turning brown and you are seeing isolated brown patches on the upper leaves of the plant instead, this is more likely to be sunburn. If your plant is in direct light during hot sunny days, it may get scorched through the glass. Move your plant so that it is still in a relatively bright location but out of direct sunlight, especially during the hottest part of the day. 4) Scale Insect Damage Finally, if you see brown dots on Kentia palm leaves, look closer. You might actually see that those brown spots are scale insects. Scale insects are a common houseplant pest that can be a problem when growing Kentia Palms, but you can wipe them off with an organic insecticide if they become a problem. Of course, the problems listed above are just some of the most common reasons for brown leaves on a Kentia Palm and other issues might also arise. Still, when trying to work out what is wrong, looking at the basic environmental conditions and elements of care first is a good place to start, as more often than not, this is where the problem will lie.
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Unhappy Ficus Plant? Here Are 5 Reasons For Drooping Or Yellowing Leaves
IN THIS GUIDE 1) A Lack Of Light 2) Temperature Issues 3) Environment Changes Or Root Disturbance 4) Overwatering Or Waterlogging 5) Pest Problems Ficus benjamina can be a beautifully elegant and relatively easy houseplant to grow. However, it can be fussy if the basics are not in place and it is not cared for correctly. And in my experience, it is quick to let you know when it is not happy. A wide range of different stressors can cause leaves to turn yellow and drop off. Some of the most likely causes of drooping or yellowing leaves on a Ficus bejamina are: A lack of light or sudden changes in the amount of light. Temperatures that are too high or too low. Changes to the environment or root disturbance. Overwatering or waterlogging. Underwatering during warmer months can also be a common cause. Pest problems like mealybugs or scale. We share more insight into each of these problems and solutions for each below. 1) A Lack Of Light The first reason that a weeping fig might start dropping its leaves is that it is located in too dim or shaded a location. These are plants that require bright but indirect light within a home. They cannot thrive in a very dark situation. These plants are also prone to experiencing stress when there is a sudden change in the environmental conditions. A change in the light levels is one change that can spark off stress in the weeping fig plant. 2) Temperature Issues Sudden changes in temperatures can also cause leaves on a weeping fig to fall. Temperatures that fluctuate too extremely, those that are too high and that are too low can all cause stress and lead to this problem. Careful placement of a weeping fig in the first place is very important. You need to choose a location that is not in a draught or too close to a heat source such as an oven, stove or radiator. These houseplants need temperatures to remain consistently at around 16°C and will suffer if the temperatures fluctuate much from this. The temperatures should remain above 13°C, even through the winter months and will usually die if temperatures drop below 10°C. 3) Environment Changes Or Root Disturbance Weeping figs can be low-maintenance when they are in the right place with the right conditions, but it is important to remember that they are intolerant of changes. When first potted up into a new container or when repotted, they can lose some of their leaves due to the stress. They may settle down over time as long as the conditions they require have been provided, but you should always take care to disturb or move one of these houseplants as little as possible. 4) Overwatering Or Waterlogging Sometimes, leaf fall or yellowing leaves on a weeping fig plant may be due to a problem with excessive watering or poor drainage. These plants require a growing medium that is moist yet free-draining. The top few centimetres of the growing medium should feel dry before you water it once more and when watering, excess water should always be allowed to drain away freely. Yellowing leaves and leaf drop can be a sign of overwatering or waterlogging and potentially indicate a problem with root rot if this issue has been allowed to persist. If you feel as though you may have been neglecting the regular watering schedule required for a Ficus, this may also be the cause – especially if the plant is showing these signs during warmer months. 5) Pest Problems Since dropping leaves on a Weeping Fig are typically a sign of stress of some kind, this problem can also be caused by a pest infestation. When growing indoors, these plants can be plagued by many common houseplant pests, such as mealybugs, scale insects or red spider mites. Severe infestations can sometimes lead to defoliation. While there are other issues that can potentially cause both leaf drop and yellowing leaves on a Ficus benjamina, ruling out the above is typically the best place to begin when trying to solve the problem. Often, with the root cause removed or remedied, the plant will be able to recover.
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Caring For A Ficus Benjamina Houseplant - These Plants Are Tolerant Of Neglect
IN THIS GUIDE Overview Common Types Weeping Fig Care Ficus benjamina, also known as the ‘Weeping Fig’, ‘Java Fig’ or ‘Java Tree’, is a popular houseplant. It can be placed outside in summer in a mild and sheltered position, but it is commonly grown indoors year-round. It is highly prized as a houseplant for its elegant form and glossy green leaves. Overview Botanical Name Ficus benjamina Common Name(s) Weeping Fig / Java Fig / Java Tree Plant Type Houseplant / Tree / Shrub Native Area Southeast Asia and Australia Hardiness Rating H1C Foliage Evergreen Flowers Inconspicuous, followed by reddish-orange fruits which turn black When To Plant May to September When To Prune January to March With the right care, this plant can look seriously impressive and bring a taste of the tropics to a home. It also has a tolerance for relatively poor growing conditions, making it a good choice for those who are not necessarily the most green-fingered of people and for those looking for a relatively low-maintenance houseplant that won’t be too fussy to grow. Common Types As well as growing the species type Ficus benjamina, which has received an Award of Garden Merit from the RHS, you can also consider a variegated version with white variegation on the leaves. The variegated cultivar ‘Starlight’ has also been given an Award of Garden Merit. There are also compact cultivars to choose from if space is limited. ‘Too Little’, for example, is popular with bonsai enthusiasts. Weeping Fig Care Caring for a weeping fig is relatively simple as the plants are tolerant of a lot. However, there are certain things that you do need to provide to grow these plants successfully, since not getting the basics right means that these plants can lose their leaves. Below are the main things to think about. Light & Temperature Outdoors, where they can be placed in the summer, weeping figs require full sun to partial shade. Indoors, where they are often kept, they will do well in a south or west-facing window, in bright but filtered light. These plants can cope with temperatures of 5-10°C but not below and will not survive in freezing conditions. A steady temperature of 16°C is ideal – which is why these plants are generally grown indoors or only placed outside in summer. Preferred Soil These plants need humus-rich soil which is moist yet free-draining. A loam-based potting mix that is peat-free is generally considered to be the ideal growing medium when you are growing a Ficus benjamina indoors in a container. Watering Ficus benjamina will require regular watering, but it is also important not to overwater and to let the growing medium dry out somewhat between waterings. Water deeply when the top few centimetres of the growing medium feel dry to the touch. I would implore you to water well but to make sure that excess water can drain away freely. I tend to find that if I am a neglectful plant parent and forget to water my Ficus regularly, this is a plant that is quite good at letting you know it is unhappy – often by wilting, turning yellow and dropping leaves. Curtail watering, but do not stop entirely, during the winter months. Feeding During the spring and summer months, it is best to feed weeping figs with an organic, balanced liquid plant feed every couple of weeks. I find that a seaweed feed is ideal, but feed only occasionally during the coldest part of the year. Pruning Ficus benjamina is in RHS Pruning Group 1 and has a naturally well-balanced framework of branches and a pleasing shape – so they don’t necessarily need pruning to keep them in shape. Light maintenance pruning is all that will ever be required when growing these plants and even that light pruning is not always required. In late winter or early in the spring, check the plants over and if there is any damaged, diseased or dead material, this can be pruned out. You can trim branches that are crossing or overly congested too if you wish. Repotting It is not ideal to repot a Ficus benjamina too frequently. These plants can have a tendency to drop their leaves in response to environmental change, which includes being moved to a new pot. If they really need it, young weeping fig plants can be repotted into a slightly larger pot in the spring. Once they are larger and more established, it is best to keep the same pot. You can, however, replenish any nutrients by adding a top layer of compost in the existing pot each spring. Overwintering When a Ficus benjamina has been placed outside during the summer, it will need to be brought back indoors or undercover before temperatures drop below 13°C to avoid any issues. Remember to reduce watering and feeding over the winter months and keep temperatures to 13°C or above at all times during the coldest part of the year. Propagating Ficus benjamina can be propagated by means of seed or cuttings. Leaf buds or semi-hardwood cuttings can be taken to grow on and become new plants to add to your houseplant collection. Common Problems Like other houseplants, weeping figs can get infested with pests such as scale insects, mealybugs, thrips and red spider mites. But most of the issues that occur when growing these plants arise because of a problem with the environmental conditions or because of a sudden change in the environment. If you do notice your plant ‘acting up’, I’d generally advise you to look at light exposure and watering in the first instance.
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Beware The Giant Himalayan Lily - These Plants Are A Lot Of Work For Little Reward
IN THIS GUIDE Overview Common Types How To Grow Himalayan Lily Cardiocrinum Care References Cardiocrinum giganteum, the Giant Himalayan Lily, is a flamboyant and dramatic plant to consider growing in your garden. Though not widely known, this plant is an attractive show-stopper that grows slowly but is well worth the wait. Cardiocrinum is a genus of bulbs in the Lily family, of which the giant Himalayan Lily is the largest, growing up to around 2.5m tall.1 These are monocarpic perennials, which, though they can live for a number of years, will die after flowering. This can mean that these plants take an awful lot of work for such a short flowering window – and I would say this is the main thing to bear in mind when choosing to grow these plants. Overview Botanical Name Cardiocrinum giganteum Common Name(s) Giant Himalayan Lily Plant Type Monocarpic Perennial Native Area South to Central Asia Hardiness Rating H5 Foliage Deciduous Flowers Trumpet-shaped flowers like lilies When To Plant February to July The flowers of this plant are prized for their appearance and fragrance and bloom on mature plants sometime between June and August. These trumpet-shaped, lily-like flowers are followed by oblong seed pods that can be kept and dried and used in floral arrangements inside a home. Common Types Cardiocrinum has three species – Cardiocrinum cathayanum, C. cordatum, and C. giganteum, the latter of which is the species most commonly cultivated in a horticultural setting. There are two main varieties of C. giganteum: C. giganteum var. giganteum – up to 3m tall with greenish flowers that are streaked with purple on the inside. C. giganteum var. yunnanense – up to 1-2m tall, with white flowers streaked with purple-red on the inside. How To Grow Himalayan Lily Himalayan lilies are not necessarily the best choice if you have an impatient streak, but growing them successfully and seeing their flowers after your wait can be worthwhile. Sowing These plants typically take 7 years to reach flowering size from seed and they will die after they flower. However, as they grow, the plants will produce bulblets at the base which can be used for propagation. The bulblets will then typically take between 3-5 years to bloom. Since using the bulblets to propagate the plant results in blooms somewhat more quickly, this is often the method used, but these plants can also be grown from seed by very patient gardeners. The seed is best sown in a cold frame or other protected spot in the autumn, as soon as it becomes ripe. Seeds may germinate the following spring but it can take up to 2 years for the seeds to germinate. You will then need to grow on the plants in a protected area such as a greenhouse, polytunnel or cold frame for 3-4 years before you plant them out into their final growing position in the garden. Preferred Sunlight These plants do best in partial shade and will thrive if given woodland conditions similar to those of its native habitat. They don’t like frost pockets or particularly chilly spots, where they may need some additional protection through winter. Equally, they will not do well in a particularly parched, hot and sunny spot, so finding the right balance when it comes to light levels and temperatures can be important. Soil Requirements The soil must be moist yet free-draining and ideally deep, humus-rich and fertile. The specific soil type and pH do not matter too much as these plants can actually cope in a wide range of very different areas. Planting Giant Himalayan lilies are best planted out in spring or autumn, depending on their size and stage of growth. Before planting, be sure to prepare the area well and provide plenty of organic matter to ensure a fertile and humus-rich medium. When planting, the bulb should be lightly covered with leaf mould if possible. Cardiocrinum Care Caring for these large and dramatic bulbs means making sure that you continue to meet their environmental needs over time. Watering Water well during dry spells to maintain soil moisture, but take care not to saturate the site and make sure that excess water can drain away from the planting location freely, even in heavy rainfall conditions. Fertilising Replenish the mulch around the plants each spring and add additional mulch materials in summer to meet the fertility needs of your plants. Propagation As mentioned above, these plants can be grown from seed, but are more commonly grown from the bulblets which are separated from the base of the old plant after it flowers. Overwintering Cardiocrinum giganteum is H5 hardy and can cope with winter conditions throughout most of the UK, even during extreme cold. However, you do need to look out for winter wet, which can cause a number of problems if waterlogging is allowed to occur. You also need to be aware of pests like slugs, mice and voles, which can be attracted to the bulbs and cause damage to them, especially during the colder months of the year. Common Problems Aside from slugs, mice and voles which can cause damage to the bulbs, you will also need to remain vigilant for a number of other problems that can arise when growing these plants. “In particular, as these plants are members of the Lily family, they are susceptible to lily beetle, a small scarlet red beetle which consumes the foliage and flowers of the plant,” shares Master Horticulturist Roy Nicol. “They are best picked off and squished. Be careful not to allow them to employ their defence mechanism where they drop to the ground and become lost in the foliage of plants.” Most of the issues that can arise do so because of problems with the environmental conditions or care. References 1. Cardiocrinum giganteum. (n.d.). Royal Horticultural Society. Retrieved December 4, 2023, from https://www.rhs.org.uk/plants/297145/cardiocrinum-giganteum-from-sikkim/details
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Pruning Deutzia Like This Makes A Huge Difference To Plant Health And Longevity
IN THIS GUIDE Should I Prune My Deutzia Shrub? When To Prune Deutzia Maintenance Pruning Rebloom Pruning Rejuvenation Pruning Free-flowering Deutzias are the shrubs of choice for the one-minute gardener who wants to have it all. Over May and June, these plants can light up a garden with their charming little star-like blooms that range from bell-shaped to salver-shaped in whites and delicate shades and blushes of pink. Deutzia can be considered one of the best low-maintenance shrubs for which anything will do. However, all such shrubs have one or another point of care and for Deutzia, that point happens to be pruning. You don’t have to prune Deutzia, but correct pruning makes a great difference in the health and longevity of these shrubs, and can bring about a dramatic improvement in flowering. Difficulty Medium Equipment Required Gardening gloves, secateurs, pruning shears, bypass or anvil loppers When To Prune July Should I Prune My Deutzia Shrub? Deutzias differ greatly in their sizes and almost as much in their growth rates. Many varieties are well under 1m in height and spread while a few measure up to 3m tall and wide. Typically, the smaller varieties are bushy and mounded, while the bigger ones have gracefully arcing stems and are a little more open. Therefore, how you prune a Deutzia in its first or second year will depend on the variety. Also, depending on the variety, size, age and condition, you may be pruning anything from young green shoots to a thick woody branch or two. As such, you may need secateurs, pruning shears, bypass loppers or anvil loppers to complete this job. When To Prune Deutzia Deutzias are spring-blooming deciduous shrubs that flower on the previous season’s growth. This means that after a Deutzia is finished with blooming in early summer, it spends the rest of the growing season forming fresh growth that will bear the following spring’s blooms. Therefore, you should not prune this plant after this fresh growth emerges or you will be pruning away many of the following year’s flowers. So, the correct time to prune it is soon after flowering, which is usually around July here in the UK. Maintenance Pruning First, prune away dead and diseased stems at their attachments. Weak and spindly stems and shoots that bear few or no flowers should also be pruned. Finally, a stem growing crosswise against another should be pruned or trimmed. You can also conduct a type of tip pruning that will stimulate fresh flowering growth for the following season. Trim stems that have flowered by approximately one-half, no less than one-third and no more than two-thirds, trimming down to a set of strong and healthy side shoots. Pay special attention to old wood. These are stems that are woody, long and worn-looking with a very pronounced arc. “Each year one or two of these stems should be removed at the base (no more than 20% of the total number of stems) to encourage the growth of fresh stems which will flower the most strongly,” Roy Nicol, a Master Horticulturist, suggests. Similarly, you should also prune branches that did not produce flowers to maintain size and shape by removing them at the base. Water and feed the plant well after pruning. Rebloom Pruning Though it is highly irregular to mistreat Deutzias in the manner described here, try this trick if you’d like to tease your plant to produce a second flush of blooms out of season. Do not wait for the blooming season to end. Instead, when the blooming season is past its peak but still ongoing with around 10 more days to go, prune the shrub as described above. Water the plant well. Around 7-10 days later, feed the plant with a high-potash formula at only about 75% of the instructed strength and volume. Rejuvenation Pruning An overgrown and straggly Deutzia that has not been pruned and produces sparse flowers may be rejuvenated by a hard prune. This type of rejuvenation pruning is best done in early spring just when fresh growth emerges. Here, your aim is not to try to save the season’s flowers; it is to reboot the shrub to start it from scratch. If you do, you’ll sacrifice whatever flowers the shrub may bear during the current season to gain renewed flowering from the year after. Prune up to one-half of the stems and side shoots at their origins, then trim from one-half to one-third of the entire shrub, making each cut just above a node. Be sure to leave behind young branches and shoots and some emerging growth. About a week later, feed it with an all-purpose balanced fertiliser, using it at only 50% of the recommended strength and volume; applying it at a safe distance from the roots.
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Deutzia Can Be Grown To Fill Beds, Create Borders Or Plant On Slopes - Here's How
IN THIS GUIDE Overview How To Grow Deutzia Deutzia Plant Care Common Deutzia Varieties For an undemanding and no-fuss shrub, Deutzia is a gardener’s jackpot. It produces glorious arrays of charming star-like blooms in white and pinks, often fragrant or double form, over a backdrop of brilliant green picture book leaves. If you’re in the market for a low-slung, ornamental hedge, perhaps a bushy, mounding shrub will fit the bill. Deutzia is made to order for a hedge of the type described above as much as it is to fill beds, make borders, plant on slopes and verges and choose as a companion plant. Overview Botanical Name Deutzia Plant Type Perennial shrub Native Area China Hardiness Rating H5 Foliage Deciduous Flowers Small, five-petalled, star-like, bell-shaped, cup-shaped or salver-shaped, pendent or erect flowers borne in clusters When To Plant June or September These exceptionally pest-free and disease-resistant shrubs are very hardy at H5, have no positional requirements whatsoever and can make do in even a shady spot with poor-draining soil. But unlike many other no-fuss plants, this one bears flowers like there’s no tomorrow, racking up huge bloom counts across May and June. How To Grow Deutzia Planting Deutzias may be planted anytime from summer to mid-autumn, especially if you live in colder regions of the country, excluding any hot spells and rainy days. However, planting it in the milder months of June or September and avoiding the hot summer months will allow the plant to establish itself quicker. Because of the great diversity in garden Deutzia varieties, some will perform better in full sun and others in partial shade, but you can’t go wrong if you choose one or the other. They may be sited in any exposure but sheltered is preferable and as for aspect, simply avoid north-facing. Using the type of soil described underneath, prepare a planting hole about 1.5 times the width of the pot or root system. If it is a young plant, dip the roots in water and gently spread them out before planting, but if it is a mature plant, leave the soil ball as it is. Dip the roots with a soil ball in water but do not interfere with them. As you backfill the hole, dampen the soil and tamp it down, ensuring that the soil level is no higher than it was in the pot. Soil Requirements One of the several merits of these low-maintenance shrubs is their ability to thrive in any type of soil. However, to get the best out of these plants, take a mixed loam as a base and amend it by one-third of its volume with humus compost or other organic compost. Shovel in some grit and perlite to ensure good drainage. “As with most woody shrubs, in subsequent years I would recommend an annual mulch in a ‘doughnut ring’ around the base with good organic matter such as garden compost or rotted manure in the autumn,” shares Horticultural Consultant Roy Nicol. “This improves the soil structure over time and allows a good root run to access water and nutrients in the soil.” Container Growing You cannot make an overall generalisation about container growing where Deutzias are concerned because these woody shrubs differ so much in size. We suggest that varieties that are 2m or more in height and spread not be grown in containers. After all, there are quite a few varieties that are just perfect for pots. When you grow these shrubs in a container, choose a pot that is one size bigger than you would choose for a similarly sized shrub of some other genus. Deutzia Plant Care Watering & Feeding Though Deutzias are not bog plants nor are they drought-tolerant, established plants of various varieties can put up with both overwatering and poor-draining soil and with short dry spells. During the growing season, water the shrub deeply and allow the soil down to a few centimetres to become dry before watering again. In normal mild weather, watering once or twice a week, accounting for rain, should suffice. During the dormant season, after the plant has shed its leaves, water plants in pots infrequently so that the roots stay hydrated and do not dry out. Any high-quality all-purpose fertiliser applied annually upon the arrival of spring will bring forth healthy growth and blooms. Propagating Via Cuttings Though quite a few Deutzias can be propagated by both softwood and hardwood cuttings in different seasons, all can be propagated by softwood cuttings in the summer, with June being the best month. Prepare a small pot with cuttings compost. I like layering the media in a pot so that the cutting not only roots but can also grow and thrive in the same pot. To use this method, put pebbles and grit at the bottom, then readymade potting compost or a mix of organic compost and sand, with a final layer of perlite and sand with a touch of compost for the uppermost layer. Either way, moisten the medium. Water the plant well in the early morning, then cut an 8-10cm length from a softwood shoot. It should be green for most of its length and greyish-brown in the bottom section. Make the cut just below a node, then strip the lower leaves, retaining the upper two or three leaves. Dip the base to a third of its length in rooting hormone gel or in honey and cinnamon. Insert it to about a third of its length in the pot and moisten it. Common Problems Deutzias are uncommonly resistant to pests and diseases. The only problems you need to watch out for in the UK are aphids and honey fungus. While aphids are quite easily controlled, honey fungus is one of the most serious fungal infections which is hard to detect early and from which there is no recovery. Common Deutzia Varieties For a plant that is not exactly world famous, Deutzia encompasses quite an astonishing number of varieties in the form of crosses, hybrids and derivative cultivars, besides the many species. The selections offered underneath are chosen to reflect this diversity in lineage but are also amongst the prettiest, most popular and most readily-sourced varieties. D. gracilis Rising to almost 1m with a spread only a little smaller, the Japanese Snow Flower is aptly named for its star-like, salver-shaped, small flowers that are snow white. These delightfully fragrant blooms are held aloft in upright sprays. D. gracilis ‘Nikko’ Deutzia gracilis has very many cultivars of which ‘Nikko’ is one. Its flowers resemble those of the species plant but this compact cultivar rises to only 60cm with twice the spread. Its leaves put on shades of purple in the autumn and this cultivar has received the RHS Award of Garden Merit. D. scabra ‘Plena’ A tall variety reaching 2.5-3m with about half the spread, Deutzia scabra ‘Plena’ produces double-form white flowers whose outer petals often show a pinkish-purple tinge. The nodding flowers are borne on dense panicles. D. crenata ‘Pride Of Rochester’ Breaking the mould, ‘Pride of Rochester’ has small, double blooms that are white with decorative pink flushes on the petals appearing in highly varying degrees. It grows to about 2.5 metres and is another recipient of the RHS Award of Garden Merit. Deutzia pulchra Not only beautiful but big at about 2m tall, beautiful Deutzia lives up to its name. Its pendant panicles contain shy and demure little blooms that feature rich pink blushes on the white petals. D. × magnifica ‘Rubra’ This Deutzia justifies its various complimentary names, as it produces bigger-than-average, rosy flowers. Born in panicles, these blooms vary in colour from soft pink to pinkish-red with marvellous tonal gradations. It grows to about 2m tall and has received the RHS Award of Garden Merit. D. × elegantissima ‘Rosealind’ A compact variety at about 70cm tall with a spread of a little over 1m, the floriferous ‘Rosealind’ bears flowers in big, thick clusters. These little blooms are a classic candy pink to reddish-pink hue. It has achieved the RHS Award of Garden Merit.
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Horticulturists Share How To Grow Calceolaria 'Slipper Flower' And Some Common Types
IN THIS GUIDE Overview Common Types How To Grow Calceolaria Calceolaria Plant Care References Want to brighten up your garden with a flower that melds the cute with the exotic? Calceolaria, also known as the slipper flower, will do it in spades. This tender shrub produces incredibly charming little blooms that resemble a lady’s purse (another popular name for them) in warm hues. Overview Botanical Name Calceolaria integrifolia Common Name(s) Slipper Flower / Slipperwort / Pocketbook Plant / Lady’s Purse Plant Type Perennial Sub-Shrub Native Area Mexico, Chile & Argentina Hardiness Rating H2 Foliage Evergreen Flowers Ovoid, 1-1.2cm, shaped like a Dutch slipper, clog, or a lady’s purse; in shades of yellow, orange, and red When To Sow May to July Some Calceolaria species and their cultivars produce flowers that are not only cute but have an exotic feel. Appearing in rich, warm hues, these ovoid flowers look rather like handbags or Dutch clogs, so it’s for good reason that this plant also goes by names like lady’s purse and slipperwort. Unfortunately, there’s a drawback with growing this plant, as it hails from South America, so is not exactly easy to grow in the British Isles.1 Also, when planted in open ground as a bedding plant, it will effectively be an annual in the UK and Europe because it is so tender. Common Types While the species plant, Calceolaria integrifolia, has received the RHS’s Award of Garden Merit, the ‘Sunset Mixed’ cultivar features delightful colours and has a very long flowering season. Calceolaria integrifolia The species plant, if grown as a perennial, will eventually approach 1m in height. For 2-3 months over spring and summer, it produces flowers in a bright, sunny yellow tone. ‘Sunset Mixed’ grows to only 20cm tall, but it produces flowers in glorious yellows, oranges and reds, some with markings, streaks and splashes across its petals. With some luck, it will bloom from sometime in April to July. How To Grow Calceolaria Soil Requirements Slipper flower requires light, friable, moderately fertile soil that drains very well and is somewhat acidic. A sandy loam mixed with grit, perlite or both will make a very good base. Minimise chalk and clay as components. The best soil pH for this plant is acidic. Placement Although this evergreen sub-shrub is often grown as bedding and for borders, doing so in temperate regions such as the UK effectively turns it into an annual. I suggest that you grow this unusual sub-shrub in a container so that you can try to enjoy its special charms year after year. After the weather has warmed up in late spring, take the pot outdoors and position it somewhere it only gets dappled or filtered sunlight. A sheltered spot with an east or west-facing aspect is best. This plant thrives in a fairly narrow temperature range of 15-19°C and also prefers humid environments. In mid-autumn, you can shift it indoors. Sowing If you attempt to grow a lady’s purse from seed, I recommend that you obtain seed packets from a trusted nursery or seed company. Seeds collected by hobbyist gardeners, even from a species plant, may not be viable and can be difficult to germinate. Sow seeds between April and July. Temperatures between 17-20°C will greatly aid in germination. In small pots, sow seeds onto the surface of a seed-starting or potting mix with added sand. Moisten the medium. If sowing in April or May, put the pots in a cold frame outdoors and if sowing in June or July, cover the pot with a clear polythene sheet that has a few punctures. In either case, choose a position which gets ample dappled or filtered sunlight. Planting If you transplant Calceolarias into open ground, do so a couple of weeks after the last frost only if the weather and the soil have warmed up. You should be able to plant out in most UK locations from late May. Choose a sheltered spot that gets dappled or filtered sunlight, preferably with an east or west-facing aspect. Calceolaria Plant Care Watering & Fertilising Watering Calceolaria is a bit of a balancing act. Underwatering will be signalled by drooping foliage, but overwatering will not be signalled in good time and it may cause root or crown rot. So, while the plants require ample water, you cannot run the risk of overwatering, especially in summer. To strike the correct balance, water generously, then allow all of the soil to fully dry out before watering again. For outdoor plants during a hot, dry summer, water daily, whilst during temperate, humid weather, let the foliage be your guide! From early May until the end of the blooming season you can feed fortnightly with a very diluted solution of high-potash fertiliser. For slipper flowers, dilute the fertiliser to only 25% of the strength and also apply by half of the recommended volume. Deadheading Deadheading will stimulate fresh blooms and prolong flowering, so you may pinch off single spent blooms. However, when most of the flowers in a cluster are withered, snip off the cluster itself with a pair of sterilised secateurs. Collecting Seeds If you want to collect seeds, you will need to let the flowers stay on the shrub so that they form seed pods. After the seed pods are fully formed, you can remove them in late autumn. They can be opened with thumbs and fingers to expose the seeds. Be aware that only the seeds from the species plant will give you a chance to germinate new plants from seed. Collecting seeds from plants that are crosses or cultivars will likely be an exercise in futility. Propagation Propagating slipper flowers is a tough ask, especially in the UK. To propagate by cuttings, the best time period is July to August, during which you should take softwood cuttings. Cut just beneath a node. Insert the cutting into a well-draining mix of sand and potting compost in small pots and moisten daily. Keep the pots indoors near a window where they get the maximum amount of indirect light but no direct sunlight. Common Problems The most serious problems that may affect Calceolarias are root rot, crown rot and grey mould. The first two problems are caused by human error and are preventable by balancing the watering as described above. The third is a fungal disease that typically strikes when a plant is indoors or in a greenhouse in humid conditions. Though it is easy to spot in its early stages, no chemical controls are available to hobbyist gardeners. Grey mould can often be prevented by ensuring adequate ventilation and not overcrowding plants. Other than that, these plants may be attacked by aphids, slugs and snails. References 1. Calceolaria. (n.d.). Plants of the World Online. Retrieved August 3, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:331444-2
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