Growing
10 Wonderful White Flowering Trees For Blockbuster Garden Displays
IN THIS GUIDE 1) Robinia pseudoacacia 2) Aesculus californica 3) Crataegus monogyna 4) Catalpa bignonioides 5) Syringa reticulata 6) Cornus kousa 7) Malus sylvestris 8) Lagerstroemia ‘Natchez’ 9) Cercis canadensis f. alba ‘Royal White’ 10) Prunus × yedoensis ‘Somei-Yoshino’ References Trees with white flowers are an unmistakable focal point of any garden. Depending on the type of tree and its surroundings, it can evoke emotions of elegance, drama or romance. It’s no surprise then, that by planting one of the following trees from the list of recommendations I’ve compiled, you can bring some blockbuster beauty into your garden. When selecting a tree, be mindful of its dimensions when mature, its environmental requirements and how it will integrate with your existing display. If you get these criteria right, you are bound to have a magnificent head-turner in your space. 1) Robinia pseudoacacia COMMON NAME(S): black locust / false acacia HARDINESS RATING: H6 FLOWERING SEASON(S): spring / summer EXPECTED SIZE: 20-30m in height, 10-20m spread Despite the unpleasant connotations of its name, the Black Locust tree is a beauty to behold. A native of North America, it has been naturalised in the UK for almost 4 centuries and copes well with our temperate climate, bringing stately grace through its clusters of white flowers in May and June, which are a magnet to bees.1 Later, in autumn, its seed pods will also draw in hummingbirds. It can grow to anywhere between 10-30m tall, though vigorous pruning will keep it in check if need be. However, it does boast a prodigious growth rate, leading some to classify it as a weed outside of its home environment. You should also be aware that its branches can bear sharp bracts that are capable of tearing clothes. “This tree has a tendency to die back and drop branches, so it is best to not plant it near a path or seating area,” shares Horticultural Consultant Dan Ori. 2) Aesculus californica COMMON NAME(S): california buckeye HARDINESS RATING: H6 FLOWERING SEASON(S): spring / summer EXPECTED SIZE: 8-12m in height, 10-18m spread This medium-sized tree shouldn’t exceed more than 12m in height and can resemble a shrub due to its growth habits. As such, it’s the perfect choice for slightly smaller spots which are simply in need of filling out. The flowers, which burst forth every spring and last all the way through summer, are robust conical creations that are largely white in colour, but with yellow throats that turn pink later in the season. California Buckeye trees also bear conkers and fruit. 3) Crataegus monogyna COMMON NAME(S): common hawthorn / hedgerow thorn HARDINESS RATING: H7 FLOWERING SEASON(S): spring EXPECTED SIZE: 4-8m in height, 4-8m spread Hawthorns are another medium-sized specimen, with the common hawthorn reaching a slightly smaller height than the Californian Buckeye. Their flowers are daintier in their dimensions, with a profusion of small white blossoms appearing in spring and giving way to red berries in the summertime. These splashes of colour, alongside the fact that the foliage on a Hawthorn tree often begins life as a reddish-brown before maturing to green, make it ideal for adding extra tones to your garden’s palette. Like the Black Locust, it can also have spiny branches, so take care when handling it or passing nearby, and be on the lookout for signs of powdery mildew since Hawthorns are highly susceptible to this disease. 4) Catalpa bignonioides COMMON NAME(S): indian bean tree / catawba HARDINESS RATING: H6 FLOWERING SEASON(S): summer EXPECTED SIZE: 10-18m in height, 6-12m spread The Indian Bean Tree goes by many names, including the common Catalpa and the Southern Cigar tree. Whatever you call it, it’s an impressive specimen which can grow nearly as wide as its height – up to almost 20m at full maturity in optimum conditions. The tree is remarkable for its heart-shaped foliage and its trumpet-like blooms, which won’t blossom for the first six or seven years after planting, but should appear regularly thereafter. They’re mostly white but do have yellow and pink ornamental colourings at their epicentre. As they like to spread their limbs and because the petals and seedpods are prone to falling to the ground, it is advisable to plant them away from buildings and walkways. 5) Syringa reticulata COMMON NAME(S): japanese tree lilac HARDINESS RATING: H7 FLOWERING SEASON(S): summer EXPECTED SIZE: 6-8m in height, 4-6m spread One tree which is good for lining pathways is the Japanese Tree Lilac. In my experience, this tree never exceeds 10m in height, but it’s an obedient creature and can be easily kept in line if you wish to restrict its growth further. It also provides good density, making it an ideal screening option. The panicles of soft, feathery flowers appear in May and ooze an exquisite aroma, which is another string to its bow. These blossoms are complemented by the dark green foliage behind them which, along with its attractive bark and olive tree-like dimensions, makes it a highly sought-after specimen. 6) Cornus kousa COMMON NAME(S): kousa / Szechuan strawberry HARDINESS RATING: H6 FLOWERING SEASON(S): summer EXPECTED SIZE: 4-8m in height, 4-8m spread Kousa Dogwood is another tree of relatively modest dimensions, rarely surpassing 10m in height. It also has eye-catching architecture, with its slender trunk suddenly giving way to a profusion of tangled branches, making it resemble a bouquet of flowers or a collection of balloons. Its aesthetic qualities are at their most powerful in the summer months when the delicate flowerheads, composed of interestingly shaped white petals, cover its foliage at will. It is disease resistant and hardy in most climates but, like others on this list, can be susceptible to powdery mildew. 7) Malus sylvestris COMMON NAME(S): crab apple / wild crab HARDINESS RATING: H6 FLOWERING SEASON(S): spring EXPECTED SIZE: 8-12m in height, 4-8m spread Crab apples are a diverse species, with cultivars available in a range of sizes and shades. That means those gardeners in search of one which produces white flowers should have no trouble in satisfying their requirements, regardless of the space available to them. For the best results, select one which doesn’t succumb to disease easily. Whichever specific Crab apple you opt for, you’ll be richly rewarded with a sturdy tree that offers an intriguing triangular shape and a strong blooming habit. As an added bonus, it also produces fruit which lasts through the year up to winter and will be a welcome source of sustenance for birds once the weather turns. 8) Lagerstroemia ‘Natchez’ COMMON NAME(S): Natchez crape HARDINESS RATING: H3 FLOWERING SEASON(S): summer / autumn EXPECTED SIZE: 4-8m in height, 4-8m spread This Lagerstroemia was specifically engineered to be more resistant to powdery mildew in the US, with its name a nod to the indigenous tribes in the area of its provenance.2 It will handle UK temperatures just fine, but be aware that it may not flower strongly in weaker summers. Having said that, even a barren blooming season is not a cause for despair with a Natchez Crape. That’s because it’s lauded for its fine architectural shape, textured bark and, best of all, the stunning collage of colours it runs through in the autumn months. If the flowers blossom, so be it, but they’re not the be-all and end-all for this smaller option. 9) Cercis canadensis f. alba ‘Royal White’ COMMON NAME(S): white-flowered eastern redbud ‘royal white’ HARDINESS RATING: H5 FLOWERING SEASON(S): spring EXPECTED SIZE: 4-8m in height, 4-8m spread Another option on the smaller side, the ‘Royal White’ Redbud doesn’t usually grow past 8m, though it might reach that height in a surprisingly short time due to its vigorous growth habit. Its pleasing architectural shape is reminiscent of a vase, which is apt because of the gorgeousness of the flowers it bears. Interestingly, ‘Royal White’ Redbuds don’t bear flowers and foliage at the same time. This means that when in bloom, its delicate white blossoms will completely cover its spindly branches, giving it a truly unique appearance. Later, when these have faded, they’ll be replaced by heart-shaped leaves that are just as easy on the eyes. 10) Prunus × yedoensis ‘Somei-Yoshino’ COMMON NAME(S): Yoshino cherry / Japanese flowering cherry HARDINESS RATING: H6 FLOWERING SEASON(S): spring EXPECTED SIZE: 5-10m in height, 5-10m spread Yoshino is a species of Japanese Cherry Blossom which is everything you could want and more in a tree of this kind. It’s a knockout addition to any garden, with its foliage starting life with red hues that soften to green, whilst its flowers appear before many of its counterparts in March or April. The subtle almond fragrance they exude completes the package. Yoshino Cherry Trees normally grow to about 10m in height and spread and they aren’t fussy about the type of soil you give them or the diseases which try to bring them down. They do, however, demand at least 6-8 hours of sunlight a day, so make sure your specimen is planted in an appropriate location. References 1. Robinia pseudoacacia. (n.d.). Kew Royal Botanic Gardens. Retrieved March 27, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:30034699-2 2. Gilman, E., & Watson, D. (1993, November). Lagerstroemia x ‘Natchez.’ US Forest Service. Retrieved March 27, 2023, from https://hort.ifas.ufl.edu/database/documents/pdf/tree_fact_sheets/lagxe.pdf
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How To Grow Potted Willow (And Why Many Salix Are Not Suited To Containers)
IN THIS GUIDE Can You Grow Salix In Pots? Choosing Willow Varieties For Pots Choosing Containers For Salix Potted Willow Compost Requirements Potting Up Salix Potted Willow Care References Salix species, which we commonly call willows, sallows or osiers, are a diverse range of beautiful trees and shrubs with varied sizes and forms. Many can be coppiced or pollarded in order to provide a yield of willow ‘whips’ for a range of uses, whilst some can also be trained to create beautiful fences or other living willow structures. If you are drawn to the beauty or utility of the salix species but can’t grow them in the soil where you live or have limited space, you might be wondering whether you can grow any of them in pots. Difficulty Hard Equipment Required Pots or containers, suitable compost mix, water, salix Can You Grow Salix In Pots? The answer is a little more complex than a simple yes or no. Salix is a genus with around 400 different species, many of which can be grown in UK gardens.1 In general, willows are not necessarily the easiest plants to grow in containers, but that does not mean that there you cannot attempt to grow some salix varieties in this way. When looking at whether or not we can grow any plant in containers, we need to look at the size to which they will grow, the form of their root systems and their water requirements. First, let’s take a look at their size. Salixes can differ extremely in the size to which they will eventually grow. Some willows will grow into very large standard trees, while others will remain relatively compact or grow with a more shrubby, multi-stemmed form. Larger willow trees will not be good choices for container growing at all, but some smaller standard trees or extremely compact weeping forms can potentially be grown in containers. Shrub willows can also be an option for containers, especially when coppiced on a regular basis. However, even the types that remain compact in form and those that can be regularly cut back hard to keep them contained can be challenging to grow in containers. The first reason for this is that many willows tend to have extensive root systems that can extend into a large area below the soil. Constricting their roots can put a strain on these plants and may lead to issues when growing them in containers. Another reason is that willows often have high water needs. Even those that are small enough to grow in containers do need to be well watered throughout the growing season and it can be challenging to meet these water needs when they are grown in pots. This is not to say that it cannot be done with some varieties, but it is important to note that providing the correct care will be essential. Choosing Willow Varieties For Pots When choosing a salix for a container, it is important to understand the needs and characteristics of the specific type and variety that you wish to grow. As mentioned above, many willows are completely unsuited to container cultivation. Some that can be grown in containers are: Kilmarnock willow (S. caprea) Flamingo willow (S. integra ‘Hakuro Nishiki’) Swiss willow (S. helvetica) Woolly willow (S. lanata) Willow ‘Boydii’ (S. ‘Boydii’) “You will normally find that Salix varieties suitable for containers have been top-grafted, which is a cultivation technique where a long single-stem rootstock is cut at a desired height (typically around 1m) and a sion (cutting) is attached,” shares Horticultural Consultant Dan Ori. “The rootstock will control the vigour of the plant making it achievable to successfully grow a species like Salix caprea in a container.” Choosing Containers For Salix When choosing a container for a salix tree or shrub, it is important to select a pot that is as large as possible to accommodate the variety you have chosen. Make sure that it is heavy and sturdy enough to support a small tree or shrub and that it will not blow over in windy conditions. Willows typically need free-draining conditions but still require the soil to remain consistently moist through the growing season. So, make sure that the container does not lose moisture too quickly, but also that excess water can drain away freely at the base. Potted Willow Compost Requirements A mix of two parts soil-based compost (John Innes No 3 or equivalent) and one-part peat-free multipurpose compost is ideal when growing salix in containers. Remember that any mix that you choose must be reasonably free-draining but still retain sufficient moisture. The mix should also be reasonably rich in organic matter to provide fertility for your salix plant. Potting Up Salix Salixes can be purchased as bare-root specimens or as pot-grown plants. Typically, dwarf varieties are purchased in pots. As soon as these are purchased and reach your home, you should be sure to pot them up into their long-term containers by following the steps below. Firstly, make sure that you water the plant well. Prepare the new container, ensuring that it is large enough to accommodate the existing root system of the plant. Place a little of the growing medium at the base of this new container. Remove the plant from the pot it came in and position it in the new container on top of the growing medium you have placed there. Make sure that once the rest of the pot is filled, the salix will sit at the same depth as it sat at in its previous pot. Next, add more of the growing medium around the sides of the existing root system and firm this into place gently, making sure that you do not compact the medium too much, taking care to avoid the creation of air pockets. Finally, water in the salix; watering deeply whilst ensuring that excess water can drain away freely. Consider adding a moisture-retaining mulch of homemade compost, wood chip or other organic matter around the top of the container, but make sure not to mound this around the trunk at the base of the plant. Potted Willow Care Place your container in a location with full sun. Keep your salix well watered during the growing season, making sure that the medium does not dry out, but also making sure that the conditions do not become waterlogged. Pruning will depend on which variety you are growing. In general, only light maintenance pruning is required for tree types, but some shrubby types can be cut back harder on occasion to promote the growth of decorative stems. Look out for pests like aphids, caterpillars, willow leaf beetles and sawflies, and be aware of fungal diseases. Pot up your salix into a slightly larger container with a new growing medium every 2-3 years, especially when growing a standard tree type. References 1. Harris, S. (n.d.-c). Salix species. Oxford University Plants. Retrieved March 27, 2023, from https://herbaria.plants.ox.ac.uk/bol/plants400/Profiles/st/Salix
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Light Pruning Is Possible On Mature Willows; Pollarding Schemes Are More Complicated
IN THIS GUIDE Do Willow Trees Need To Be Pruned? When To Prune Salix How To Prune Willows Small Trees Mature Trees Coppicing, Pollarding Or Stooling References Plants in the Salix genus, commonly called ‘Willows’, are deciduous trees that can often grow well in our temperate climate. Willows can be great choices for many UK gardens, but it is important to understand how to care for them correctly – and pruning is one important area to consider. Difficulty Easy Equipment Required Secateurs, pruning shears, a saw When To Prune Winter or early spring Do Willow Trees Need To Be Pruned? Many mature willow trees fall into RHS Pruning Group 1 and do not require much pruning at all, as they naturally retain a well-shaped framework and form.1 There is a wide variety of different willows that grow in UK gardens in a range of forms and sizes. Willow species and cultivars can be extremely large trees or relatively small shrubs, with a range of sizes in between. So, when growing willow in its natural form, it is important to choose one suited to the size of your space. It can be challenging to keep a mature willow tree in check and you cannot really make major changes to the structure and size of a mature standard willow tree. “You may find it hard to find a professional who will want to undertake subtle pruning of large willow trees because the branches can snap easily,” shares Master Horticulturist Dan Ori. “If you undertake pruning never climb a tree or rest a ladder against its branches. My best advice for a large tree is to pick the right species for the spot, prune out poor growth when the tree is young, and for anything else, get a tree surgeon in. “Remember to be realistic about what can be pruned due to the snapping tendency of its branches.” A little light pruning is possible on mature trees, but it is generally best to keep this to a minimum, whilst some pruning may be undertaken to shape a young willow while it is still small. However, things get a little more complicated when we look at willows that are grown for coppice or pollarding schemes. A number of willows are not grown as standard trees with a single trunk but are instead cut back more severely, in order to encourage the formation of thin whips that can be used in a wide range of ways. When willows are grown in a pollarding type system, they are cut back hard on a regular basis every 3-4 years depending on the species chosen, the yields desired and what they are to be used for. “Coppicing is not common and it is not suitable for some willow types,” says Dan. “Coppicing is taking the tree down to a stump allowing new stems to grow from it. Some people will mistakenly refer to pollarding as coppicing due to the similar approach of cutting back hard.” Another thing to consider is that certain varieties of willow can also be trained to form structures or barriers, which will require more pruning. When To Prune Salix Willows can bleed sap when pruned during the growing season. Therefore, it is best to prune in the late winter or in early spring, either while they are still dormant or just as new growth emerges. Initial shaping and maintenance pruning on standard willow trees is generally carried out during the dormant phase and many species are also coppiced during this time. However, varieties of willow grown for colourful stems are typically pruned in early spring, just as new growth begins to emerge. The only time when a little pruning may be carried out on salix species in summer is when they are being grown as a living hedge or have been trained into another structure. In such cases, some summer pruning may be required in addition to winter pruning to keep the shape of the structures. How To Prune Willows While many willow trees won’t need much pruning at all, it is important to consider the specific salix you are growing and to make sure that you adopt the right approach for the variety, stage of growth and what you are aiming to achieve. Small Trees When shaping a young willow tree to become a standard tree, you will typically select a central leader showing strong upright growth and make sure that you prune out any competing stems. Any damaged branches should be removed, along with those that grow upwards instead of outwards or those which are overcrowded. The aim is to create a clear, evenly-spaced structure of well-placed branches. Mature Trees Mature willow trees can and should largely be left to their own devices where possible. However, it is a good idea to check over the tree in winter and to undertake simple light maintenance pruning by removing any branches that are dead, damaged or diseased and those that are rubbing against one another. Where, for aesthetic reasons, you wish to shorten branches, you can do so sparingly, as long as you always cut just above a twig or leaf bud. Weeping willow forms are particularly popular in many gardens. Weeping branches can sometimes reach right down to the ground, so you may wish to shorten these for practical or aesthetic ones. You can shorten these as required by, again, cutting just above a leaf bud. Coppicing, Pollarding Or Stooling A number of salix species are ideal for use within a coppicing or pollarding scheme and can often respond well to being cut back hard. Coppicing and pollarding are techniques often used when pruning willows to encourage the formation of new growth on multiple stems. We may wish to undertake this form of pruning in order to obtain thin willow branches, also known as whips, for use in basketry or other crafts. Some shrub willows, grown for winter stem colour, are also coppiced in order to encourage the formation of new, more colourful stems for ornamental appeal in a garden. Coppicing involves cutting back close to the ground, whilst pollarding involves cutting off branches to create whippy growth at a certain height above the ground. When coppicing, all the stems of the tree are simply cut back to within 5-7.5cm of the ground. However, pollarding allows you to cut the stubs of the previous year at your desired height. When willow trees are coppiced or stooled regularly, they should quickly spring into new growth. References 1. Shrubs and trees: light pruning. (n.d.-d). Royal Horticultural Society. Retrieved March 27, 2023, from https://www.rhs.org.uk/plants/types/trees/trees-shrubs-light-pruning
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Expert Gardeners Teach How To Grow Arbutus Unedo AKA ‘Strawberry Tree’
IN THIS GUIDE Overview Common Varieties How To Grow Strawberry Tree Strawberry Tree Care References If you are looking for a small evergreen tree for your garden which can also provide an edible yield, then the strawberry tree, Arbutus unedo, could be a good choice. This tree is not native, though it is native to Southwest Ireland, but it can survive and even thrive in many UK gardens. “Arbutus unedo is one of my favourite trees and I had two of them in my garden at the Chelsea Flower Show in 2017,” shares award-winning Garden Designer Manoj Maldé. Overview Botanical Name Arbutus unedo Common Name(s) Strawberry Tree Plant Type Tree / Shrub Native Area Southern Europe, Ireland and Asia Hardiness Rating H5 Foliage Evergreen Flowers White or pink bell-shaped blooms When To Plant September to November Harvesting Months November to December When To Prune February to March Arbutus unedo is a large bushy shrub that is often pruned to give it a more tree-like form. Although it is commonly referred to as the ‘Strawberry Tree’, this plant is not related to the common garden fruit you might be more familiar with. This evergreen tree is a great choice for gardens, relatively compact in size and provides plenty of visual appeal throughout the year. It is especially attractive between September and November, which is when the flowers and fruits are both born at the same time. This tree is tolerant of a wide range of growing conditions and can be very resilient once established. Opinions differ about how tasty the fruits may be, but they are edible.1 “Perhaps the common name of Strawberry Tree sets the bar too high, but from experience, the fruits are not very tasty,” shares Colin Skelly, a Horticultural Consultant with experience that includes 5 years at The Eden Project. “They do look good on the tree though. Arbutus unedo is also a wind-tolerant tree for coastal locations.” They can be eaten raw and are often used to make preserves like jams and jellies, either on their own or in combination with other ingredients. Common Varieties In the UK, the Royal Horticultural Society has given two cultivars an Award of Garden Merit. The first with an AGM is A. unedo f. rubra, which is a variant with pink flowers. The second is the cultivar A. unedo ‘Atlantic’, with white flowers. “I would, love an A. x andrachnoides in my current garden, but they are so hard to find,” says Manoj. How To Grow Strawberry Tree A. unedo works well as a stand-alone specimen tree, as part of a forest garden design or in a mixed border. It is frequently used to stabilise and improve soils and is a pioneer plant often used in certain parts of the world in ecosystem restoration and to redress deforestation.2 It also can be used as an ornamental in gardens. It might be a good plant for where soils are poor and other fruiting trees or shrubs are failing to thrive. This tree will do best in areas where the soil is free-draining, as it cannot cope with waterlogged soil. Even though it is in the Ericaceae plant family, most of which are acid-loving plants, it is unfussy about pH and can even cope with alkaline conditions. Planting Arbutus unedo trees are best purchased and planted in the autumn. You should think carefully about where you initially plant them, as these trees do not always take well to transplantation. Younger trees are best purchased because these will usually establish most easily. Dig a hole large enough to accommodate the root system and then place the tree inside. Fill back the soil around the tree, water in well and then mulch with organic matter. Growing From Seed Though A. unedo can be grown from seed, this can be challenging and is a time-consuming process, so most gardeners will choose to purchase this plant instead. Seeds need to go through a month-long period of cold stratification and are then soaked in warm water for 5-6 days to improve germination rates. Even after this, germination success rates rarely exceed around 20%. Seedings are very fussy and are prone to damping off and fungal issues. They will need to be mollycoddled for their first year. Strawberry Tree Care Light & Aspect This tree needs full sun to fruit well and should be placed in a sheltered position here in the UK. A south or west-facing aspect is ideal. In small spaces, this tree might be espaliered against a south-facing wall. Overwintering A. unedo will survive temperatures down to -15°C and has a hardiness rating of H5. Watering & Feeding Water regularly during dry spells until the tree becomes established. Once mature, the tree should have reasonable drought tolerance. Replenish the mulch around the tree each spring to provide fertility, retain moisture and suppress weeds. It is also a good idea to consider creating a guild with beneficial companion plants around this fruit tree (see below). Pruning Pruning is not usually required and any pruning should be light. Simply remove dead, damaged, diseased or poorly-placed branches in the late winter or early spring. Common Pests & Diseases The tree is susceptible to aphids, though this can be easily handled by attracting wildlife that eats them to your garden through companion planting. Aim for as much biodiversity in your garden as possible. Though usually not plagued by many issues, Arbutus leaf spot is one problem that may occur. Propagating Though seed propagation is challenging, it is, of course, possible. An easier way to propagate these trees is through semi-ripe cuttings taken during the summer months. Companion Planting You should consider making a guild of beneficial companion plants, which might include: Spring-flowering bulbs Yarrow Comfrey Clovers Mediterranean herbs References 1. Gardens, K. (n.d.). “Strawberry Tree.” Kew Royal Botanic Gardens. Retrieved March 9, 2023, from https://adoptaseed.kew.org/seed/strawberry-tree.html 2. Strategies for the improvement of Arbutus unedo L. (strawberry tree): in vitro propagation, mycorrhization and diversity analysis. (2011). Universidade De Coimbra. Retrieved March 9, 2023, from https://core.ac.uk/download/pdf/19131968.pdf
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Brown Leaves On Your Apple Tree? These Solutions Can Help With Recovery
IN THIS GUIDE 1) Waterlogging & Root Rot 2) Underwatering 3) Apple Scab 4) Fireblight 5) Chemical Burns 6) Potassium Deficiencies References If you have a prized apple tree in your front yard that is a joy to behold in spring when it colours up with fragrant apple blossoms, brown leaves might become an annoyance. The bounty of luscious, juicy apples that you harvest season after season might be up against leaves that are browning quite alarmingly, and you might be wondering what to do. Well, firstly, you need to try to figure out the problem or diagnose the disease, as apple tree foliage can brown from a multiplicity of causes, including: Waterlogging that causes your apple tree’s roots to rot. Underwatering your apple tree. Apple scab. Fireblight on your apple tree. Chemical burns caused by the overapplication of chemical spray on your apple tree. Potassium deficiencies in your apple tree. I outline the factors that will allow you to identify the cause and treat it below. 1) Waterlogging & Root Rot Though an established tree in open ground is rarely affected by overwatering and waterlogging, a sapling or a young tree may succumb to root rot, especially if it is planted in heavy, dense soil coupled with prolonged rains or excessive watering. The only way to save the affected tree is by digging it up, cutting off the rotten portions of the roots and transplanting it into more amenable free-draining soil. The common signs that waterlogging is the issue includes: The leaves curling up. The browning starting at the tips and the edges of the leaves. 2) Underwatering If your apple tree has the following symptoms, then it might not be receiving enough water: The leaves are covered in random greeny-brown spots. These patches are randomly positioned over the leaves. They occur on both sides of the leaf’s surface. The branches from the tree are cracked and blistered. This problem is the easiest one to rectify on this list, though you should make sure that the diagnosis is correct by checking your watering schedule. You could also examine the soil down to several centimetres for moisture. Give the tree a thorough soaking and then re-commence regular watering. Water in the morning with cool water for the best results. 3) Apple Scab Apple scab is a fungal disease that only some cultivars are susceptible to, but these include 3 of the most popular – ‘McIntosh’, ‘Red Delicious’ and ‘Cortland’.1 Best practice indicates avoidance measures such as the prompt clearance of shredded leaves and the pruning of diseased branches. Alhough fungicides to control this disease are available, they are prohibited for use on fruiting trees. You may treat a diseased apple tree with a fungicide, as long as you first ensure that it will not injure the tree and that you discard and destroy that season’s entire crop of apples. You can identify apple scab from these symptoms: The leaves on a given shoot or branch are almost all browned. The leaves look like they’ve been scorched. The flowers on the tree have wilted and withered. Younger shoots have developed a hook or crook. There is some oozing or canker on the bark of the tree. 4) Fireblight This bacterial disease is a serious one as, unfortunately, it has no cure. To diagnose fireblight, check for the following: The brown leaves are scattered throughout the tree. The browning does not follow any pattern. You have used chemicals on your tree recently. The weather has been particularly sunny and hot and your tree has been exposed to it. If the problem is caught early enough, your best shot is to trim and prune all of the diseased parts of the tree, including the branches. This is a somewhat complicated operation which you will need to research thoroughly before attempting or bring in a tree doctor to do the job for you. Sadly, in extreme or advanced cases, the diseased tree must be entirely destroyed. 5) Chemical Burns “The foliage of your apple tree might have been burnt by chemical sprays, such as pesticides,” shares Colin Skelly, a Horticulturist whose previous experience includes 3 years working as a Gardener at St.Michaels Mount. Other symptoms apart from brown leaves include: Yellowing and/or browning of the leaves. Distorted growth. Small, mishapen or curled leaves. Luckily, if the affliction is not excessive, the tree will heal. “Avoid further spraying of any chemicals and maintain moisture levels,” shares Colin. “If the spray was a contact chemical then pruning out the affected area may limit the damage. “If it was systemic (e.g., glyphosate), this will be less effective. “The tree may recover over time but roots will be impacted, as well as foliage and stems.”2 6) Potassium Deficiencies Apple trees require a soil pH in the moderately acidic range for the efficient uptake of nutrients from the soil. If they are not receiving enough potassium, the leaves of the tree might begin to turn brown. The main symptom includes brown edges on the leaves that may spread towards the centre of the leaf.3 Alkaline soil can arrest the uptake of potassium from the soil. References 1. Bill Shane, Michigan State University Extension. (2014, February 20). A review of apple scab-resistant varieties for commercial growers. MSU Extension. Retrieved March 9, 2023, from https://www.canr.msu.edu/news/a_review_of_apple_scab_resistant_varieties_for_commercial_growers 2. Weedkiller damage / RHS Gardening. (n.d.). Royal Horticultural Society. Retrieved April 11, 2023, from https://www.rhs.org.uk/prevention-protection/weedkiller-damage 3. Potassium deficiency | Apples. (2018, April 30). Yara United Kingdom. Retrieved April 11, 2023, from https://www.yara.co.uk/crop-nutrition/apples/nutrient-deficiencies-apples/potassium-deficiency-apples/?activeSlide=4213
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Apple Trees Are Usually Amenable To Transplanting - But Follow These Steps
IN THIS GUIDE Considerations Before Transplanting 1) Prepare The Tree 2) Prepare The New Site 3) Remove The Tree 4) Transplant And Backfill The Hole 5) Water And Apply Fertiliser Apple trees are one of the fruit trees that are most amenable to transplanting. That should not be taken to mean that transplanting an apple tree is easy – it’s far from it. You can transplant an apple tree by following these steps: Start preparing the apple tree for transplanting. Prepare the new planting site for your apple tree. Remove the apple tree from its current position. Transplant the tree and backfill the prepared hole. Nurse the stressed apple tree. This process is explained in more depth below. Difficulty Hard Equipment Required Gardening gloves, shovel, hoe, pruning shears, burlap or sackcloth When To Transplant February or March Considerations Before Transplanting If this job is done carelessly or incorrectly, transplant shock can kill an apple tree. To cut to the chase, the critical factors to be mindful of are: The age of the apple tree. The preservation of the root system. The new soil line not being any lower than the original one. The differences between the old and new environments. For a young apple tree up to 3 years old, the chances of a successful transplant are very high. For a tree aged between 4-6 years old, the chances are good. For a tree more than 6 years old, the chances are poor, so a tree in this age group ought not to be shifted. The degree of transplant shock (which will be suffered to some extent) can significantly be reduced if the old and new environment and soil are very similar. Transplant shock will, of course, also be reduced if the tree is prepped properly. 1) Prepare The Tree If you know your plans a year in advance, prep a 4-6-year-old tree by stimulating the growth by feeding the roots and doing a light prune during the winter dormancy. In January or February, make a trench around the tree’s drip line that is about 25cm wide and deep. Fill it in with sand, preferably mica sand. This will stimulate the growth of feeding roots. Prune the tree lightly, only removing old or congested limbs and protruding branches that could be damaged in transit. Do not prune more than a quarter of the growth. 2) Prepare The New Site In February or March, a few days before you intend to transplant the tree, prepare the transplanting site. Select a spot in the new location where the exposure and aspect are as close as possible to that of the tree’s present spot. This should preferably be in a shaded position with some sun, as Julie Bellemann from Sheffield Fruit Trees explains: “Taking your time to plant it correctly, in a place with sufficient levels of sun, is very important.” Examine the soil that the tree is growing in and try to match, as far as possible, the soil of the transplanting site to that of the current spot. Also, prepare that same type of soil for backfilling the transplanting hole. At the very least, the new site’s soil should not be too divergent from the current spot’s soil. Thoroughly clear the site of all weeds, then dig a hole that is about 25% wider than the tree’s drip line and about 30cm deep. Mix in a little of the new soil into the hole. The day before the tree is to be dug up, water it well. 3) Remove The Tree On a sunny morning in February or March, remove and transplant the tree, making sure you have time to complete this task in one day. If necessary, mark the soil line at the base of the trunk, which can almost always be distinguished by a difference in colour. It is critical to know where the soil line was at the time of transplanting. Secure the branches by wrapping a few coils of natural-fibre rope around them, tying them loosely. To dig up the tree, you should first probe the extent of its root system by digging around the canopy. Adjust the width of the circle depending on whether or not you encounter roots as you dig deeper. Although a little damage to the roots will be unavoidable, it is imperative to limit this to the bare minimum. When the lower roots are freed, prise up the tree when it is tilted over while supporting it, taking care to keep as much of the root system intact as possible. Wrap the roots loosely in a damp burlap or sackcloth and place the tree on similar material prior to transporting it to the new site. 4) Transplant And Backfill The Hole Now that the tree’s root system can be observed, adjust the transplanting hole so that it is of the right depth and twice as wide as the root system. Water the hole, including its sides and the surrounding ground. Remove the wrapping material for the tree, spread out the roots and place it in the hole, making sure to spread out the roots once more. Examine the set of the tree and adjust vertically as necessary so that the soil line and the surface of the ground will be level when the hole is backfilled. Start to backfill the hole. As the hole is backfilled, keep watering in moderation to keep the soil moist. Also, keep patting down and firming up the soil and try to ensure that there are no air pockets. Backfill the hole up to the soil line at the base of the trunk. You may backfill to a touch below the soil line but not higher than it. “Keep an eye on the soil line for a few months,” says Master Horticulturist Colin Skelly. “It is likely to drop as the compost settles in the planting hole. “Top up the soil level using the same principles to avoid the tree sitting proud and exposing the top layer of roots.” Firm up the soil well and give the tree a thorough watering. 5) Water And Apply Fertiliser Apply an organic mulch (such as bark, leaves, hay or straw) around the tree at a distance of several centimetres from the base of the trunk. Water the tree periodically. “Make sure to give it sufficient water, particularly if it is a potted plant as they’ll require more care than a free-standing tree in the ground,” says Julie. Though it certainly should not be watered as it would be in the growing season, it should be watered more than normal during dormancy, as water will assist in recovery from transplant shock. Give the tree a month or so to settle down. Then, instead of your customary feeding, fertilise it with a high-phosphorous formula. Apply a high-phosphorous fertiliser at 60-70% of the quantity and strength directed by the manufacturer for a fruit tree of that particular size and age. Alternatively, work in a couple of pinches of bonemeal into the soil in a ring below the tree’s drip line. Water in the fertiliser and then leave your transplanted tree to grow.
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Tackling Aphids On An Acer Tree - Why Organic Solutions Are Always The Best
IN THIS GUIDE Are Aphids A Problem For Acers? Pest Management In An Organic Garden How To Deal With Aphid Infestations Acers, when grown in the right spots, are typically trouble-free trees to grow. However, on occasion, small pest problems can arise. One pest species that you may spot on your Acers is aphids. Are Aphids A Problem For Acers? Aphids are small sap-sucking insects that usually will not be a major issue for Acers. Even if you do see some aphids on your Acer, they will not usually become a big problem, nor dramatically affect the growth or health of the plant. However, they are attracted to these trees and, if you have a major infestation, this can lead to poor or distorted growth. Growing on the honeydew that aphids excrete, you may also begin to see sooty moulds developing. Pest Management In An Organic Garden One thing that it is important to remember in any organic garden is that we need some pests. Aphids, like many other pest species, are important elements in the food chain and are eaten by a range of different wildlife in your space. Without aphids, other beneficial wildlife would suffer and biodiversity in your garden will be lower, which can cause a range of knock-on problems. If you try to eradicate aphids entirely by using pesticides, you can end up with an environment depleted of their natural predators, which is when the aphid population can get out of control. How To Deal With Aphid Infestations To tackle aphids that are present on your Acers, one of the best things to do is to think about how you can make sure your garden is as rich in wildlife as possible. Planting companion plants which attract aphid predators like ladybirds, lacewings and hoverflies around an Acer is the most important step to make sure aphids don’t get out of control. Coriander, yarrow, cosmos and nasturtium are all said to help attract ladybirds naturally. Less Is More If you can, it is best to tolerate aphids on trees like Acers. If your garden has a healthy ecosystem, by late summer, predators should have restored natural balance and kept their numbers in check. Less is often more when it comes to controlling aphids in an organic garden. However, if there are excessive numbers of aphids before natural predation comes into play, you can simply squash these by hand or use a hose to knock them off the Acer that they are damaging. “Aphids are usually a minor problem with Acers,” says Agustin Coello-Vera, the Chairman of The Maple Society. “If needed, you can often control aphids by wiping or spraying the leaves of the plant with a mild solution of water and a few drops of dish soap.” This is a technique mirrored by RHS Master Horticulturist Dan Ori: “Spraying the aphids directly with a solution of non-biological dish soap should block the breathing pores on the backs of the aphids. “The concentration I use is a sixth of a teaspoon of standard concentration non-biological washing-up liquid to 500ml of water; I apply this early in the morning or evening and I would normally rinse off with water after a few hours if the plant is not in direct sunlight, you may need to repeat this over multiple days to bring aphid levels down to a tolerable level.” See this video for a demonstration of the process from Dan himself: Just remember, you should then take steps to prevent a reoccurrence by attracting beneficial predatory insects and other wildlife to your garden.
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Agustin Coello-Vera On The Four Causes Of Acer Leaf Browning
IN THIS GUIDE What Is Leaf Scorch? 1) Frost Damage 2) Drying Winds 3) Sun Damage 4) Water Problems Yellowing Leaves Acers can often be relatively easy plants to grow and make great trees for many gardens. However, if you would like to grow an Acer tree where you live, the most important thing is choosing the right location in which to do so. You must select the growing position carefully and provide the right environmental conditions or your Acer will fail to thrive. One of the most common issues seen by those growing Acers is brown leaves, which is often known as leaf scorch. “Brown leaves are a sign that the tree is not happy,” explains Agustin from The Maple Society. “This could be caused by many different environmental conditions, including too little or too much water and too much sun. “Some pests and diseases will also result in leaf browning.” Maple leaves turning brown is typically an issue which arises due to environmental stresses. In short, it can be caused by: Frost and cold conditions impacting your Acer. Drying winds and growing your Acer tree in a position that is too exposed. Intense sunlight getting to your Acer leaves. Issues with watering your Acer tree. Read on for more detail about each of these reasons and for some advice on prevention. What Is Leaf Scorch? When Acer leaves turn brown on the tips, curl up or begin to shrivel, we call this leaf scorch. Leaf scorch happens whenever, for one reason or another, the leaves are losing moisture more quickly than water can be taken up through the roots. Acer leaves may naturally turn brown as part of their natural abscission process, when they lose their leaves in autumn. However, what we are talking about here is when leaves turn brown during a part of the year when they would not naturally do so. The 4 main reasons for this include: 1) Frost Damage If there is a late cold snap in the spring, new Acer growth may be damaged by the cold conditions. Though these are generally hardy trees, the new growth will be more tender. As long as the maple is not in too exposed a location, it should recover once the weather warms. 2) Drying Winds Even if there is no frost, a maple in an exposed location may also become damaged by winds, which dry the foliage out quickly and make it difficult for the plant to obtain the moisture it needs. Moving the Acer to a less exposed location or planting wind-breakers could help prevent the problem from happening again. 3) Sun Damage If Acer leaves turn brown in summer, this could be due to intense sun and heat which increase the speed of moisture loss from the foliage. Placing an Acer where it gets some light shade during mid-summer at the hottest part of the day could help prevent browning for this reason. 4) Water Problems Maple leaves may also turn brown due to issues with waterlogged soil or environmental conditions which do not allow excess water to drain away, as this can lead to root rot. Make sure that you water regularly to keep the conditions moist throughout the summer, but ensure excess water can drain away freely. Yellowing Leaves What if your leaves are turning yellow or are off colour and it is not autumn? According to qualified Horticulturist Dan Ori, “this could be due to disease, pest attack, exposure to cold, conditions too dry, conditions too wet, too much sun, or it could also be something called Chlorosis which is a nutrient deficiency common in Japanese maples grown in high pH (alkaline) conditions.” “To mitigate Chlorosis in Acers caused by high pH, repot or top-dress with ericaceous compost and water with rainwater if possible.”
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From Overwatering To A Lack Of Light: The Typical Reasons For Yellowing Leaves On Yucca
IN THIS GUIDE 1) Overwatering 2) A Lack Of Light 3) Pests 4) Old Age If there was ever a list of plants for a neglectful gardener the yucca plant would probably be at the top. This plant is incredibly low maintenance and thrives when watered very sparingly. In fact, if you notice something amiss with your yucca, it’s probably because you are actually doing too much! If you aren’t blessed with green fingers and are absent-minded about watering and caring for your houseplants, this resilient plant is definitely for you. Yucca plants grow slowly and can grow as high as 10m in height, producing impressive green sword-like leaves that can be a real showstopper. One of the first signs that something is wrong with your yucca plant is if you notice those gorgeous green leaves starting to turn yellow. In this article, we will look at all the reasons why your yucca plant is yellowing and what you can do to fix it. 1) Overwatering Perhaps the most common cause of yellow leaves on yucca plants is down to overwatering. Watering your plants too much or too often will lead to root rot. Be sure to plant your yucca in sandy, well-draining soil so that the water drains easily and the soil doesn’t stay wet for too long. You should also avoid using organic mulch so excess moisture is not retained at the roots. 2) A Lack Of Light Another common reason for a yellowing yucca is insufficient light. Yuccas are used to hot, dry, and even arid conditions in full sunlight, so you really need to find a spot where your plant can benefit from as much light as possible. Ideally, your yucca should be placed in direct sunlight where it can receive light all day long. South-facing windows will usually be best for this. “If planting on a south-facing windowsill, make sure to monitor compost moisture regularly as in hot weather it may dry out very quickly,” says Master Horticulturist Colin Skelly. “Temperatures will fluctuate rapidly, so keep an eye on your Yucca when first putting it in position and move it to a west or east-facing window if leaves start to yellow as this may provide still bright but more stable conditions. “The RHS recommends a south-facing window in winter and east or west facing windows in summer.” 3) Pests Yucca plants are actually usually pretty pest-free, however, you may occasionally encounter spider mites which will cause the leaves to yellow. Thankfully, spider mites are easy to get rid of. Simply wipe down the leaves every couple of days with a wet cloth and the problematic pests should disappear. Alternatively, you can pop the plant under a shower or sink to wash the bugs away. 4) Old Age With age, the yucca’s leaves may begin to yellow. All you need to do is gently remove the yellowing leaves, making way for fresh new green ones to appear. As you can see, there are plenty of solutions for yellowing yuccas and, by following this advice, you will be able to enjoy your happy and healthy yucca for many years.
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