Growing
Make Sure You Plant Eucalyptus In Full Sun With Enough Room, Says Horticulturist
IN THIS GUIDE Overview Planting Eucalyptus Eucalyptus Tree Care Common Types References Ranging in size from small shrubs to tall trees, eucalyptus is an evergreen plant hailing from Australia which is commonly associated with its native country and the koala bears who feast upon it. But despite having their roots down under, these impressive specimens have taken to the British climate remarkably well and most varieties available on home shores are considered fairly hardy. They’re a popular choice with gardeners up and down the country for their bluish-grey bark, which peels away in strips to reveal a startling yellow beneath, as well as their blue-green foliage. Their leaves exude a distinctive scent when crushed. Overview Botanical Name Eucalyptus Common Name(s) Gum Tree Plant Type Tree / Shrub Native Area Australia Hardiness Rating H5 (varies by type) Foliage Evergreen Flowers Cone-shaped and grouped together in threes When To Plant May-September When To Prune February-March Planting Eucalyptus Most varieties of eucalyptus require plenty of time to establish themselves before the colder temperatures set in, so planting in spring or summer is recommended. However, there are certain species, such as E. coccifera (or the Tasmanian snow gum) which prefer planting later in the year in September, October and November. If in doubt, check the planting instructions with the nursery or vendor. Positioning Eucalyptus are generally quite forgiving of soil types, as long as the terrain drains effectively. However, they do demand full exposure to the sun and appreciate some shelter from the wind, so a spot next to a fence or wall might be ideal. Most eucalyptus species do perfectly well in pots and containers, too. While a certain degree of care and maintenance will be required in the first few years after planting in order to allow the tree to establish itself in the ground, they can largely be left to their own devices afterwards. Pruning, coppicing and pollarding are all viable means of altering the shape and size of the tree as it develops, though none are essential if the location and conditions in which it is planted are satisfactory. “I have come across many eucalyptus trees that have been planted in positions that are too small for the eventual size of the tree,” says Horticultural Consultant Colin Skelly. “Many species grow very quickly and dominate a space. Coppicing and pollarding are a really good way to retain the tree whilst allowing in more light and moisture. “The juvenile leaves of the new foliage are also very attractive.” Shade Growing Although eucalyptus is a fairly undemanding plant, its one prerequisite for healthy growth is full sun exposure. As such, they are not well suited to growing in the shade. Having said that, there are certain eucalyptus cultivars which can handle partial shade better than others. These include E. crenulata and E. neglecta – but even so, both of these cultivars will require at least some sunlight. Planting Out Plant your eucalyptus in a hole that’s slightly bigger than the root ball, taking care not to disturb the roots when doing so. If planting seeds, use root trainers to establish them initially, before transplanting them into their final position no later than midsummer. Bear in mind the potential height and spread of the species you possess, planting the root ball at an appropriate distance from other plants or buildings to allow for their development. In general, it’s advisable to opt for smaller cultivars, since they will establish themselves more quickly and easily and won’t pose problems in their later life. Eucalyptus does not require enrichment of the soil by manure, since this will only encourage an excess of leafy growth. However, they do appreciate mulching of organic matter around (but not directly next to) the trunk, as well as regular maintenance to rid the area of weeds for the first few years. Supports are to be actively discouraged, since cultivating eucalyptus without the aid of them will instigate stronger root growth. Eucalyptus Tree Care Once established, eucalyptus trees require very little in the way of upkeep. However, very young specimens will certainly benefit from a helping hand, even for several years after their initial planting. Light Exposure to full sun is a must throughout their entire lifespan for most eucalyptus species. Soil As long as good drainage is guaranteed, eucalyptus trees aren’t fussy about the soil beneath their feet. Mulching is recommended for the first few years of their life, but the use of manure is overkill and will result in overly leafy growth. Water Water the seeds or root ball well to facilitate the settling-in process. Until the tree has firmly taken root after a couple of years, watering should only be necessary during dry spells and not at all thereafter. Temperature & Humidity Most varieties of eucalyptus that are cultivated in the UK are fairly resilient against the elements and won’t require mollycoddling during the winter months. Having said that, if your tree is planted in a pot, you might want to move it to a warmer area when the mercury drops. Rather than temperature or humidity, the biggest consideration to keep in mind is waterlogged soil. If your part of the country is particularly prone to excessive rain or snow during winter, you might want to shelter it from the worst downpours. Potted specimens can be raised up on bricks to keep drainage holes clear. Pruning Generally speaking, there’s no need to prune eucalyptus trees, since they are more than capable of looking after themselves. However, those growing the species for ornamental reasons may wish to prune it in order to prevent foliage from reaching maturity, since the juvenile form of the leaves is often considered more attractive. Initial pruning at the beginning of the plant’s life can also be beneficial in shaping its growth. Similarly, you might wish to prune larger species to prevent them from becoming too big for their environs. This can easily be achieved by coppicing or pollarding in springtime. It should not be practised more regularly than every couple of years. Common Types There are over 700 varieties of eucalyptus found in the plants that are native to Australia, but just 15 of those grow outside its borders.1 Here are two of the most popular and commonly found varieties in the UK, both of which have received the RHS Award of Garden Merit (AGM) and can be readily purchased at garden centres around the country: Eucalyptus dalrympleana Capable of growing up to 15m in height and around half of that in spread, E. dalrympleana (or the mountain gum tree, as it is more commonly known) is a fast-growing evergreen tree. It’s instantly recognisable by its grey-white bark which flakes away freely, as well as its drooping, narrow, grey-green leaves. Younger leaves carry a copper tint, while white flowers appear in summer and autumn. Eucalyptus gunnii Also known as the cider gum tree, E. gunnii is slightly larger than E. dalrympleana. It can grow up to 25m in height and 10m in spread, with its peeling cream and brown bark a common sight around the UK. Its foliage begins life rounded and bluish, before developing a thinner and greyer form as it grows. Tightly bunched clusters of small white flowers appear in the summer. References 1. Eucalyptus. (n.d.). Botany Bay Learning Resources. Retrieved March 15, 2023, from https://originsfestival.bordercrossings.org.uk/sites/default/files/2022-05/Eucalyptus.pdf
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Ash Dieback Is Now Very Widespread: Play Your Part In Helping To Tackle The Problem
IN THIS GUIDE What Is Ash Dieback? About Ash Trees Identifying Ash Dieback When To Look Out For Symptoms Reporting Ash Dieback Slowing The Spread Do Trees With Ash Dieback Need To Be Felled? References British ash trees are one of our most important native trees, but unfortunately, ash trees are threatened by a fungal disease called ash dieback. Learn more about this issue and what can be done to slow its spread and deal with this issue in this guide. Ash dieback was first found in the UK in 2012 and is now very widespread.1 It poses a threat to ash trees growing in parks and gardens and to natural woodlands and forests. Gardeners can play their part in helping to tackle this serious problem, by taking measures to help slow its spread in affected areas, and by reporting dieback in parts of the UK where it has not already been recorded. Learning more about this problem and how to identify it is the first step in learning how to help. What Is Ash Dieback? Ash dieback, also called Chalara dieback to set it apart from other causes of dieback in ash trees, is a highly destructive disease of ash trees, especially our native common ash, Fraxinus excelsior. The cause of this disease is a fungus called Hymenoscyphus fraxineus, which originated in East Asia.2 This disease is now found in most areas of the UK, though its effects are clearest and most noticeable in those regions of the country in which the fungus was present earliest, and where local environmental conditions allow the fungus to thrive.3 In the UK, the disease was confirmed first in trees growing in nurseries or on recently planted ash trees. However, many cases have now been found in the wider environment. This disease is also established in many other European countries, where it has had devastating effects. As well as affecting our common ash, this disease also affects many other varieties. In 2018, ash dieback was also found on three other ornamental tree and shrub species: mock privet (Phillyrea latifolia), P. angustifolia and Chionanthus virgincus.4 Ash dieback on common ash does have a significant threat to woodland ecology and biodiversity. It also has major impacts on the forestry and hardwood industries. Older trees can survive for some time, but can succumb when exposed for longer. They may also be hit in their weakened state by another pathogen, like honey fungus, which can eventually kill them. About Ash Trees Common ash makes up 12% of the broadleaf woodland of the British Isles and is also common in parks, gardens, hedgerows and roadsides.5 A huge variety of native wildlife benefits from it, and it grows in a wide range of soils and climates. Due to their light and open canopies, ash trees also increase and encourage biodiversity on woodland and forest floors. Ash is also a very important species for its timber, which is used for many different purposes. and some types are quite popular for garden and ornamental use. Identifying Ash Dieback The symptoms of this disease can be seen on the leaves, the stems and on the tree as a whole. Leaves will often begin to turn black, often first blackening along the midrib and leaf base. The leaves which are affected will also wilt. On stems, small lesions or spots will appear on the bark and these can grow to form cankers. In some cases, the disease may circle the stem and kill it in a single season. When the bark is peeled off, the brownish or grey discolouration can be seen, which extends beyond the area of dead bark. Trees that are infected show extensive dieback of branches, shoots and twigs. Often, many shoots which are produced from previously dormant buds can be seen. When To Look Out For Symptoms The optimal time to identify ash dieback is between July and September when blackening and wilting are likely to be seen, and natural seasonal changes will not be mistaken for indications that the disease is present. Some other things that are normal for ash trees are sometimes mistaken for indications of this problem but are not indicative of the disease. Firstly, note that ashes are one of the latest trees to produce new leaves in spring. Often, late flushing may cause people to suspect that the tree is dead or dying, but ash trees may not be in leaf until June. It is only when we reach mid-June that lack of leaves would be a concern. By then, all healthy ash trees are in full leaf. You may also see dark ash keys on the tree after the leaves fall in autumn. These are normal things for ash trees, but people sometimes think they are blackened leaves from a distance. Reporting Ash Dieback Forest Research and country forest authorities want to get reports of chalara ash dieback in areas where it has not yet been reported.6 Ash dieback in Great Britain should be reported through TreeAlert, and ash dieback in Northern Ireland through TreeCheck; both are branches of the gov.uk website.7 These sites require you to upload clear and close-up pictures of the tree’s symptoms. In some cases, you may then be asked to provide more information, and further investigation of the tree in question may be arranged in some cases. Slowing The Spread Ash dieback spreads through spores of the fungus, which can be carried locally for many miles on the winds, but sometimes can even be carried from mainland Europe.8 Government scientists have also concluded that spores only live for a few days, spores come from infected dead leaves between June and September, and that there’s a low chance of dispersal on clothing, or animals and birds.9 Individuals can help slow the spread of ash dieback in areas where the disease is present by making sure that they brush soil and plant matter off their shoes, wheels and clothing before leaving a woodland site – washing these items before they visit another site.10 Car drivers are urged to park on paved areas where possible when visiting woodland sites, and cyclists are asked to wash down bikes before and after taking woodland or forest trails to avoid accidentally spreading chalara ash dieback. Gardeners can also help slow the spread of ash dieback in their area by collecting and deep composting the leaves to prevent the spores from being dispersed and disrupting the fungus’ life cycle. Infected leaves should be covered with 10cm of soil or 15-30cm of other organic matter. The area should then be left undisturbed (other than adding more material on top) for at least a year. “If you are considering getting bark chips from a tree surgeon to help control the spread of tree pests and diseases, it would be wise to ask for no chip from diseased Ash or Elm trees,” adds Dan Ori, Master Horticulturist. Do Trees With Ash Dieback Need To Be Felled? If you have an ash tree in your garden suffering from ash dieback, you may wonder whether it needs to be felled. In most cases, it is best to keep your tree standing if you can, even if it is infected. Tree preservation orders must also still be respected.11 Most trees infected with this disease will sadly die, but scientists have found that a small number ash of trees can tolerate infection.12 A proportion may also become symptomatic but then regain their good health. It is not yet known whether such trees are to be found in the UK ash population, but keeping trees standing is invaluable for research. It may be that tolerant trees can potentially be utilised to breed more tolerant trees for our future. However, safety is a priority, so it is important to observe your ash tree very carefully as the disease proceeds. It may have to be felled if branches look like they are likely to break off and cause damage or injury, or if the trunk is weakened near the base and the tree may fall more easily. Ash dieback is a large ecological problem, but there is hope. Work is being done to selectively breed tolerant trees to replace the ash trees that are lost and gardeners can help by reporting this when it spreads to new areas, and by helping to slow the spread of the disease by managing diseased leaves in their gardens. References 1. Forest Research. (2022, December 13). Ash dieback (Hymenoscyphus fraxineus). Retrieved March 9, 2023, from https://www.forestresearch.gov.uk/tools-and-resources/fthr/pest-and-disease-resources/ash-dieback-hymenoscyphus-fraxineus/ 2. Nielsen, L. R., McKinney, L. V., Hietala, A. M., & Kjær, E. D. (2017). The susceptibility of Asian, European and North American Fraxinus species to the ash dieback pathogen Hymenoscyphus fraxineus reflects their phylogenetic history. European Journal of Forest Research, 136(1), 59–73. https://doi.org/10.1007/s10342-016-1009-0 3. Ash Dieback UK Outbreak. (n.d.). Forestry Commission. Retrieved March 9, 2023, from https://cdn.forestresearch.gov.uk/2022/02/ashdieback_uk_outbreak_map4_10_web_version_may2020-scaled.jpg 4. Better, F. G. C.-. B. L. L. (2018, August 29). Ash dieback alert. Frosts Garden Centres. Retrieved March 9, 2023, from https://www.frostsgardencentres.co.uk/news/24/ash-dieback-alert 5. Forest Research. (2022a, February 16). Woodland area by species. Retrieved March 9, 2023, from https://www.forestresearch.gov.uk/tools-and-resources/statistics/forestry-statistics/forestry-statistics-2018/woodland-areas-and-planting/national-forest-inventory/woodland-area-by-species-broadleaves/ 6. How to report Ash Dieback. (n.d.). Cornwall Council. Retrieved March 9, 2023, from https://www.cornwall.gov.uk/environment/trees-hedges-and-woodlands/tree-and-woodland-management/how-to-report-ash-dieback/ 7. Report a tree pest or disease. (2018, September 26). GOV.UK. Retrieved March 9, 2023, from https://www.gov.uk/guidance/report-a-tree-pest-or-disease-overview 8. Trust, W. (n.d.-a). Ash Dieback (Hymenoscyphus fraxineus). Woodland Trust. Retrieved March 9, 2023, from https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/tree-pests-and-diseases/key-tree-pests-and-diseases/ash-dieback/ 9. Managing ash dieback in England. (2021, June 10). GOV.UK. Retrieved March 9, 2023, from https://www.gov.uk/guidance/managing-ash-dieback-in-england 10. The Tree Council. (2022, July 12). Ash dieback action plan toolkit for local authorities. Retrieved March 9, 2023, from https://treecouncil.org.uk/what-we-do/science-and-research/ash-dieback/local-authority-ash-dieback-action-plan-toolkit/ 11. Ash dieback. (n.d.). Broads Authority. Retrieved March 9, 2023, from https://www.broads-authority.gov.uk/planning/other-planning-issues/trees-and-hedgerows/ash-dieback 12. Ash Dieback Disease: A Guide For Tree Owners. (n.d.). The Tree Council. Retrieved March 9, 2023, from https://treecouncil.org.uk/wp-content/uploads/2020/06/Tree-Council-Ash-dieback-tree-owners-guide-FINAL.pdf
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Growing Quince: How To Plant A Tree From A Pot-Grown Or Bare Root Specimen
IN THIS GUIDE Overview Quince Trees Bare Root Vs Pot Grown Where To Plant How To Plant Quince Ongoing Tree Care Common Varieties References Quince fruit is excellent for making tartly flavourful preserves and confections, but did you know that the fruit of some cultivars is a mellow and delicious treat to eat raw? As for the quince tree, I’ve found that it is a joy for a gardener to tend to. It is truly ornamental, as it is proportionately branched with lovely rich green foliage and delicate pink blossoms. “My favourite plant changes everyday, but one that I couldn’t do without would have to be a quince tree,” shares Landscape Architect Bunny Guinness. Overview Botanical Name Cydonia oblonga Common Name(s) Quince Plant Type Perennial Tree Native Area Central Asia Hardiness Rating H5 Foliage Deciduous Flowers Delicate, white and pale pink cup-shaped flowers When To Plant February to November Harvesting Months September to November If you’re looking for a curious fruit, you’ve found it in quince. The fruit is usually pear-shaped, but can sometimes appear roundish – rather like an apple. This is not surprising because, like both pears and apples, quince is a pome. Once ripe, the fruit is golden yellow. Though deliciously aromatic and tartly flavourful, quince is infrequently enjoyed raw.1 It is more often used as the main ingredient in a wide range of foodstuffs, such as preserves, jams, sauces, pastes, and confections in many regions of Europe and Asia.2 Quince is even used in pot-cooked foods and as a savoury ingredient in some Mediterranean cuisines. The fruit-bearing Quince Tree is the only member of Genus Cydonia.3 There is also a ‘false’ Quince Tree, Pseudocydonia sinensis, whose fruit is also used to make jams and preserves. Complicating things further is the ‘Flowering Quince’ that belongs to the genus Chaenomeles. This is a marvellous flowering hedge or wall shrub that also produces fruit, and though it technically can be made into jams and preserves, it is neither as flavourful nor as desirable as the real quince fruit. Quince Trees Quince trees are pretty and, though on the small side, must be recognised as being ornamental trees and even landscape trees in their own right. Correctly pruned, the mature tree is proportionately and finely branched and has a good spread with a willowy, pendulous quality to its limbs. The tree progressively becomes gnarly, so it’s no wonder that it is a bonsai favourite. Quince trees also come in dwarf sizes that grow to no more than a metre. These patio trees are ideal for container growing. Standard-size trees, planted outdoors, are typically about 3m high, but can grow up to a height of 4m. Since quince trees are self-fertile, in theory you need only one tree for it to bear fruit.4 However, these trees will bear a bountiful crop only when they are cross-pollinated, so consider planting two or three. Apart from autumn fruit, quince trees also serve up other joys. In late spring and early summer, the delicate pink-tinged, cup-shaped blossoms decorate an already pretty tree, while the foliage is that just-right shade of rich, green that brings a soothing, cooling quality to the garden. Bare Root Vs Pot Grown Quince trees are divided into two kinds; proper free-standing trees and patio trees that are meant for container growing. The former typically reach an ultimate height and spread of 4-5m while the latter typically grow to only about 1m in height. Standard full-size trees of about 2 years in age are just as often sold in bare-root form as in pot-grown form, whereas patio trees are usually sold in pots. Though you can buy any of these variants, there are a few subtle dos-and-don’ts to bear in mind. Bare-root trees are available during the November-January timeframe and should be planted promptly, whereas potted quince trees of either size are available year-round and, though they may be transplanted during any season, the best period to transplant them is whilst they are dormant. Where To Plant Though quince trees, with a hardiness rating of H5, are hardy throughout the United Kingdom, the flowers are prone to frost damage. In addition to this, it’s important to note that the warmer the summers, the better the fruit. Therefore, they should be planted in full sun and in a sheltered location. Avoid positions facing directly to the east, where rapid frost thawing damages blossoms and young fruit. Full-size trees should be planted in the open ground while patio trees will thrive in large containers of about 60cm. These trees will do very well planted close to a pond or brook so long as the soil does not stay very damp in the winter. They should be planted during dormancy which is from December and January, perhaps February. Soil Requirements Quince trees grow well enough in most kinds of soil but in order for the tree to flourish and produce a rich yield year after year, grow it in optimal soil conditions. A fertile soil of a heavyish loam amended with an ample quantity of organic material such as humus, compost and/or well-rotted manure is ideal. The lighter and poorer the soil, the more generously it should be amended with this type of organic content. Though such a soil will retain moisture, it should drain well, especially in winter. This is why quinces grow well on sandy soils, and why heavy clays will not be suitable. The soil should be kept moist during the growing season. A soil pH that is slightly acidic to neutral will work best. Sunlight Along the southern coast of the United Kingdom and in the less cold regions, quince trees may be planted in an exposed location without concern for aspect. In other regions, they should be sited in a sheltered location protected from northerly winds. A south-west-facing corner is ideal. Spacing Quince trees from the smallest container trees to full-size standards have very different spreads. A good rule of thumb is to space a tree by twice its eventual spread, or two different varieties by the sum of their spreads. How To Plant Quince To get the best out of your quince tree throughout its long life, follow the planting steps below: Select a site that conforms with what is described in the preceding sections. Prepare a planting hole that is as deep as the container the young tree is in and twice or thrice as wide. Remove the tree from the container and immerse the root system in a pail of water for five to ten minutes. Ensure that the tree is not root-bound; the rootball should be loosened and the roots should spread out. Place the tree in the planting hole such that its soil line will be the same as it was in the container. The soil should not reach up to any part of the main stem that was not previously in the soil. If the tree is sitting deeper in the hole, fill it in a little before planting. Young quince trees need support. This is accomplished by way of one or two stakes at an angle in the ground. The stake(s) should be at about a 45° angle, propping up the main stem or nascent trunk, and avoiding the roots. Backfill the hole and pack the soil all round. Water freely. Add a layer of mulch of up to 8cm around and over the root system (though it must be 8-10cm away from the main stem). Ongoing Tree Care Quince trees need regular watering during the growing season. Whilst establishing, water freely and deeply once a week and make sure the soil doesn’t dry out during dry spells in summer. Soil in containers will not retain moisture as much as open ground, so pay particular care to water container-grown trees. Quince tree containers must have drainage holes. During winter dormancy, the soil should not remain very damp wherever it is grown. Feeding Quince trees in open ground may be fed in winters-end or early spring. Use a granular high-potash fertiliser and sprinkle it around the tree, about 8cm away from the trunk. Container-grown trees should be fertilised every month during the growing season. For these, use a liquid high-potash fertiliser at the appropriate dilution. Do not use a high-nitrogen fertiliser or a balanced fertiliser and avoid over-fertilising. Common Pests & Diseases Quince trees may sometimes be affected by powdery mildew and brown rot, which luckily can be controlled by the average gardener. Quince leaf blight and fireblight are two other diseases that can strike quince trees and these are much more problematic. Quince leaf blight is a very serious fungal disease but it can be treated with chemical fungicides. Any fruit from a tree so treated must not be eaten and should be destroyed. Fireblight is even more destructive. It is a bacterial infection that spreads all through the tree, and unfortunately only an experienced tree doctor has any chance of saving a tree affected by this deadly disease. Protecting From Frost Quince trees bear flowers in early spring and the flowers can succumb to frost. As such, if you live in a cold region where spring frost is predicted, it would be advisable to try to cover as many buds and flowers as possible with horticultural fleece in the evening. Complicating the chore, the fleece should be removed in the morning to allow both sunlight and pollinators to reach the flowers. Propagating Professional growers usually produce Quince trees for the market by grafting. They are also propagated from hardwood cuttings. Amateur gardeners can fairly easily propagate them by taking and rooting hardwood cuttings in late autumn and early winter, and from greenwood cuttings in the summer. Take a 15cm cutting of non-fruiting growth, remove all but 2-4 leaves, dip the base in rooting hormone, and insert the cutting into a pot filled with potting mix or a mix of light soil and organic compost. Place the pot in a sunny location and keep the soil damp. In dry conditions, cover the cutting with perforated plastic film, but be sure that it doesn’t stick to the cutting. How Long Does It Take For A Quince Tree To Bear Fruit? The ‘right’ answer is 4 years, and this holds good for the common quince tree. The real answer is that it depends on the rootstock and the cultivar, and can vary from 2-6 years. As a rule, I’ve found that this tree will start to produce high-quality fruit and high yields about 3 years after its first production of fruit. “The fragrance of the fruit is what really blows me away about quinces,” shares Peter. “Sadly, ours has become a biennial bearer, which can happen to some trees where, with age, they crop well only every other year. Steps can be taken to address this, such as thinning blossoms and fruits in heavy cropping years.” Harvesting & Storage Different varieties’ fruit is ready to harvest at different times in autumn from September to November. Common quince fruit is usually ready to be picked in October when it is a golden-yellow hue. No matter which variety, the longer the fruit is left on the tree, the richer and more well-developed the flavour. With this in mind, delay harvesting the fruit for as long as you can. Harvest the fruit when there is a chance of frost, especially for cultivars like ‘Aromatnaya’ and ‘Kuganskaya’. Store undamaged fruit in a dark and cool room on a flat surface without stacking and without the fruits touching. Though the fruit of the common quince can be stored for 8-12 weeks, I have found that they will be just right for preserves, confections, and other cooking in 6-8 weeks. Common Varieties “Whenever choosing a fruit tree, make sure to check the rootstock if you can,” says Master Horticulturist Peter Lickorish. “This is the plant which donates its roots to your chosen variety when the two are grafted together. “Quince A is a rootstock producing a larger tree, whilst Quince C and ‘Eline’ produce smaller trees. Quinces are also used as the rootstock for most pear trees.” Cydonia oblonga, otherwise known as the common quince, is the species tree. The species flowers in late spring and bears fruit in around October. The ripe fruit is of a golden-yellow colour and is lumpily pear-shaped. ‘Serbian Gold’ ‘Serbian Gold’ is one of my favourite cultivars which, while it is not known for its vigour, is renowned for its good cropping and relatively early fruiting and consequent harvesting which is in late September. The fruit is similar to the species but rounder, and it too is not meant for consuming raw. It grows to a mature height of up to 4m and has received the RHS Award of Garden Merit. “‘Serbian Gold’ is my favourite variety of quince because it is resistant to the blight that some others are affected by,” shares Bunny. This cultivar is also available on semi-dwarfing rootstock; such a patio tree will attain a height of only 1.5m and is ideal for a container on the patio. ‘Vranja’ ‘Vranja’ is a popular variety in the United Kingdom. It is similar to the species but is a late-fruiting variety, cropping in November or even December. ‘Aromatnaya’ ‘Aromatnaya’ is an Eastern European cultivar and is less commonly grown here in the UK. It is a very prolific variety and bears its fruits earlier than other varieties. Unfortunately, this tree is more susceptible to fireblight than other varieties. ‘Kuganskaya’ Sometimes referred to as Russian Quince, this cultivar actually hails from Armenia rather than Russia, and is a rare find in the UK. It has average productivity and bears fruit in mid-autumn. Chaenomeles japonica This flowering quince is not a Quince tree, looks very different, and has somewhat different growing and care guidelines, but is mentioned here for completeness and because it is very commonly grown in the United Kingdom. Its fruit, though edible, cannot even compare with the Quince tree cultivars listed above. It is a spreading bush or hedge that grows to only about 1m, with a spread of about 1.5m. It is a striking sight in early spring as it bears copious bunches of bright vermilion or scarlet cup-shaped flowers. Pseudocydonia sinensis This plant is also not a traditional quince tree, looks very different, and also has somewhat different botanical characteristics but, like Chaenomeles japonica, is mentioned here for completeness. It is a bushy shrub whose true value lies in its beauty. It has highly textured, mottled bark and dark green leaves that have a glossy sheen which put on a colour show in the autumn before shedding. In spring it is covered in a bloom of fragrant reddish-pink cup-shaped flowers. References 1. Hill, A. (2019, October 1). 8 Emerging Health Benefits of Quince (And How to Eat It). Healthline. Retrieved March 23, 2023, from https://www.healthline.com/nutrition/what-is-quince-fruit 2. Quince. (2020, August 11). BBC Good Food. Retrieved March 23, 2023, from https://www.bbcgoodfood.com/glossary/quince-glossary 3. Harris, S. (n.d.-a). Cydonia oblonga. Oxford University Plants. Retrieved March 23, 2023, from https://herbaria.plants.ox.ac.uk/bol/plants400/Profiles/CD/Cydonia 4. Pollination of apple trees and other fruit trees. (n.d.). Orange Pippin Fruit Trees (UK). Retrieved March 23, 2023, from https://www.orangepippintrees.co.uk/articles/planting-and-growing/pollination-of-fruit-trees
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How To Grow A Birch Tree - 'A Good Choice For Even The Smallest Of Gardens'
IN THIS GUIDE Overview Why Grow A Birch Tree? Birch Varieties Where To Grow Planting Birches Birch Tree Care References Birch trees are beautiful native trees which can find a place in many UK gardens. They have simple leaves, often borne in pairs on two-leaved lateral branchlets. “Birch can get quite tall, but it isn’t a dense tree, so it won’t feel too big and its roots won’t spread too much, making it a good choice for even the smallest of gardens,” shares Ben Raskin, an award-winning Horticulturist. Overview Botanical Name Betula Common Name(s) Birch Plant Type Tree Native Area United Kingdom Hardiness Rating H7 Foliage Deciduous Flowers Catkins When To Plant Autumn and Winter When To Prune Late Summer Birches are deciduous hardwood trees in the Betula genus. The Betula genus is in the Betulaceae family, which also includes hazels, hornbeams and alders.1 There are between 30 and 60 known taxa within this genus. Unlike with alders, the catkins borne on the trees in spring are not woody and break apart at maturity to release their seeds.2 There are two main species of birch native to the British Isles, which we will look at in more depth below. There are also a number of non-native species which are often grown as garden trees here in the UK. Why Grow A Birch Tree? Birch trees are wonderfully ornamental trees to consider growing in your garden. They are attractive all year round, with interest from the bark and form, catkins in spring, and often good autumnal foliage colouration too. Beyond aesthetic concerns, however, birches can be good choices for a wildlife-friendly, eco-friendly garden. These are relatively short-lived pioneer species, which often colonise new areas, creating ecosystems where a range of other plant and animal life can thrive.3 In the wild, birch woods have an open canopy, allowing bluebells, grasses, mosses, violets, wood anemones, wood sorrel, and other woodland species to grow.4 This light-open canopy can also be useful in a garden, allowing for layered planting below the trees, or for the creation of a more naturalistic woodland scheme. Root action of birches can aid in improving the soil and benefiting other plants growing nearby. The leaves make good compost and enrich humus on the soil surface when left to decompose. Native birches provide food and habitat for over 300 different insect species, and the aphids and other insects that are attracted to these trees bring, in turn, a range of other species, like ladybirds, which prey on them to your garden.5 The leaves of birch trees are also food for the caterpillars of many moth species. Birch trees are also great for birds. Woodpeckers and other hole-nesting birds may often make their nests in the trunks of birch trees, and the seeds attract and are eaten by species including greenfinches, siskins and redpolls. Another thing to note is that birch trees can provide a range of useful yields. Pruned materials of this hardwood have a range of interesting uses in crafts and the trees can potentially be coppiced for a range of uses too. Birch trees are sometimes tapped to collect their sap which makes a refreshing drink, which can also be boiled down to concentrate it into syrup. Young birch leaves can also be eaten, raw or cooked.6 Birch Varieties The best birch trees to consider for UK gardens are native birches, which bring benefits for a range of wildlife and provide habitat for a range of native species.7 The two common native species in the British Isles are the silver birch and the downy birch: Silver Birch – Betula pendula The Silver Birch is an extremely popular garden tree. It can grow up to around 30m in height and 4-8m wide, and is prized for its attractive and light canopied form, and beautiful papery white bark which sheds in layers and develops interesting patinas as the trees mature. Attractive yellowish catkins appear on the trees during the spring and, like other birches, foliage can colour well in the autumn months. “I wouldn’t be without silver birch in my garden,” shares Nic Wilson, a Garden Writer. “Ours attracts so many birds to the garden and over 300 insect species have been recorded living or feeding on birch. Like many trees, it’s an ecosystem all of its own.” Downy Birch – Betula pubescens The downy birch is a broadleaf species which grows further north than any other. Also known as the European White Birch, White Birch, or Hairy Birch, mature trees of this species can also grow up to 30m tall and 4-8m wide. They have somewhat brownish leaves, without the Silver Birch’s paperiness, and with more obvious horizontal grooves, and form a light canopy with elegant and drooping branches. The name comes from the downy texture of the leaf stalks, which is not found on silver birches. Like the above, the downy birch bears yellow-brown catkins in spring and can have good autumn colour. Non-Native Birches However, while planting native trees is often the best option for eco-friendly gardens, there are also a range of other birches which can be excellent choices for ornamental appeal. “Since the UK experienced glaciation relatively recently, its flora is relatively sparse compared to areas of the world that did not,” shares Colin Skelly, a Master Horticulturist. “Utilising near-native (European or North American) or exotic (southern hemisphere) plants extends to the range of plants available to gardeners and is still often a resource for wildlife.” Some non-native birches often chosen for UK gardens due to their ornamental appeal include: Paper Birch (B. papyrifera) Himalayan Birch (B. utilis) Gold Birch (B. ermanii) Gold Bark Birch (B. medwediemii) “I absolutely love growing Betula utilis,” shares Garden Designer Jacquie Felix-Mitchell. “This Birch is such a beauty, with a fabulous sense of the ethereal in the winter garden.” There are examples of all the above which can make great choices, even in smaller gardens. Where To Grow Silver birches and white birches both look particularly pleasing when planted in small groups or when cultivated/coppiced as multi-stemmed examples. Native birch trees prefer a well-drained and fertile loam in a sunny position. They will not grow well in the shade, but can tolerate almost all soil conditions, including poor soils, sandy soils, and heavy clays. The native birches usually prefer acidic or neutral soil but can also often grow well in alkaline conditions. Birches are also fully hardy (H7) and can cope with a fairly high degree of wind exposure. Native birches can be placed on a lawn as specimen trees, form the canopy in a woodland area or forest garden, or even be placed towards the back of garden borders, surrounded by shrubs and herbaceous planting. Planting Birches Birch trees can be purchased as saplings or more mature specimens. These can be purchased as bare root plants over the dormant period (generally the more affordable option) or as pot-grown specimens throughout the rest of the year. Planting can be done at any time, but it is best to avoid the warmest summer months when transplantation may be trickier and the plants may put be under more stress due to the temperatures and dry conditions. Dig generous planting holes large enough to accommodate the root systems of the new trees, adding a layer of compost or other organic matter to the planting hole before you plant your tree. Place the rootball in your planting hole, making sure that the tree is planted to the same depth. Fill back the soil around the tree and water it in well; add a generous mulch of organic matter around the tree. Birch Tree Care Watering Water your birch trees well until they become established, after which time, when they are well-rooted, natural rainfall should be sufficient. Feeding Additional feeding is not required, but it is a good idea to replenish the organic mulch around the base of your birch trees each spring. Pruning Birch trees should absolutely only be pruned when fully dormant between early autumn and the middle of winter. Pruning at any other time will make the trees bleed sap heavily, even in late winter when the sap of other trees may not have yet risen. Established trees do not need regular pruning, and hard pruning is not recommended. However, removing damaged wood, or crossing branches can be beneficial (and these may be useful for a range of projects too). If you wish to make a multi-stemmed birch, choose a young plant no more than around a metre tall and cut it horizontally close to ground level (at around 10cm) or to around 30-60cm or so above the ground. This cut should stimulate dormant buds which will grow up strongly the following year. After a couple of years, you may wish also to restrict the number of main stems by choosing a few well-spaced ones to keep, cutting out the rest down to the base. Bark Care Many birches are chosen for their attractive peeling bark, but if some loose bark is getting a little tatty, you may remove some of it. Just make sure that you do not remove too much, or go too far, as this may damage the living tissues of the tree just below the surface. If you wish to show off pale-coloured bark to best effect, you can clean off some green algae from the main trunk with a soft, wet cloth. This won’t harm the tree and the algae will quickly return. However, make sure that you don’t disturb the lichens and mosses which may grow from outlying branches, as these are a crucial part of your garden’s ecosystem. Birch trees make wonderful additions to a healthy, productive and beautiful garden, so you should definitely consider growing at least one where you live. References 1. Betulaceae (birch family). (n.d.). Native Plant Trust. Retrieved March 9, 2023, from https://gobotany.nativeplanttrust.org/family/betulaceae/ 2. How to identify the Silver birch tree (Betula pendula) in a few easy steps. (n.d.). The Conservation Volunteers. Retrieved March 9, 2023, from https://treegrowing.tcv.org.uk/identify/silver-birch 3. Birch. (n.d.). Future Trees Trust. Retrieved March 9, 2023, from https://www.futuretrees.org/birch/ 4. Trust, W. (n.d.-c). Silver Birch (Betula pendula). Woodland Trust. Retrieved March 9, 2023, from https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/british-trees/a-z-of-british-trees/silver-birch/ 5. Birch. (n.d.-b). Guide to Insect Pests of Woody Plants. Retrieved March 9, 2023, from https://www.uky.edu/Ag/Entomology/treepestguide/birch.html 6. H. (2020b, April 9). Birch, Extremely Versatile with a Tasty Wintergreen Flavoring. Eat the Planet. https://eattheplanet.org/birch-extremely-versatile-with-a-tasty-wintergreen-flavoring/ 7. UK Native Trees. (n.d.). Woodland Trust. Retrieved April 25, 2023, from https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/british-trees/native-trees/
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Crab Apple Trees Work In Most Gardens - Horticulturists Share Their Growing Tips
IN THIS GUIDE Overview Crab Apple Varieties How To Grow & Care For Crab Apples Planting Pruning Common Problems References Crab apple trees are ideal for most gardens because they not only look great almost all year round with their spring blossom and autumnal foliage but they produce colourful fruit that can be used for delicious recipes. As a relatively small tree, crab apples are a great way of bringing some height and structure into a garden and are a haven for wildlife as well. Part of the Rosaceae family, crab apples are hardy and deciduous trees that are relatively small depending on their actual variety. Overview Botanical Name Malus Common Name(s) Crab Apple Plant Type Fruit Tree Native Area Asia Hardiness Rating H6 Foliage Deciduous Flowers Pink and white clusters When To Plant Winter When To Harvest Autumn When To Prune Winter They are not to be confused with our sadly uncommon and native wild crab apple, Malus sylvestris, which grows amongst hedgerows and wood. The majority of crab apples grown today are in fact derived from other species. Crab apple trees tend to produce small to medium size fruits, which are often yellow, orange or red in colour depending on the variety. The fruits can be rather unpalatable and tart when eaten raw, but they are perfect for making delicious jams, jellies and sauces.1 Most crab apple trees produce a wonderful, often scented blossom, with either pink or white flowers, which not only look stunning and signal the arrival of spring, but are loved by pollinators as well. Crab apple trees are self-fertile and are sometimes planted near other apple trees or in orchards, as crab apples can pollinate other apples depending on their pollination group. Long associated with love and fertility, crab apples are rich in symbolism and are sometimes known as ‘jewels of the countryside’, especially during winter when their fruits hang like gems amongst the bare branches.2 When used for burning they are often prized, as the wood gives off a sweet scent when burned. “Planting a young crab apple tree bare root in winter will be inexpensive and give you instant blossom the following spring and decorative fruits in the autumn,” shares Garden Designer Non Morris. Crab Apple Varieties There are many different crab apple tree varieties that grow well here in the UK and can be found in various forms from half standards and weeping varieties to columnar habits. With pale or dark blossoms, large or small fruits, for culinary purposes or purely ornamental, the choice is endless. However, here are some of the most widely available varieties here in the UK. Malus ‘John Downie’ ‘John Downie’ is a widely grown variety which will grow to an eventual 6m in height and 4m in spread over time. It produces beautiful white flowers in spring and large orange fruits, perfect for making preserves. Malus × atrosanguinea ‘Gorgeous’ This ‘Gorgeous’ variety produces a lovely white blossom in spring and a heavy crop of red fruits, which stay on the tree right into winter and give some lovely winter interest to the garden. Grows to an eventual height of 5m and spread about 4m wide. “One of my favourite varieties is ‘Gorgeous’, which has large, glossy, bright, red fruits which remain on the tree until Christmas,” says Non. Malus ‘Evereste’ This variety can grow to up to 6m tall and 5m wide over time. With its larger-than-average white flowers in spring, stunning fruit and more conical form, it is a great specimen to behold. Having been awarded the RHS Award of Garden Merit (AGM) it has been shown to perform reliably well.3 Malus ‘Comtesse de Paris’ ‘Comtesse de Paris’ is a small tree growing to only 4m tall and 3m wide over time. It displays a stunning white blossom following pink-tinged buds in spring and yellow fruits into the autumn. Similar to Malus ‘Golden Hornet’, although with better disease resistance.4 Malus ‘Wisley Crab’ This variety is slightly different. With its purple blossom in spring, it produces large and dark red fruits into autumn, which are great for making jellies. When mature it can reach heights of up to 5m and a 4m spread. How To Grow & Care For Crab Apples Crab apples tend to grow best in loamy soils, but will grow well in any moist, well-drained and fertile soil. They are not a fussy tree to grow, but do dislike waterlogged ground, so it is best to grow them in free draining soil. Crab apples can be grown in either full sun or partial shade and will cope with either a sheltered or exposed site. However, they will certainly benefit with some shelter from the winds to protect the blossom and encourage pollination. Crab apple trees can be bought either as potted throughout the year or as bare root from November until March. Bare root trees should be planted quickly on arrival. However, if this is not possible due to the ground being frozen or covered in snow, the tree can be stored somewhere cool with its roots wrapped in polythene (if purchased as a bare root tree) to stop them from drying out. Planting To plant a crab apple tree, dig a square hole twice as wide as the root ball or roots and at least as deep, loosening the soil at the sides and bottom of the hole. Place a tree stake near to where the main stem will be and lower the tree into the hole to the same depth as it was previously planted. Backfill with soil, gently firming the soil in around the roots to avoid any air pockets. Water in well, attach the tree to the stake with a rubber tie and lay an organic mulch around the tree, which will help suppress weeds and conserve moisture. Water well for the first few years, especially during hot and dry spells, until established, as Master Horticulturist Roy Nicol shares: “A lack of watering is the most common reason for a tree to fail. “Either tree irrigation bags or tree irrigation kits, where a plastic tube down to the tree’s roots is installed when planting, can be used to ensure a plentiful supply of water for the growing tree.” Pruning Crab apples belong to pruning group one and require formative pruning to encourage a good open shape to allow light and air in. Most newly purchased trees will come with formative pruning instructions to follow, but guidance can be found online if required. Once established, crab apple trees are similar to other apple trees and require annual pruning to remove any dead, diseased and crossing branches. Common Problems Scab Crab apples are susceptible to a fungal disease called scab or Venturia inaequalis. Scab spores are airborne and can even survive the winter, harbouring in fallen leaves. Symptoms of scab often include brown scabby spots on the fruit, cracking on branches and twigs and green blotches on the foliage, which gradually become darker and often lead to the leaves falling prematurely. No chemical control is currently available for the home grower, so if scab is present swift action is recommended. Cracked or blistered wood and fallen, infected leaves and fruit need to be removed in order to reduce the amount of fungus around for the following growing season. Apple Canker Canker is another fungal disease, Neonectria ditissima, that can affect apples, pears and some other species. Apple canker affects the bark and wood of the tree, leading to the bark dying and eventual dead branches. “Although certain varieties are more susceptible to canker than others, canker normally enters the tree via a wound of some kind, so care should be taken to avoid damaging the bark of the tree, which is easily done when pruning,” shares Roy. Cankers tend to appear in spring with the bark dying and eventually falling off, leaving the dead wood of the inner tree exposed and leading to the wood above the canker dying. There is sadly no chemical control for canker. If canker is spotted, the advice is to cut off any affected smaller branches or twigs and cut the canker out of larger branches removing all diseased bark and wood. “It’s very important to sterilise tools after this as the fungal infection can be carried to the next tree being pruned,” adds Roy. The wounds can then be painted with a wound-healing paint that will hopefully prohibit any reinfection to the wound. Fireblight Fireblight was first discovered in the UK in the 1950s and is a bacterial disease that looks as though the leaves and twigs have been scorched, hence its name.5 Fireblight usually affects apple, pear and other ornamental trees in the Rosaceae family from spring through until autumn. Caused by the Erwinia amylovora bacteria, symptoms can include scorched-looking shoots, cankers appearing and flowers dying at the time when they should be in bloom. As with canker, there is no chemical control available. Instead, if fireblight is spotted it is recommended to act swiftly, as fireblight spreads rapidly and to cut off any infected material and some way back into healthy wood. Again, it is important to not compost any affected prunings and disinfect any tools used. References 1. Crab apple. (2022, May 30). BBC Good Food. Retrieved March 14, 2023, from https://www.bbcgoodfood.com/glossary/crab-apple-glossary 2. Crab Apple (Malus sylvestris). (n.d.). Woodland Trust. Retrieved March 14, 2023, from https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/british-trees/a-z-of-british-trees/crab-apple/ 3. See RHS lists of top AGM garden-worthy plants, fruit & veg. (n.d.). Royal Horticultural Society. Retrieved May 15, 2023, from https://www.rhs.org.uk/plants/trials-awards/award-of-garden-merit/agm-lists 4. Malus “Golden Hornet.” (n.d.). Royal Horticultural Society. Retrieved March 14, 2023, from https://www.rhs.org.uk/plants/98350/malus-golden-hornet/details 5. Erwinia amylovora (fireblight). (2022, January 7). CABI Compendium. https://doi.org/10.1079/cabicompendium.21908
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How To Plant And Grow An Olive Tree, In Collaboration With Paul And Antonia Smith
IN THIS GUIDE Overview Olive Varieties Planting Olive Trees Olive Tree Care Propagation Harvesting & Storage References Olive trees can instantly add a Mediterranean feel to any garden aesthetic. Despite their roots in warmer climes, they tolerate the British weather remarkably well – provided they’re given pride of place in terms of sun and shelter. In this guide, we’ve collaborated with The Norfolk Olive Tree Company, which is run by Paul and Antonia Smith. “The Olive Tree provides yearlong colour and interest and produce flowers in spring that are beneficial to wildlife – the bees love them,” says Paul. “It is a small, slow-growing tree so it is ideal for small gardens and border displays”. Although they’re less likely to produce a plentiful harvest in the UK, it is possible to coax a small yield from these slender and stylish trees – just don’t expect to be pressing your own olive oil any time soon. In any case, even if you don’t manage to get your olive tree to actually produce olives, it’ll still be an elegant addition to any garden display. With silvery, leather-like foliage and compact, upright architecture, smaller varieties are ideal for locations where space is at a premium. Overview Botanical Name Olea europaea Common Name(s) Olive Tree Plant Type Evergreen Tree Native Area Mediterranean Hardiness Rating H4 Foliage Bushy evergreen foliage with leathery leaves growing on opposite sides of the branch Flowers Small white panicles When To Plant March, April, May, June, July, August, September Flowering Months May, June, July, August When To Prune April, May Did you know that olive trees are capable of surviving for millennia? In fact, the oldest known specimens of this Mediterranean stalwart are believed to be between 2,000 and 3,000 years old.1 It’s little surprise, then, that they were favoured by the empires of both Ancient Greece and Ancient Rome.2 It’s for that reason that they’re virtually synonymous with the sultry climes and laid-back lifestyle of a holiday overseas, and planting one in your garden can replicate that inviting atmosphere. Though they are demanding in terms of the sunlight and shelter they receive and the drainage of their soil, they’re largely resilient plants which don’t require too much in the way of TLC otherwise. That, and their aptitude for container cultivation, make them an increasingly common sight in sunny spots around the UK. Olive Varieties There aren’t massive discrepancies in the growing habits and maintenance requirements of different olive tree cultivars, but there are certain varieties which can fruit more reliably or tolerate cold more effectively than others.3 As such, it’s a good idea to tailor your selection to your particular regional climate and the purposes for which you want the tree in the first place. “If you’re planning to grow fruit, we recommend the Arbequina” explains Paul Smith. “Otherwise, we favour the Leccino Olive Tree, which can grow up to 30 feet. “However, they are not self-fertile and will need a pollinator to grow fruit”. Paul and Antonia also express a fondness for the Picual Olive Tree, as they are good for overwintering in the UK and are particularly resistant to pests and diseases. Here’s a little more info on the more common varieties found in the UK: Olea europaea ‘Arbequina’ This Catalan variety hails from the east of Spain and is particularly suited to areas prone to frost or poor soil quality. It’s on the smaller side, growing up to 6m, but can be quite vigorous in its development. O. europaea ‘Frantoio’ This classic specimen is native of Tuscany in central Italy and is perhaps the number one choice for those looking to reap a decent fruit harvest from their tree. It’s very easy to cultivate in the UK, too. O. europaea ‘Pendolino’ With compact dimensions and a weeping structure, this Tuscan alternative is excellent for smaller spaces. However, it will need to be planted alongside other olive varieties in order to have any chance of producing fruit. Planting Olive Trees When planting an olive tree in the ground, dig a hole twice the width of the root ball and enhance the quality of the soil with mycorrhizal fungi or another organic aid, which will facilitate rapid root establishment. Spread the roots out when planting and tamp down the soil. Drainage is key, regardless of how you plant your olive tree, as Paul explains: “Olive trees are not fussy about soil type, but it must be free draining. “So, if you have clay soil break it up with grit and sand and test it before planting, making sure that water will drain”. It’s also advisable to stake plants for the first several seasons to allow their roots and trunk to develop. Where To Plant Olive trees love sunlight, so choose the sunniest and most sheltered spot in your garden.4 “I recommend growing an olive in a pot against a sheltered sunny brick wall for the best chance of ripened olives,” says Master Horticulturist Dan Ori. Olive Tree Care Olive trees are famously drought resistant – but that doesn’t mean they will thrive without regular watering and feeding. Here’s a rundown of their main demands: Preferred Sunlight & Temperature Ideally, olive trees prefer the warm climes of their native Mediterranean. However, several cultivars are more tolerant of cold than others. Generally speaking, they’ll do best when summer temperatures reach 20°C or more, while in winter, they can survive anything as low as -10°C for a short period of time. In terms of sunlight, more is invariably better. That’s why it’s important to position your olive tree in a position where it is likely to receive as much exposure to the sun’s rays as possible. Watering Though olive trees will survive periods of drought, their flowering and fruiting habits will definitely be negatively impacted without water. For that reason, it’s advisable to keep them well irrigated. Younger trees are more susceptible to becoming parched, but even mature varieties will feel the impacts in excessively long dry periods. The former will require occasional watering in winter, while the latter does not demand any during the colder months. Having said that, no olive tree withstands waterlogged roots for any stretch of time. That’s why it’s imperative that the soil the tree is planted in enjoys good drainage, regardless of whether it’s a pot or the ground. Feeding Use liquid fertiliser once a month from mid-spring until late summer to encourage maximum growth and an optimal yield of olives. During this time period, the best results will be witnessed when feeding lightly but regularly. In early spring, you can set it up for the growing season ahead with bonemeal, blood and fish feed, while mulching it with plenty of organic matter once every two years is advisable for a healthy, happy tree. For potted specimens, Paul Smith recommends a regular feed from March to October and notes that any feed that is seaweed based, such as tomato fertilisers, are the best choice. Common Problems & Pests Generally speaking, olive trees don’t suffer too badly from diseases or blights. However, if your tree is allowed to become excessively wet, it may be susceptible to phytophthora root and verticillium wilt.5 Honey fungus and olive scab are other occasional problems to watch out for. In terms of pests, the humble mealybug is chief among your worries. They can suck the sap out of the branches and secrete honeydew onto leaves, causing them to turn black with mould. Deal with them using an organic pesticide where applicable. Winter Protection Trees grown in the ground should be protected with horticultural fleece or hessian in parts of the country susceptible to extreme cold during winter. Spreading a layer of mulch over the root systems is a good way to insulate them from the cold as well. For potted varieties, moving them to an unheated conservatory or greenhouse will suffice to keep them safe during winter. If that’s not an option, use fleece or bubble wrap to insulate the container and protect the roots. “Olives will easily tolerate our UK winter temperatures and they will fruit better if exposed to a few cold months,” says Dan. “What they don’t like is cold and wet or exposed sites, so if you have soil that becomes waterlogged in the winter I recommend growing in a pot. “Wrapping your olive in horticultural fleece can be beneficial during the first and late frosts. If you are concerned about it surviving the winter where you are you can move it into an unheated conservatory or greenhouse.” Propagation It’s possible to propagate olive trees and achieve a relative degree of accuracy between the parent tree and the offshoot. Do so by taking semi-ripe cuttings (young branches less than one-year-old) in summer or hardwood cuttings in winter. Take the cutting just below a leaf node and strip all leaves from near the base, leaving at least four near its tip to retain moisture. Dip the base in rooting hormone, then plant it firmly in the rooting mixture and tamp down the compost around it. Both the soil and the cutting will need to be kept warm (around 20°C) and moist for the first few months after planting. After the roots have established, it can be transplanted outside or into a pot. Harvesting & Storage Olive trees begin producing fruit when three to five years old and should be harvested in autumn. Those favouring green olives should strip them from the tree when they reach full ripeness, though they must be soaked in salt water for a few days to make them tasty. On the other hand, if you prefer black olives, allow them to remain on the plant until they firm up and darken in colour. Once black, remove them from the tree and dry-cure them in salt for a few weeks to dehydrate them. Regardless of which type of olive you harvest, they should be stored in either brine or olive oil to retain their freshness for as long as possible.6 References 1. Raezer, D. (2022, October 11). World’s Oldest Olive Tree. Approach Guides. Retrieved March 21, 2023, from https://approachguides.com/blog/oldest-monumental-olive-tree-vouves-crete/ 2. Cartwright, M. (2016, September 9). The Olive in the Ancient Mediterranean. World History Encyclopedia. Retrieved March 21, 2023, from https://www.worldhistory.org/article/947/the-olive-in-the-ancient-mediterranean/ 3. Olea europaea (F) | common olive. (n.d.). Royal Horticultural Society. Retrieved March 21, 2023, from https://www.rhs.org.uk/plants/11735/olea-europaea-(f)/details 4. Koubouris, G., Kavroulakis, N., Metzidakis, I., & Sofo, A. (2015, March). Ultraviolet-B radiation or heat cause changes in photosynthesis, antioxidant enzyme activities and pollen. . . ResearchGate. Retrieved March 21, 2023, from https://www.researchgate.net/publication/273696243_Ultraviolet-B_radiation_or_heat_cause_changes_in_photosynthesis_antioxidant_enzyme_activities_and_pollen_performance_in_olive_tree 5. Verticillium wilt. (n.d.). Royal Horticultural Society. Retrieved March 21, 2023, from https://www.rhs.org.uk/disease/verticillium-wilt 6. Demaio, P. (2021, February 26). It’s a keeper: how to preserve your own olives at home. The Guardian. Retrieved March 21, 2023, from https://www.theguardian.com/food/2021/feb/27/its-a-keeper-how-to-preserve-your-own-olives-at-home
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These 6 Laburnum Types Are Commonly Grown (With Only One Given AGM Status)
IN THIS GUIDE 1) L. alpinum 2) L. anagyroides 3) L. alpinum ‘Pendulum’ 4) L. anagyroides ‘Sunspire’ 5) L. watereri 6) L. × watereri ‘Vossii’ Other ‘Laburnums’ References Laburnums are native to a belt of Western and Southern Europe from France and Germany through Italy and Greece to Romania, and spanning the Alps and the Balkans.1 It arrived in the United Kingdom in 1560 and quickly established itself as a desirable ornamental tree.2 Genus Laburnum is a member of Family Fabaceae – the Pea Family or Legume Family.3 It has only three confirmed species: L. alpinum, L. anagyroides, and a common hybrid L. x watereri. The last-named arose from a hybrid; however, nearly all Botanical and Dendrological authorities, including Kew and World Flora Online, name it as an accepted species.4 Also named within the genus are nearly 50 unresolved and little-known species plus several hybrids and cultivars nearly all of which have come and gone with the seasons. Both L. alpinum and L. anagyroides when grown as trees attain heights from 4-8m, reaching ultimate heights after about 20 years. Their spreads too are from 4-8m. 1) L. alpinum L. alpinum is also called ‘Scotch laburnum’ or ‘Scottish laburnum’ but not because it is ’Scottish’! Apparently the Scots appropriated the tree and somehow named it because they valued – and continue to value – its wood, and particularly its heartwood, for – among other uses – making bagpipes. 2) L. anagyroides Laburnum anagyroides Racemes In contrast, poor L. anagyroides is only called ‘Common laburnum’! Both species bloom in late May and the beginning of June. L. alpinum racemes, at 35-40cm, are very long compared to those of L. anagyroides which are 15-20cm. On the other hand, L. anagyroides racemes are denser and thicker. Another point of difference is the foliage. L. alpinum’s leaves are a crisp dark green whereas those of L. anagyroides are a dull greyish-green. The former’s leaves are glabrous or smooth while the latter’s have fine downy hair on the underside. Among the numerous cultivars that have come and gone, one stands out for each of the species. 3) L. alpinum ‘Pendulum’ So named because its branches are pendulous, which enhances the ‘dangling gold chain’ effect when the tree is in bloom and the ‘weeping’ boughs move in the wind. Another reason it stands out is that it is a dwarf variety reaching an ultimate height and spread, both, of only 1.5-2.5m. 4) L. anagyroides ‘Sunspire’ Also a dwarf but it has a narrower, fastigiate form, attaining an ultimate height of 2.5m with a spread of (only) 1m. Like its parent, the racemes are short but dense. Upon emerging the racemes are erect and stay erect for about a fortnight. 5) L. watereri Hybrids arose naturally from the two ‘main’ species, including in the UK, and they are collectively called L. watereri. 6) L. × watereri ‘Vossii’ However, the most desirable and most well-known Laburnum is a cultivar, L. × watereri ‘Vossii’. It is the only Laburnum variety to have received the RHS’s Award of Garden Merit. “It is popular for a reason and its AGM status proves the point,” adds Colin Skelly, a Master Horticulturist. “I have planted the species in gardens where species have been preferred, but the vigour and floral impact of ‘Vossii’ means that this is the choice selection for most gardens.” A ‘watereri’ hybrid that occurred in the wild in the Tyrolean region was found in the 1850s and brought to the Netherlands where ‘Vossii’ was cultivated from it in the late 1800s. Like its parent species, it attains an ultimate height and spread of 4-8m. Overall, ‘Vossi’ exhibits a few characteristics of each parent. Consider: both the young stems and leaflets are initially pubescent but become glabrous as they mature. In general, ‘Vossii’ brings together the best attributes of each parent and introduces a couple of new ones. It produces far fewer seed pods, each of which has fewer seeds. Bodnant Garden in Wales Even the foliage is a more appealing shade of green, being less grey and less dark. As for the racemes, they are spectacular: the flowers’ hue is a rich golden yellow, they are dense and lush, and they are 50-60cm long. The spectacle lasts from two to three weeks. L. × watereri ‘Vossii’ is the most popular Laburnum variety in the UK and in other countries as well. Other ‘Laburnums’ Giving some competition to the Laburnum is another ‘Laburnum’ – the ‘Indian Laburnum’, or Cassia fistula which is, obviously, a species of a different genus, Cassia. Laburnum and Cassia trees do look quite similar in the flowering season when Cassia trees are also covered by a profusion of drooping, thick racemes of small, bright yellow flowers. In fact, Cassia too is a member of the Family Fabaceae.5 Cassia trees are of considerable cultural significance in Thailand, Laos, Sri Lanka, and India. Besides Tropical East Asia, their native range spans the Equatorial and Tropical regions of Africa and South America.6 Evidently, these trees’ climate preferences are very dissimilar to the ones it is physically so similar to. Among the many species, a good few are native to even some of the hottest regions of the planet. For instance, Cassia sieberiana grows in Western Africa from Mauritania and Liberia to Nigeria. Then there is a ‘Nepal laburnum’ – Piptanthus nepalensis, with the genus (Piptanthus) also being a member of the Fabaceae family. This Himalayan native also puts on wonderful summer shows but its yellow-flowered racemes are only 4cm short. However, it too is quite popular in European countries because, though its racemes’ length is a small fraction of those of even Laburnum anagyroides, what to speak of ‘Vossi’, unlike Genus Laburnum’s species, Piptanthus nepalensis is tough, pest-resistant and disease-free, and, therefore, low care. Finally, we have “Adam’s laburnum”, with the botanical name Laburnocytisus ‘Adamii’. This wonderful curiosity is a hybrid of Laburnum and Purple Broom with the result that in the spring flowering season, some branches are thick with yellow Laburnum racemes while other branches bear Purple Broom flowers! References 1. Laburnum anagyroides. (n.d.). Missouri Botanical Gardens. Retrieved March 20, 2023, from https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=280634 2. Common laburnum. (n.d.). The Wildlife Trusts. Retrieved March 20, 2023, from https://www.wildlifetrusts.org/wildlife-explorer/trees-and-shrubs/common-laburnum 3. Laburnum. (n.d.). Kew Royal Botanic Gardens. Retrieved March 20, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:22728-1 4. Laburnum × watereri. (n.d.). Kew Royal Botanic Gardens. Retrieved March 20, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:501463-1 5. Fabaceae. (n.d.). Science Direct; Elsevier BV. https://doi.org/10.1016/b978-0-12-405927-6.00016-3 6. Cassia bakeriana. (n.d.). Kew Royal Botanic Gardens. Retrieved March 20, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:484178-1
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These Noteworthy Almond Tree Types Produce Lovely Blossom And A Robust Harvest
IN THIS GUIDE 1) Prunus dulcis 2) P. dulcis ‘Macrocarpa’ 3) P. dulcis ‘Ingrid’ 4) P. dulcis ‘Robijn’ 5) P. dulcis ‘Princess’ 6) P. dulcis ‘All-In-One’ 7) P. dulcis ‘Nonpareil’ 8) P. dulcis ‘Carmel’ 9) P. dulcis ‘Texas Mission’ 10) P. dulcis ‘Marcona’ 11) P. dulcis ‘Valencia’ 12) P. dulcis ‘Pizzuta’ 13) P. dulcis ‘Mamra’ References Almond trees come in quite an array of varieties. There are California’s high-yield commercial cultivars, and there are the ‘connoisseur varieties’ of Southern Italy, Spain, and Iran that are the pride and joy of growers of those respective countries. Not to forget the ‘no-yield’ dwarf flowering ornamental trees. Underneath we present the varieties that we recommend for British home gardeners. 1) Prunus dulcis The ‘mother ship’ and unlike many cultivars, it is fairly drought-tolerant. “Unless you really are out to optimise your almond harvest, the drought tolerance of the species would provide you with flowers, harvest and resilience in a changing climate,” adds Colin Skelly. Its fruit is ready for harvest around September. Though it can be grown in British home gardens, better options are available. 2) P. dulcis ‘Macrocarpa’ A good choice for British gardens. It is early to blossom in early spring, producing pale pink and white flowers, and also produces an early harvest in August. The almond is quite sweet. 3) P. dulcis ‘Ingrid’ This is a popular cultivar that is gaining ground in England because of its lovely pink blossoms in spring and the rich buttery taste of the almond. Be warned that it is very hard-shelled; on the other hand, this is a self-pollinating variety. 4) P. dulcis ‘Robijn’ Another top choice. For one thing, this one is soft-shelled and for another, the almond has a remarkably sweet flavour. Its blossoms are especially delightful. This too is a self-pollinating variety. 5) P. dulcis ‘Princess’ Rounds up the European self-pollinating varieties. One can consider this a ‘connoisseur almond’ for the amateur gardener because the shells are soft and the almond is unusually sweet and scented, ready to eat off the tree. 6) P. dulcis ‘All-In-One’ An American self-pollinating variety that grows to only about 4m. The fruit is both soft-shelled and sweet. It blossoms late and correspondingly yields a late harvest from the end of September to early October. From the many dozens of other almond varieties, here are some of the most noteworthy – 7) P. dulcis ‘Nonpareil’ Those famed California almonds that are available around the world are from the ‘Nonpareil’ tree which is the world’s most abundant cultivar. The almonds are valued for their smoothness and good taste. It bears high-yielding drupes as the almond content (as opposed to shell) is from 60-65%.1 8) P. dulcis ‘Carmel’ ‘Carmel’ is a more recent California cultivar. The almond is smaller and rounder. They are usually blanched or roasted for munching on ‘out of the bag’. 9) P. dulcis ‘Texas Mission’ ‘Texas Mission’ is not only a high-yield tree, it is one of the few commercial varieties that can relatively easily be grown in the garden. It produces a sweetish almond. 10) P. dulcis ‘Marcona’ The ‘Marcona’ produces an almond that is short and plump in appearance. The nut is soft and has a distinctly sweetish flavour. From Spain, it is considered a connoisseur almond. 11) P. dulcis ‘Valencia’ ‘Valencia’ almonds are more oblong and flattish. Also from Spain, these are not soft like the Marcona and have a more robust flavour. 12) P. dulcis ‘Pizzuta’ ‘Pizzuta’ from Avola, Italy, is identified by the reddish-brown nut. A sweetish almond that is considered a fine variety, it is often used for making confectionery. 13) P. dulcis ‘Mamra’ Though several kinds of almonds are grown in Iran, ‘Mamra’ is the country’s top variety. It is distinguished by the soft shell and the nut’s wrinkly, curved form. A sweet almond, it is ideal for confectionery. References 1. New approaches For Almond Production In Mediterranean Climates: A Review. (n.d.). eScientific. Retrieved March 9, 2023, from https://escientificpublishers.com/new-approaches-for-almonds-prunus-amygdalus-batsch-production-in-mediterranean-climates-a-review-JAA-05-0055
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The Signs To Know When Your Plums Are Ready To Harvest (And How To Protect Them)
IN THIS GUIDE 1) Protect Your Incipient Harvest 2) Thin The Crop 3) Test For Readiness 4) Pick The Fruit Plums may well be the sweetest, juiciest, most luscious of fruits to bite into and delight in. Unfortunately, many people would not agree with that assessment – and the reason is that all they’ve ever eaten are mass-produced store-bought plums that have been transported over long distances! But if you have a plum tree or two in your front yard, you may well agree with our opinion. And you’ll agree with it even more if you harvest your plums correctly and methodically. As a plum grower, you know that colour is one indicator of ripeness and harvest-readiness. And you would also know that plum varieties’ colours vary – red, maroon, burgundy, purple, and even green. However, there are other indicators of harvest-readiness as well as a few do’s and don’ts. Difficulty Medium Equipment Required Gardening gloves, mini-secateurs or scissors; a helper may be useful When To Harvest July – September Underneath we take you through the ins and outs of plum harvesting so that you may reap the most ‘fruitful’ harvest: Protect your incipient harvest from frosts and birds Thin out branches for a healthy crop Test your plums for readiness Pick the fruit when it’s ready This process is explained in more depth below – 1) Protect Your Incipient Harvest Plums are susceptible to two threats: early frosts when the blossoms are on show and birds when the fruits are forming. (These are the two most common and major threats to plums but are far from the only ones.) So you need to take care of your harvest right from spring when it is not even formed. If you anticipate a late spring frost you will need to keep buds and flowers snug with fleece or similar protection lest they get zapped. As for birds, mesh netting is difficult to set up and ugly to look at but it is a very effective method to frustrate birds; other methods are also available. Increase the amount of water during the height of summer when the fruit is developing and maturing. Increasing the amount of water is critical during hot, dry spells. Wear gardening gloves when it’s your turn to thin the fruit after Mother Nature has taken her turn. 2) Thin The Crop Plum trees are very generous – indeed, they’re generous to a fault. They crop so heavily that they cannot possibly bring all the fruit to ripeness, and overburdened branches sometimes even break. This fault is partially compensated for by Mother Nature and should be partially compensated by you. Mother Nature does her part through ‘June Drop’ when some number of immature plums fall off the tree. This fruit fall is normal. Actually, this June Drop is a marvellous signal for you to play your part. Immediately after this automatic thinning is over, you should thin the forming fruit, though how much depends on your cultivar and on how much your tree is overloaded. Branches should not be under obvious strain. Simply snip off a conservative number of fruits; use mini-secateurs or even scissors for this purpose. Choose under-developed, mis-shapen, and damaged fruit for thinning. “When thinning plums, I use the RHS guidance for thinning, which is to leave a plum every 5-8cm or a pair of plums every 15cm,” shares Master Horticulturist Colin Skelly. “This works well for me, leaving a crop of good-sized plums that are plentiful but without overloading the branches.” Though plums can be ripened after picking, they taste best when tree-ripened. Therefore, it is important to pick these fruits at just the right stage. 3) Test For Readiness Depending on your cultivar, plums will be ready to be picked sometime between July and September. All plums on a tree will not ripen at the same time. Your harvesting will consist of several go-throughs, at each of which you would pick some fruit – a little or a lot. But when do you know that the fruit is tree-ripened and should be picked? Here’s a checklist:– No matter what the colour of your cultivar’s plums, except for a few marginal plum types like cherry plums, ready-to-pick ripe plums will have a chalky glaze. While unripe plums will be very firm, ripe plums will have a bit of ‘give’ or some softness if gently squeezed between finger and thumb. Ripe plums exude a mild sweetish scent that unripe plums usually don’t. Ready-to-pick plums will come away fairly easily from the branch; all they need is a gentle pull using only finger strength with a bend or twist, with only a touch of support, if any, to the branch. If the branch moves to more than a very small degree when you pull a plum, the plum is not ripe. Pick a plum that you think is ripe, wash it if necessary, and bite into it. You’ll know for sure if other plums like it are ready or not! 4) Pick The Fruit Support the branch – you may have to hold back on a cluster of plums – with one hand while you pick a plum with the other. However, there is an acquired technique to picking fruit like plums with a single hand (and you’ll be glad if you acquire this technique if you haven’t already done so). Hold up or push back the branch (or cluster) with your thumb while plucking with two fingers pressed against the palm, using a quick bend or twist. No matter how you detach a plum, if one or more other plums in that cluster are well-ripened or have a weak stem then the resultant recoil or jarring may result in such fruits falling to the ground! If the ground is muddy, those fruits will get dirty; if it is hard, they’ll get bruised. To guard against this you may want to hold a basket underneath the plum you are picking; even better if you have a helper to hold the basket. Remember you won’t harvest your entire crop in one go; only those plums that are ready. You’ll need to make a few passes during the harvesting season to collect your full harvest.
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