Trees to help Wildlife
Trees and shrubs give structure and beauty to a garden and provide wildlife with food, shelter and nesting sites. Most gardens have a space for a least one tree and even a patio can have wildlife friendly shrubs or a small tree.
Evergreen trees give year round foliage and deciduous trees give variety in shape, leaf, colour, flowers, fruit and seeds.
A few we recommend.
Birch – Betula The beautiful Silver Birch – Betula pendula and Downy Birch – Betula pubescens are both native varieties and have catkin flowers from early spring. The bark, young leaves and the large amount of seed attract insects which in turn attract birds that enjoy both the insects and the seeds. The great spotted woodpecker is one such bird who will be helped from the presence of these trees.
Holly – ilex aquifolium There are many species of Hollies, with prickly, spiny or smooth-edged leaves. Generally always evergreen, hollies are a great source of food for birds such as robins, sparrows, black birds and many others. The holly provides food for blue butterflies in spring. Often a lifeline in the winter months, hollies also provide shelter and protection for wildlife and can also provide a protective hedge to keep out intruders.
Rowan – Sorbus aucuparia The Sorbus has many species of deciduous trees and shrubs, with some varieties being suitable for small gardens. Mistle thrush, blackbirds and starlings eat the wonderful red berries and the chicks feed on the aphids and sawflies that live amongst the branches of the Rowan tree. Rowan leaves are ornate and either pinnate or lobed. Some varieties such as whitebeam have dark upper sides and pale grey-green undersides to their leaves which are rather pretty.
Ivy – Hedera helix Evergreen Ivy leaves comes in three shapes, the usual three-lobed type, a five-pointed or crested leaf and a rounded leaf. The Ivy, when mature flowers from October onwards, providing nectar as late as December before producing dark purple fruit on which song thrush and blackbirds feed. Walls or hedges with mature ivy provides nesting sites for our fragile little wren and even blackbirds, as well as a host of hibernating creatures including butterflies. Ivy is an often overlooked asset for our garden birds.
Monthly Tips and general advice
You are still able to plant bareroot trees and hedgerow, and it is advisable to put tree guards so that rabbits can not knaw the bark off.
Pruning of many deciduous trees, shrubs and hedges is easier to do from now and throughout when they are dormant. This is so that you can see what you are doing, however evergreens and tender plants should be left till spring.
Patio and Conservatory ideas
With so many people having patio and conservatories, small trees and shrubs become more important in the area immediately around your home. Shape, fragrance and colour offer year round pleasure and minimal maintenance is helpful for those who have a busy life style or are retired.
We suggest trees and shrubs such as Olives, Bays and Citrus which are evergreen, together with roses, climbers and bulbs for year round interest. Vines, Figs, dwarf Apple and Cherry trees are all beautiful and useful additions to patio and conservatories.
Choosing pots involves both the setting and what you intend to grow. Terracotta is always useful as it is porous and remains cool. Lightness is important with larger pots if they need to be moved for different seasons. Compost and general feeding together with watering is all important for a successful and pretty garden space.
Advice on what to do when you receieve your tree and planting
After unpacking your tree, please give it a good soak in its pot.
Prepare hole, this should be approx twice the width of the pot and one and half times the depth. The tree would like a little Bone Meal so sprinkle some in the hole. (This can be bought from any Garden Centre and most hardware shops)
Lift tree out of pot, keeping as much soil intact around the tree. DO NOT TOUCH THE ROOTS. Place tree in the prepared hole. Fill round the roots and bottom of trunk with soil.
Press soil round trunk firmly. Mulch if you want. Stake tree if necessary and WATER THROUGHLY. If you have rabbits or other such animals, put a tree guard around the lower end of the tree.
If you are planting the tree in a dry period, do take time to water so that the tree does not dry out but be careful not to overwater.
If you are planting in a very cold spell, often spreading straw, hay, sacking or even old newspaper can protect the base of the tree from a cold frost.
Planting pruning and moving
In colder northern regions, and early in the month, you can still move and plant evergreen trees and shrubs, provided the soil is not waterlogged. They are best moved or planted once actively growing and when there is less risk of cold. In warmer regions, it is best to wait until the autumn, as the weather will soon turn warm and dry, and the plants will have trouble establishing.
In colder areas, you can also still plant container-grown deciduous hedging plants, shrubs, trees and climbers. Stakes and rabbit guards should be put in place at the time of planting to prevent damage to the rootball and bark. Remember that watering and establishment may be problematic as the weather gets warmer and dryer, and you may be better planting in October.
Twining climbers (such as honeysuckle and Clematis) need regular tying in and twining around their supports.
Young mimosa trees (Acacia dealbata) can also be cut back now. Mature trees respond less well to pruning.
Make sure that as the weather gets warmer all newly planted trees and shrubs are not allowed to dry out, and water with rain or recycled water where possible
Feeding and mulching
Mulch rose and shrub beds with a 5-7.5cm (2-3in) layer of organic matter. This will help retain moisture during dry spells, reduce weed build-up and over time improve soil structure. Pay particular attention to mulching around rhododendrons, azaleas and camellias as flowering is impaired if they are allowed to dry out during late summer.
Feed trees, shrubs and hedges with a balanced fertiliser (such as Growmore or blood, fish and bone), sprinkling it over the root area before hoeing into the soil surface. This will particularly benefit young, weak, damaged or heavily pruned plants.
Pruning and training
If not completed last month or before, winter-stemmed shrubs such as Salix and Cornus can still be cut back at the beginning of the month. Prune back hard all the previous year’s growth to within 1-2cm (0.5-0.75in) of the framework.
Other shrubs that are routinely stooled (cut back hard) in spring, to keep their larger or more brightly coloured juvenile foliage (such as Cotinus and Sambucus), can be cut back this month. You can leave a couple of branches un-pruned if you are reluctant to lose all the height gained last year.
Delay pruning spring-flowering shrubs such as Forsythia and Chaenomeles until after they have finished flowering, otherwise this year’s display will be lost.
Remove any frost damaged shoots from evergreens damaged by earlier cold weather.
Remove any reverted green shoots on hardy variegated evergreens, to prevent reversion taking over.
Notes in the Care of Citrus
Citrus trees make interesting and attractive indoor plants. They provide year-round interest, with fragrant white flowers, followed by small fruits which take 4-6 months to reach full size. The fruits can be picked at any time after ripening, and will retain their flavour on the tree for several months. The miniature-fruited Calamondin tree makes an excellent houseplant for a windowsill; while the larger-fruited varieties are ideal for conservatories and greenhouses. Please note that citrus can be kept outdoors during the summer months
Light: All Citrus enjoy high light levels, so smaller plants will do well on a windowsill in the house. Larger plants need a conservatory, greenhouse or sheltered summer garden, but should be given supplementary light if they are to be kept away from windows indoors. Be careful not to allow leaf scorch in direct summer sun through glass. East or West facing windows are best in summer. Try to keep dark-coloured pots shaded as roots can become overheated and die; water evaporation through unglazed terracotta pots will have a slightly cooling effect.
When there is no danger of frost, Citrus trees like to be outside in the summer months. However they must be acclimatised gradually to the new light level, by being moved first to a slightly shaded area outside for 2-3 weeks before being put in their sheltered, sunny spot for the summer. Equally when being brought indoors in winter, they should be kept in the shade for 2-3 weeks before coming inside. This reduces any stress to the leaves that the sudden light change could cause.
Heat: C for short periods). They must not be frosted, but a cool period is useful over the winter to rest. They are tolerant of high temperatures, but prefer to be at neither extreme for too long. One is often unaware of just how hot conservatories can be on sunny days and of the stress this can cause to their plants and trees. A Min/Max thermometer is a ‘must’ for measuring temperatures when no-one is around. Central heating can put the trees under stress in Winter, ideally they do better in a cool room or conservatory, rather than a warm living room. (See last page for cold hardiness).°C (even 2° Most Citrus trees can tolerate temperatures down to 4
Water: Water less often in winter without letting the pot dry out completely, and increase the amount of water once growth starts in the spring. As a general rule, when the top of the compost is beginning to dry out, give enough water to reach the bottom of the pot, preferably washing a little out through the bottom each time. Do not water again until the surface of the compost starts to dry again – this may be every day in summer, but not for 2 or 3 weeks in cool winter weather. The big pots take a lot of water, so enough must be given to reach the lower part of the pot (maybe several gallons). Be flexible about watering – judge the need by the look of the compost rather than the day of the week! Over-watering can cause problems too, by drowning the roots and creating stagnant soil conditions which encourage root diseases. With small plants it may be advisable to immerse the whole pot in water to thoroughly soak the compost and allow to drain. Citrus should never sit in water for longer than about an hour.. During colder periods, compost should be kept dryer.
Feeding: Keep the top feeder roots of the tree covered with compost if possible. Trees should be fed weekly when in growth with a citrus fertiliser (high in trace elements). Use summer formulation from March to September inclusive and the winter formulation fortnightly throughout the rest of the year, or weekly if the plant is growing actively at room temperature. If citrus food is not available, then a seaweed based fertiliser is adequate if supplemented with the occasional dose of sequestrated iron and trace elements when any yellowing of the leaves occurs. Foliar feeding can also be helpful in correcting deficiencies. Too much feed will lead to scorching of the leaf tips, and it is a good idea to wash the compost through with lots of water once in Summer and again in Autumn to avoid a build up of fertiliser salts.
Humidity: The ideal humidity is about 50%. In hot weather and in central heating, humidity can drop dramatically. If the leaves show signs of stress, the humidity can be raised by a fine spray, or standing pots on a tray of wet gravel. In centrally heated conditions, a humidifier can be helpful. Increased humidity will also discourage red spider mite attack.
Flowers and Fruit: Generally flowering takes place in May, but may occur several times in the year with fruit setting each time. An enormous number of fragrant flowers appear, but only about 1% will set on the large trees (more than this would overload the branches when the fruit reaches full size). Calamondins and kumquats and some lemons, especially Meyer, set a higher percentage of fruit and may even have to be thinned to avoid weighing the branches down too much. Dry, hot conditions will not favour fruit set, which can be improved by misting the flowers.
The fruit gradually develops and turns colour around Christmas time. (The colder weather tends to act as a trigger for colouring). It will then stay on the tree for several months after ripening. Calamondins and Valencia Late Orange trees are noted particularly for holding the ripe fruit on the branches for 6-10 months.
Pollination: Most Citrus trees are self pollinating, with the exception of some Mandarines where cross-pollination with an orange improves the yield.
Leaves: Citrus trees are evergreen and will naturally drop an old leaf from time to time. If, however, there is a lot of leaf drop, then the first thing to look at is whether the tree is too dry. This is generally the cause, particularly in the lower half of a big pot. The second most common reason is poor light, so moving the tree to a lighter position may solve the problem. Over watering can also cause problems – do not give more water until the surface of the compost is looking dry. Inadequate feeding may also cause leaf drop: this can be rectified particularly effectively with special citrus food. Should the leaves drop for any reason, do not be immediately discouraged, as the tree will most likely grow a new crop of beautiful glossy leaves in a month or two, and flower soon after. Often heavy flowering and new leaf growth trigger some leaf drop in spring. This is quite normal and new leaves will fill gaps; but more diligent feeding may avoid this leaf drop in the first place.
Pruning: To keep the trees in shape, pinch out the growing tip once a new branch is 10-15cm (4-6”) long. Regular pinching out of branches will encourage bushy growth nearer the middle of the tree, and this can be carried out at any time of year. Pruning of large branches is best done in February, just before growth starts speeding up, bearing in mind that Citrus trees store excess food in their leaves, so removing too much leaf may result in a poor fruit crop.
Repotting: In general it is best to repot just before or during the growing months, rather than in the autumn or Winter. Either loam or peat-based composts can be used, mixed with extra sand or grit to improve drainage, and preferably crocks in the bottom of the pot. The ideal pH is 5-5.5, so a slightly acid (ericaceous) compost is beneficial. Loam based composts will give welcome increased stability for a tree outside, but it will also make large trees extremely heavy to move in and out of doors with the change of seasons. Where possible, pot up one size each time, with enough depth to cover the top feeder roots and give a 1” ‘reservoir’ for water. In normal conservatory conditions, where the size of tree is to be restricted, a final pot size of 45cm will be adequate. Once it has reached this size pot, instead of repotting into a larger size, take the rootball out of the pot at the end of February: if it is overcrowded with roots, cut off about 2.5-5cm (1”-2”) all around the edges, and put back into the same pot with fresh compost around the edges; or, if this has been done before with the same tree, remove 3 vertical triangles of compost from the rootball, and refill gaps. Try and roughly match the original compost, i.e. use a loam-based compost, if that has been used before. Keep the tree fairly cool and shaded for the following month, in order not to make great demand on the root system until it has started re-growing.
Varieties in order of Cold Hardiness:
- C) Citron, Lime. °Most tender (Min.6
- C) Lemon (other than Meyer), Grapefruit, Orange,Mandarine/ClementineCalamondin, Satsuma, Kumquat ‘Fukushu’°(Min. 4
- C) Kumquat ‘Nagami’, Meyer Lemon°Most cold tolerant (Min. 2
Pests: The most likely pests are aphids (greenfly), red spider mite and mealybug. These can be controlled with an appropriate off-the-shelf spray. Occasionally scale insect may settle on citrus, and can, again, be easily killed with an appropriate insecticide spray, or by dabbing with methylated spirit. As dead scale insect can harbour viable eggs under it, any scales are best removed by rubbing or scraping gently with a fingernail.
A systemic insecticide can be used to very good effect, but should be used with caution when there is any intention of eating the fruit within 2-3 weeks. (See insecticide bottle for details about use on vegetables and fruit). Sprays containing Dimethoate may cause some leaf fall in Citrus, but this is not usually too serious. Never spray a plant in full sun outside or under cover; it is best to spray either very early in the morning or in the late afternoon/evening as otherwise the leaves may become scorched.
C are necessary for most biological control agents, so they are used only between April and September, unless high levels of heat and light can be provided at other times.°Biological control insects are the easiest and cleanest methods of keeping pests down in the whole conservatory, but should not be introduced for 6 weeks after any chemical sprays have been used. In these 6 weeks, a fatty acid (insecticidal soap) spray may be used, as it is best to reduce pest populations as much as possible before bringing in any beneficial insects. Average temperatures of above 20