by Sally Morgan
Pollination
It is also important to think about pollination: fruit trees need to be pollinated, by bees and other insects, and most are self-sterile, which means that their flowers cannot be pollinated by the same tree or by another tree of the same variety. Instead, they need to be cross-pollinated by another variety of the same fruit, so you need to make sure that a suitable pollination partner is growing nearby. Cultivars are grouped according to when they come into flower during spring: Group 1 being very early, while Group 7 is very late in spring. Each group flowers for about 2 weeks, overlapping briefly with the group in front and behind. For example, a flowering Group 2 cultivar will probably come into flower in mid season, so could be pollinated by trees in Groups 1, 2 and 3.
Some cultivars are triploid, which means that their pollen is sterile, so they cannot be used to pollinate other trees, but they themselves require pollination to set fruit. Well-known triploids include some of the Bramley apples and the Blenheim Orange, Ribston Pippin and Tom Putt. Often you need two pollinating cultivars alongside the triploid – to pollinate the triploid, and to pollinate each other. But all is not lost if you only have a few trees, as pollen is carried some distance by insects, so in an area where there are lots of fruit trees cross-pollination can generally be achieved.
Check the pollination group of your chosen trees to make sure that they will all get pollinated.
Location
Think carefully about the position of your orchard within the holding. Fruit trees don’t like shade, preferring full sun, although some can tolerate partial shade, and they grow best on a free-draining soil with compost to boost the nutrient content and water-holding capacity. Avoid ground that dries out quickly in summer, floods in winter or has standing water, and don’t forget that prevailing winds can inhibit growth considerably, so the sheltered side of a wall or hedge can be ideal – but be aware that frost pockets could occur in sheltered spots.
Rootstocks
A fruit tree usually consists of two parts: the scion, which is the above-ground part, and the rootstock, which is the bit below ground. The two parts are grafted together (see page 102). If you look carefully, you will see this joint as a slight bulge in the trunk, which should lie a short distance above the ground. The scion is taken as a cutting from the desired cultivar (because most fruit trees are cross-pollinated, they do not grow true from seed), but the rootstock influences certain characteristics of the tree, such as how early in its life it fruits, its susceptibility to certain diseases (such as fireblight), and its tolerance of extreme cold – but especially its size.
Characteristics of different rootstocks
Fruit Rootstock Characteristics
Apple M25
MM111
MM106
M26
M9
M27 Suitable for standard; very vigorous, reaching 6-10m (20-33').
Vigorous. As for M25 but better suited to half standards. No staking required.
Ideal for cordon and half standard, staking required on exposed sites.
Semi-dwarf, to 3m (10').
Dwarf, very productive but poor anchorage so needs permanent staking for support. Ideal for cordons.
Very dwarf, final height just 1.5m (5'); ideal for pots and stepovers.
Pear Quince A
Quince C Suitable for half standard; up to 4.5m (14'6")
Suitable for cordon; produces the smallest pear trees. Height after 5-10 years is up to 4m (13').
Plum or gage St Julien A
Pixy
Brompton Semi-vigorous, up to 4m (13'), for all plums, gages, peaches and apricots.
Dwarf, to 3.5m (11'6").
Vigorous, to 6m (20').
Cherry F12/1
Golt
Gisela 5 Vigorous, to 4m (13') or more.
Semi-dwarf, productive, to 3.6m (11'10")
Dwarf, to 3m (10').
Various rootstocks are available, and they produce trees ranging considerably in size. Fruit trees may be trained into a number of different forms, from full standard (the tallest) through half standard or bush to cordon or espalier (see page 106), so in addition to choosing the right cultivar you need to pick a suitable rootstock for the sort of tree you have in mind. Dwarfing or semi-dwarfing rootstocks are also available, which produce the smallest trees.
In this orchard there is a mix of fruit tree forms: a standard in the background, a half standard in the mid foreground, while at the front are semi-dwarf trees, reaching up to 3m (10').
Buying and planting new trees
Most fruit trees are purchased as one- or two-year-old bare-rooted trees, ready to plant straight into the ground in winter. Bare-root is the most economical way to buy trees, and it usually has a greater rate of success, as the plants get away quickly in spring. You can buy larger, container-grown trees, but these are more expensive and can be harder to establish, as they are more prone to drought in the first years. This is because they tend to be substantial plants with a large shoot area so have a great demand for water in summer, which may not be met by the relatively small rootball.
Planting of bare-rooted stock takes place in late autumn and winter, when the trees are dormant, whereas container plants can be planted at any time. Dig a large hole and place the soil in a wheelbarrow so you can mix in some good compost. For a bare-root tree, knock in your stake just off-centre and on the side of the prevailing wind. Place the tree in the centre of the hole, checking that it will be at the same planting height as it was before it was uprooted (look for the old soil mark on its trunk). Also, make sure that the graft attachment point is above the ground. Then shovel back the soil-and-compost mix, firming with your boots but not so much as to damage the roots. Strap the tree to the stake. Some smaller trees on MM111 rootstocks may not need staking. For a container-grown tree, follow the same approach but knock in the stake at a 45-degree angle just outside the edge of the potted soil, so as not to damage the roots.
Make sure the tree is well watered during the first summer – give it a good soaking once a week – and keep the area around it clear of weeds by mulching. Don’t let the trees fruit for a few years, so remove any blossom in spring.
Mycorrhizal fungi
Whether you buy bare-rooted or container-grown trees, it is also beneficial to use a mycorrhizal fungal powder or gel to help it establish. Mycorrhizae are symbiotic associations between certain specialist fungi and the roots of plants: the fungus colonizes the plant roots and forms what can be considered as a second root system, extending the plant’s own root network and enabling it to take up nutrients from a much greater area of soil. In return, the plant provides the fungus with sugars. Mycorrhizal fungi are found in soils naturally, but in poor soils there may be fewer present, so adding a mix of mycorrhizal fungal spores to the planting hole ensures a good start. The young plants grow a denser root system that leads to strong growth and less susceptibility to drought.
Grafting your own trees
Fruit trees are not cheap to buy, even young ones. If you are planning on planting a number of fruit trees or you intend to propagate material from a heritage orchard, you may want to consider grafting your own. Grafting involves attaching a scion (a cutting) from a donor tree to a rootstock, so that the two parts join together to form one plant. The rootstocks that you use for grafting are much cheaper to buy than young trees, although it does take a bit of practice to perfect the technique, so expect a few failures.
There are several different ways to graft, but the basic method is the same: the scion is lined up with the rootstock and the join sealed. It’s important to use a sharp knife to get a clean edge and to try to line up the cambium (the actively dividing tissue in the stem of the plant) in the scion and the rootstock. Once they are in close contact and held tight, the cut surfaces form a join. It is important that the cutting is dormant, but the rootstock can be either active or dormant. ‘Splice’, ‘whip-and-tongue’ and ‘saddle’ are all types of graft where the cutting and rootstock are o
f the same diameter. When the rootstock is larger in diameter than the cutting, a ‘side’, ‘cleft’ or ‘wedge’ graft is used. The diagram here illustrates a whip-and-tongue graft.
Pruning
Regular pruning is essential. If you leave it several years, you end up with a big job that takes hours and also necessitates a hard prune, which will set back the tree. If you do a small amount each year, the impact on the yield will be minimal. The aim of pruning is to develop an open shape with good air circulation, which reduces the risk of disease and lets more light in to get a good crop yield. The subject of how to prune is covered in many books, but if you are not confident, go on a course or ask someone with experience to come in and demonstrate how to do it.
Most pruning takes place in winter, although you may need to do summer pruning on vigorous trees and on stone fruits (apricots, peaches, plums) to lessen the risk of spreading the fungal disease silver leaf. You will need sharp secateurs and loppers or a pruning saw. First, remove any dead, diseased or dying branches. Shorten recent growth on each main branch by about a third, to stimulate the formation of new branches and spurs. Don’t touch the new side shoots, as these will develop new fruit buds (assuming the tree is spur-bearing – see page 98), unless they are crowding out other shoots or crossing or growing towards the centre of the tree.
Training fruit trees
Fruit trees can be trained to grow into a certain shape, such as a fan. The main reason to train a fruit tree is to take best advantage of the available space, for example against a sunny wall. It is also thought to improve the fruit, leading to fewer but larger and better-tasting fruit, as the trees put all their energy into fruiting rather than into producing more leaves.
Among the most popular trained forms are cordons, fans and espaliers, which are ideally suited to growing against a wall or to creating a vertical barrier on the plot, using a trellis or similar support system. With these forms of training, the trees get more light and better airflow, which helps the fruit to ripen and reduces the incidence of disease such as mildews. Growing fruit trees against a wall also allows you to take advantage of the microclimate and to grow varieties that need more warmth, such as apricots and peaches, while a trained tree is also easier to protect from frost and birds.
Cordons
When space is in short supply, a cordon-trained tree can enable you to produce a relatively sizeable harvest. A cordon is a tree that has a single stem with lots of short, stubby side shoots which bear fruit. This form is suitable for spur-bearing apples and pears, since these fruit on short side shoots, and the yield can reach as much as 10kg (22lb) per cordon. Tip-bearing varieties are no use, as the tips will be pruned, so you would never get any fruit. Cordons are very useful as internal dividers on the plot.
Typically, cordons are grown in a row, each tree planted at an angle of 45 degrees, but there are variations, such as the ‘U’, with two vertical branches, or even versions with three or four verticals per tree. It’s important not to use vigorous rootstocks, as they are difficult to control. If you grow a mix of cultivars, you shouldn’t have to worry about pollin ation, and can also get a useful combination of cooking and dessert fruit.
In this vegetable garden, fruit cordons have been trained to form a decorative arch.
A cordon is usually trained at an angle of about 45 degrees, with close planting of 70cm (28") between the plants in the row. Support is essential, so a cordon is planted against a wall or fence or supported with posts about 3m (10') apart, with a framework of three or four horizontal wires about 50-60cm (20-24") apart.
When planting, ensure not only that the grafting join is above the ground but also that the wood above the graft is uppermost and that the line of the join points towards the ground, to reduce the risk of the trunk breaking. Tie long bamboo canes to the wires at a 45-degree angle to support the young trees.
Cordons need a strong framework of supporting wires, fixed to a fence or wall or to sturdy stakes.
Suitable rootstocks for cordons are M27, M9 and M26, depending on the soil type, and Quince C. On poorer soils it can be better to choose slightly more vigorous rootstocks. If you have multiple rows of cordons, leave a space of around 60-70cm (24-28") between rows. Once planted, cut back any long side shoots to three buds and leave the leader (main) shoot unpruned. Cordons should be pruned in late summer by cutting back any new shoots that exceed 20cm (8") or three leaves above the basal cluster of leaves (the cluster around the base of the current year’s growth). Leave any shorter new shoots. New shoots on existing side shoots are pruned to one leaf above the basal cluster, and any upright growth is removed. Allow the cordons to reach an eventual length of 2m (6'6") but no more, so harvesting is easy.
Fans, espaliers and stepovers
These differ from cordons in that the trees have a number of branches. In the case of an espalier, the branches extend out sideways from the main stem, while in a fan the branches radiate out. The best apple rootstock is MM106, or M111 on poorer soils, and for pears Quince A. Use St Julien A for plums, apricots and peaches. Support is essential for fans and espaliers, so they need a framework of horizontal wires spaced at 40cm (16"). Allow 4-6m (13-20') between plants.
Any fruit tree can be trained into a fan. A one-year-old grafted tree (known as a maiden) is cut to 60cm (24") in autumn, and the following spring four to six buds are allowed to grow as branches. These are trained by attaching them to the wire framework to create radiating arms.
Espaliers are also produced from maiden trees. The tree is cut back to a bud that lies about 15cm (6") above the lowest wire. This bud is allowed to become the vertical branch, and the shoots from the next two buds below are trained, one to each side, to create the first tier of branches. This is achieved slowly, by gradually tying the shoots down so that they are eventually lying horizontal and are tied to the wire (but not too tightly). This process is repeated in subsequent winters, so that several tiers of shoots are produced.
A stepover is simply an espalier with just one tier, and the main leader tip removed. Like cordons, they are useful for growing around large vegetable beds and dividing up areas of the plot.
It is important to prune these trained trees regularly to maintain their shape. In late summer, fans and espaliers should be pruned by cutting back new side shoots to three leaves from the basal cluster, while shoots on existing side shoots can be cut to one leaf above the basal cluster. Any suckers from below the graft should be removed.
A row of fruit trees trained as espaliers can create an attractive and productive boundary.
Soft fruit
Soft fruit is expensive to buy, so it is an obvious choice for the small plot. With careful planning you can harvest soft fruit for 8 months of the year, starting with early strawberries under cover in early spring and ending with autumn raspberries, which can be harvested until the last frosts. For the remaining months you could rely on soft fruit in the freezer.
Fruit cages
Soft fruit tends to be grown in blocks of space, simply because the juicy fruit needs protection from birds and the easiest way to achieve that is to build a fruit cage. You can grow them in rows where space allows, and cover them with netting, but expect some losses.
Commercial fruit cages have a tubular frame with polypropylene mesh over the sides and roof. Most of the modular systems that are available are based on 2m (6'6") lengths. However, a fruit cage is relatively easy to construct should you wish to save money and build your own. Also, you only need a tall walk-in one if you are growing raspberries; a lower one would suffice for currant bushes and strawberries, although it’s not so easy to manage.
The netting on a fruit cage can be damaged in winter if there are high winds or heavy snow, so often it is taken down in autumn.
Ideally, a fruit cage should be positioned on a level site in full sun or in sun and partial shade, and avoiding a site that might catch any late frosts. A space as small as 4m x 4m (13' x 13') is enough to accommodate a number of bush plants such
as blackcurrant, redcurrant and whitecurrant bushes, jostaberries, gooseberries and several rows of raspberries and blackberries, as well as strawberries and rhubarb. Don’t forget to leave space to move around between the rows of plants once they are mature! The cage pictured above is 7m x 5m (23' x 16').
Soft fruit are permanent crops, so it pays to clear the weeds thoroughly and prepare the soil well. The soil needs to be free draining with good fertility. Either dig over the site to remove any compaction and perennial weeds and mix compost into it, or, if you are using the no-dig method, cut any vegetation close to the ground, ease out any large perennial weeds and cover with cardboard and a thick layer of compost. You can plant directly into this.
To reduce the growth of future weeds you could cover the ground with bark chippings, but be aware that they take up nitrogen from the soil as they rot down (see Chapter 3, page 50). I prefer to cover my no-dig plots with ground-cover fabric to suppress any weeds, as well as to conserve water. If you don’t use a ground cover, take care not to hoe too close to the bushes, as soft fruit bushes have relatively shallow roots that can be damaged easily.
Poultry in the fruit cage
Don’t forget to maximize the use of the ground in the fruit cage. If you have grassy areas between the rows of plants, you could use the space for birds. Chickens are the obvious candidates, but it’s not wise to have them in the cage from the time the fruit buds are forming until leaf drop. But the winter months, when the plants are dormant, are perfect, as the chickens cannot do any damage and will clear the ground of insects and other pests. They are particularly good at clearing away overwintering sawfly pupae, which devastate gooseberry plants. The chickens will scratch, unless you have feathered legged breeds such as Brahmas, but this could help to keep the beds weed-free. Watch out for them creating deeper dust-bath areas, which would damage the shallow roots of the fruit bushes.