Plums are one of the great unexplored parts of the fruit world. In the past there were many different varieties, all with different flavours and textures, but now all knowledge of such fruit seems to have been lost. At most, one or two varieties surface occasionally in shops, but few people seem to know of the treasury of delights that could be available. Fortunately, many of the old varieties are available from specialist nurseries, and anyone who takes the trouble to search them out is really in for a treat.
In general, plums like a sunny situation, but there are plums for all sorts of climates and you may well find that some are better suited to local conditions than others.
Plums are mainly grown as trees, varying from full-sized standards to spindle bushes and pyramids. They can also be trained as fans. Unfortunately, they cannot be grown as cordons. Plums trees are not usually large and can be accommodated, even in small gardens.
Damsons were traditionally grown as hedgerow trees and can be planted in a hedge, saving a lot of space and yet producing a good crop of fruit. Plums vary in fertility, some being self-fertile, but they all do better for having a pollinator in the area,
Plums must have a sunny position; in cooler areas, a position against a wall will be ideal. They flower early and so should not be planted in frost pockets, where the blossom will be lost. The soil should be fertile and moisture retentive, although they will tolerate drier soil than many other tree fruits. Plant the trees at any time between autumn and early spring, as long as weather and soil conditions allow. Planting distance will vary from 3m/10ft to 7.5m/25ft, depending on the size of tree. Fan-trained trees will need to be 3-4.5m/10-15ft apart. Smaller trees and fan-trained varieties should be covered if frost threatens while they are in blossom. Mulch in early spring with a good layer of organic material. If the crop is heavy, thin the fruit as soon as the stones begin to form. Thin so that they are 5-8cm/ 2-3in apart.
Pruning and training
Any pruning should be carried out in summer to reduce the chances of the tree being infected with silver leaf. Once the initial shape has been determined, larger trees do not need any pruning apart from the removal of dead or damaged wood. On fans, remove all new shoots that face towards or away from the wall. Shorten any retained new growth to six leaves.
Harvesting and storage
For cooking and preserving pick a little earlier, just before the fruit is ripe. Keep the stalk on the fruit as you pick them. They can be frozen or bottled for storage, but it is best to remove the stones first.
Pests and diseases
Wasps and birds can cause problems as can larger animals such as rabbits and hares. Other insect pests include aphids and winter moths. The main diseases are silver leaf, canker and brown rot. Trees that are affected with silver leaf and canker should be burnt or destroyed at once.