1] Plant only virus and disease free stocks
To get the best you have to start with the best! Fruit trees are available from many sources, not all of them traditional or specialist. You need to know the origins and exactly what you are buying because if you start off with a tree with some inherent disease it will always be at a disadvantage and may never fully recover. A lingering disaster that takes up valuable space – and money, for years and years, is not what you want at all. Certification schemes exist for soft fruits, and the stocks used to propagate fruit trees. Be sure to ask the Nursery, or to buy from a source that advertises such as stock, before investing your pennies.
2] Avoid high nitrogen fertilizers
This might seem a strange one as feeding so often helps the vigour and general health of a plant. Nitrogen is a fertilizer that promotes growth. It’s ideally used on plants and trees that are struggling or have low vigour. However too much of it produces too much growth. This growth will be ‘soft’ and that’s just the type of growth that attracts aphids, blackfly and greenfly. Very unwelcome insects that will spread diseases. So try to aim for a hardy and not excessively vigorous tree and only feed with nitrogen if it seems stunted or reluctant to produce any new growth.
3] Grow flowers amongst the fruit!
Pollen and nectar rich flowers attract beneficial insects which in turn will help rid your fruit of unwelcome visitors. Creating a natural mini biodiversity will provide a natural response if your stock is attacked by insects or disease.
4] Pruning is key
When pruning try to aim for an open framework of branches. The more air circulation you can get the better because a close atmosphere and lots of congested, leafy growth is the ideal environment for moulds, mildew and other fungal diseases. Creating an open airy structure to fruit trees allows the sun and air in and also makes sure the foliage dries more quickly after rain.
5] Plant disease resistant varieties
When selecting varieties you want to grow read up and research the available choices. Some of the newer varieties – and this includes all major fruit types – have increased levels of disease resistance which make them much easier to grow and less problematic. They will always be cleaner than a variety that does not have such disease resistance. And, unless your experienced and willing to apply chemicals, avoid known problem varieties such as Apple Cox’s Orange Pippin and Strawberry Royal Sovereign, no matter how tempting they may be!
Healthy growth like this relies on best cultural practices....