Growing Soft Fruit Plants in Containers
There are very few garden plants that can’t be grown in containers although I have to say that soft fruit don’t make particularly successful subjects. This is largely because most types are fairly shallowly rooted and, therefore, prone to drying out. Any plant in a container will suffer more easily from water shortage than one in the open garden; and water shortage in a fruiting plant means poor quality fruit. All of these factors can lead to problems, but if you are prepared to devote more than the normal amount of attention to watering and plant initially with care, then it is possible to obtain modest crops of soft fruit, even on a paved area by someone with no real garden.
TYPES OF CONTAINERS
Because of their small size, are the most amenable of soft fruit to container cultivation. For all other types of soft fruit, a container approximately of half-barrel size is needed — around 50cm (20in) in both height and diameter. Genuine wooden half barrels are suitable provided holes are made in the bottom and the inside is lined with plastic sheeting to prolong the life of the timber. Alternatively, use terracotta, if you can afford the high cost of large pots. Plastic containers will suffice, however they will never look as attractive and are quite likely to crack and split after a few years.
It is very important to use a good quality growing medium and for these long-term crops, a-based type such as John Innes No. 3 potting compost is ideal. The only exception to this are blueberries which must have a highly acid medium and can only be grown in ericaceous compost of the type sold for growing rhododendrons and camellias. Although soil-based composts are well furnished initially with nutrients, regular feeding will be necessary after the first six months or so and my general advice is to follow the fertilizer regimes that I have outlined under each plant entry for normal outdoor growing but supplement this with liquid feeding. Apply a proprietary tomato fertilizer or similar product with a high potash content about once every two weeks.
Regular watering is of utmost importance, especially when the fruit are beginning to form – but don’t forget to apply a thick mulch too. Pulverised bark is a good choice and also an attractive one and should be applied when the compost is damp — once in the spring and again in the autumn.
Pruning and pest and disease control should be done exactly as if the plants were growing in the open soil but you should be prepared for slightly more pest and disease problems if, as is generally the case, the container is positioned in a relatively sheltered spot.