Raspberries are unusual in that their roots and crowns are perennial, while their stems or ‘canes’ are biennial. This basically means that your raspberry plant will go on and on. However, the branches (or canes) which bear the fruit live for only two summers making pruning especially important. During the first growing season, the shoots of summer raspberries will not fruit - these are called primocanes. The following year these canes will flower and produce fruit and are now called floricanes. The floricanes produce their fruit in early to mid summer and then die back. New primocanes are produced each year, so fruit production continues year after year. Your main task is to prune out the dead canes each year. Autumn fruiting varieties however produce fruit at the tip of the current season’s growth. It sounds far more complicated than it is! Once you have established which variety you are growing and how to handle the pruning regime there is perhaps no better soft fruit to grow for a prolific and delicious crop.
Planting Raspberries
Although it is possible to grow raspberries from seed, by far the most common and straightforward way to cultivate them is to plant as bare root canes – usually available from nurseries and garden centres.
Soil and Aspect
Like most fruit, raspberries thrive in an open sunny site, but they will tolerate some light shade. They prefer a deep, well drained but moisture retentive soil with a pH of around 6.0 to avoid iron deficiency.
Cultivation
Raspberries, whether bare-rooted or container-grown, should be planted out in late Autumn or early Winter. Plant them a little deeper than they were previously growing (you’ll be able to see a soil mark on the stems of bare root plants) and space 45cm apart with 1.5m+ between rows. Cut the canes to 15cm above ground and water thoroughly after planting. Raspberries need very little or no feeding, but a mulch applied in the Spring will give the a nutrient boost.
Pruning Raspberries
Summer Fruiting Varieties
These need to be pruned twice. In early or mid-Spring remove all weak or damaged canes to ground level. Leave the most vigorous canes and aim to have them spaced around 15cm apart. After fruiting remove the spent canes – they will be brown in colour – to ground level after the last harvest of the summer to encourage growth of new shoots the following year.
Autumn Fruiting Varieties
In early Spring prune back all canes to ground level – no Summer pruning is necessary
Harvesting and Storage
Raspberries should be picked early in the morning before it gets too hot and are best eaten straightaway. They can be frozen or made into jam too – they do not keep particularly well in the fridge.
Pests and diseases
The main diseases that commonly affect raspberries are botrytis (a fungus that affects many plant species) and mildew. Keeping on top of pruning and watering will help avoid these. Deter birds with a Birdscare tape and protect your crop with a Round Fruit Cage to make sure you get to enjoy a bumper harvest.