The currants are some of the most easily grown fruit bushes. Redcurrants, and whitecurrants are both cared for the same way. They produce tasty nutritious fruit and they are also just pretty little bushes. They are hardy and can grow in colder locations than blackcurrants and on poorer ground. Redcurrants and whitecurrants are both completely self-fertile, so you only need one plant for a crop. They prefer good, well-drained soil with a neutral pH to slightly acidic.
Position redcurrants in full sun and ensure that they are protected from drying winds which will tend to reduce the size of the fruit. Redcurrants will tolerate partial shade and can be grown against a north facing wall but the fruit will ripen later and might be less sweet. Obviously, it's best to incorporate plenty of well rotted organic matter and a handful of bonemeal per plant deep into the soil before planting.
Redcurrants and Whitecurrants can be grown in three main formats: bushes cordons or fans. Plant between November and the beginning of March. Keep the roots damp (in a bag with something wet inside) right until you are planting them. Do not leave them in water as they drown. When you take a currant out of the bag to plant it, cut back any damaged roots.
Bush plant 1.5m apart 1.5m between the rows
Cordons plant 50cm apart 1.5m between the rows
Fans - Plant 2 metres apart
Wet the roots in a bucket of water and put the red or whitecurrant in a hole with plenty of room for its roots and so the plant will end up with the finished soil level at the same point as before lifting (usually seen as a root collar or "high water" mark on the main stem). Replace the soil, and firm it down with the ball of your foot. Water well.
Weed control after planting matters - weeds provide unwanted competition and so affect crop size. A heavy mulch in early spring (straw or other organic matter is good) helps to suppress weeds, is good for moisture retention and eventually rots down and improves the ground. It also helps stop damage to the feeding roots of redcurrants, which are shallow.
All pruning carried out in the first couple of years creates the form of the plant. Most pruning is done in the late winter or early spring when it is not freezing. A bush, grown on a leg which is 10-15cm of bare stem from the ground up, with an open centered, bowl shaped plant is the favoured form. This is done in the same way as for Gooseberry bushes, with one small but important difference: where gooseberries are a bit droopy, making it wise sometimes to prune them back to an inward and upward facing bud, Red and Whitecurrants should always be pruned back to an outward facing bud, as is normal for most plants.
Ideal for situations of limited space, Cordons can be trained into a single, double or triple stem plant. Remember that support via a wall or wire frame will be required: a good long bamboo cane is enough for single stem cordons.
February Fertilising: You can spread N-P-K fertiliser around your plants in late Februaury as per their instructions, just before their roots begin to wake up, with about 30g per square metre of Sulphate of Potash (Potassium sulphate) added in. This will make a big difference to their productivity and flavour. Mulching is always good too (if you have poor soil and no mulch, spreading sulphate of ammonia around is also good - about 50g per square metre).
Water very well in dry periods until you have finished picking. There is no need to water in winter.
Protect your fruit from birds as the fruit start to change colour with a fruit cage or netting over the plant.
Currants are carried in strings 10-20 berries. When really ripe, they are soft and a deep, rich red. Harvest by taking off each string; a strong pair of scissors helps. For jelly, pick them when they are still a little unripe as there is more pectin in the fruit and the jelly sets better. Leave until they are fully ripe for everything else. Red & whitecurrants freeze well.