Blackcurrants have got bigger and, it’s claimed by breeders, sweet enough to eat straight from the plant. Whether you want to grow them for fresh fruit, juice, desserts or sauces, blackcurrants are easy to care for and produce great crops.
Yield per plant: 480g
This variety is said to give some of the largest fruits that are sweet enough to eat on their own. And we agree. The currants, on short strigs (branched stalks), were huge: about three times normal size. They were very juicy and had no noticeable acidity. Our plants weren’t troubled by the aphids that damaged others either, so despite a lower yield, we made it a Best Buy.
Yield per plant: 1400g
The fruits of this variety were low in acidity and relatively high in sugar. They did have a strong ‘blackcurrant’ taste, but the sweetness made them pleasant enough to be eaten on their own straight from the plant. We found the size of the currants varied a lot, although most were large, and the strigs were short but plentiful. The plants didn’t attract aphids either, so stayed healthy.
Yield per plant: 880g
The large currants had a strong blackcurrant flavour and were slightly less sweet, but should become sweeter the later they’re picked. They suffered from aphid damage early on but recovered well. They flower later than other varieties, so would be useful in an area prone to late frosts.
We planted three of each variety at Capel Manor Gardens in north London in autumn, and assessed crops two years later. To get an objective assessment of the sweetness of the blackcurrants, we used a Brix refractometer. After a very warm early spring, our currants ripened a week or two earlier than expected. Crop levels were also lower than you’d expect from a mature bush as we only grew them for two years. We had no disease problems, but in early spring some varieties became infested with aphids, which damaged emerging leaves.
Grow in well-drained, moist soil with added well-rotted manure, preferably in full sun or light shade. Space bushes 1-1.5 metres apart and put them 5cm deeper than the previous planting level then trim shoots to within two buds above ground (about 5cm). Winter is the best time to plant them as cheaper bare-root plants are available from fruit nurseries - these also have the advantage of using less plastic and peat in their production that pot-grown plants.
Blackcurrant fruit forms on young wood. During the first three or four winters remove weak shoots. After this, cut out about a third of the older wood at the base and remove weak shoots each autumn/winter.
June to July
Harvest modern varieties by cutting the strigs (fruit bunches) as they turn black. Top currants on older varieties ripen first.
Swollen and rounded buds develop in the winter, and then fail to open normally in the spring. The buds may fail to open or may produce distorted and reduced leaves, and flowering is drastically reduced. This swelling and damage to the embryonic leaves is caused by the feeding activity of microscopic mites within the dormant bud. Plants may crop well for several years after the initial infestation. As they feed, the mites may spread reversion virus.
Tiny yellowish aphids feed on the lower leaf surface, causing blistered leaves, which are initially green but soon turn shades of red and purple. The foliage is often attacked when quite small, but symptoms intensify as the leaf grows. General growth, vigour and cropping are rarely affected.
Small dark-brown spots appear on the foliage of currants and gooseberries in early summer. The spots increase in size and quantity, and the infected leaves discolour and fall prematurely. If the infection is severe, the plant will be weakened and fruits may shrivel.
Stems tunnelled by brown-headed white caterpillars, which are up to 15mm long. Infested shoots may die back and be easily snapped off, revealing a tunnel filled with blackened droppings in the centre of the stem.