RedcurrantRibes rubrum

The currant is sold as a bush, on its own roots, or grafted on a stem of Ribes aureum at 80 or 100 cm high. The bush lives longer and renews itself from the base; the standard form frees the ground, keeps the strings clean and can be picked without bending, but it needs a permanent stake and rarely lives more than fifteen years. For a small garden or the edge of a vegetable plot, alternate the two. Vertical cordon varieties, with one or two stems trained on a wire, give longer strings at only 50 cm spacing. Always buy a two-year-old plant, with three or four well-spaced branches.

The redcurrant fears dry heat more than shade: in our gardens, the partial shade of an east-facing wall or a north-west hedge suits it perfectly, provided it gets four hours of sun. Avoid frost pockets where fog lingers in April, the flowering period, and windswept spots that dry out the shallow roots. Moist loamy soil, even clay, is ideal; sandy soil will need a thick mulch and consistent watering. Allow access from two sides for picking and laying a net.

A month before planting, carefully weed out bindweed and couch grass, which would otherwise smother the shallow roots. Dig a hole 50 cm each way, a little more in compact clay, breaking up the bottom with a garden fork. Mix two or three spadefuls of mature compost and a handful of bonemeal or hoof and horn into the excavated soil. On heavy ground, work coarse sand or fine gravel into the bottom, without creating a sealed basin. Let the soil settle for a week before planting.

Bare-root planting, from October to March outside frosty spells, remains the best: cheaper plants, more vigorous establishment. Trim damaged roots, dip them in a slurry of soil and compost, then set the plant with the crown buried 5 cm for a bush, which multiplies shoots from the base. For a standard, keep the crown at soil level and drive the stake in before the shrub. Fill in, firm at the base, water with ten litres even if it is raining, and cut each branch back to a third to form a low, sturdy framework.

The redcurrant does well in a container on an east- or west-facing terrace, in a container of at least 40 litres, with holes, filled with potting compost mixed half and half with garden soil and compost. A standard form is the most elegant in a pot and takes up little room. The sensitive point is watering: the growing medium must never dry out in June, nor become waterlogged in winter. Mulch the surface, top-dress with compost each spring and repot every three years, trimming the root ball. Allow two kilos of fruit per mature container.

The first mistake is planting in full sun against a south-facing wall: the strings scorch and the shrub exhausts itself. The second is hoeing: the roots run 10 cm below the surface and every stroke of the hoe injures them; mulch instead. You also see shrubs planted too close, at 80 cm, which become impossible to pick and encourage powdery mildew. Finally, do not skip the planting prune: a plant left intact fruits sooner but builds a bush bare in the centre, which will need severe renovation three years later.

A one- or two-year-old redcurrant still has a limited root system: water every week in dry weather from April to July, ten litres at the base, poured slowly. The critical period runs from flowering to the swelling of the berries, in May and June: a lack of water then gives short strings and fruit that drops. After the harvest, the shrub tolerates drought but is preparing next year's buds; a watering in August during a heatwave is not wasted. Once mature, a thick mulch alone is enough in most Belgian summers.

Mulching is the central task: a layer of 8 to 10 cm of wood chippings, dried grass clippings or dead leaves, renewed each spring, keeps the soil cool and avoids any hoeing. Under the mulch, spread in March two or three spadefuls of mature compost and a handful of sieved wood ash, rich in potash, which the redcurrant appreciates. Avoid fresh manure and fast-acting nitrogen fertilisers, which give soft shoots overrun with aphids. On poor soil, a handful of sulphate of potash in February corrects potash deficiencies.

For the first three years, form a bush of eight to ten upright main branches by cutting the leaders back by half each winter to an outward-facing bud. After that, fruiting pruning is done each winter, between December and February: remove at the base one or two branches over four years old, recognisable by their dark, scaly bark, take out prostrate wood and shoots in the centre, then shorten the current year's side shoots to two or three buds to create fruit buds. On cordons, pinch the side shoots to five leaves in June.

The currant blister aphid, which puckers the leaves red, is fought by spraying soft soap from April and avoiding nitrogen; the ladybirds then take over. The gooseberry sawfly, a green false caterpillar spotted with black, can strip a bush in a week in May: inspect the heart of the shrub and crush the larvae. Against powdery mildew, open up by pruning and spray milk diluted to 10 % or a horsetail decoction. The net against blackbirds, laid over a frame as soon as the strings blush, remains the most worthwhile protection of all.

In February, prune and add compost and ash. In April, watch for the first aphids under the young leaves and lay a fleece if a frost threatens the flowering. In May, water if the month is dry, that is the most important. In June, stretch the net, pick the red strings from the end of the month, and harvest the whites in July. After the harvest, remove the net, top up the mulch and leave the shrub alone. In autumn, gather fallen leaves if rust spots have appeared. A notebook of dates helps a lot from one year to the next.

Beyond the basics, know that the currant gains from staying a week longer on the bush after full colouring: the sugar rises and the acidity softens, especially for the white varieties. Pick string by string with the stalk and lay them in shallow punnets so as not to crush those underneath. For jelly, mix in a third of slightly less ripe strings, richer in pectin. Strings washed then dried on a cloth freeze whole on a tray, which lets you strip them frozen, without damaging them.