Redcurrant

Redcurrant plants: red, white and pink varieties

Redcurrants are cultivated principally within the species Ribes rubrum and closely related European currants. They produce strings of small translucent berries that may be red, white, cream or pink according to the cultivar.

Whitecurrants and pink currants are not separate fruit species. They are forms of redcurrant with little or modified skin pigmentation and are planted, pollinated and pruned in the same way.

Redcurrants are well suited to cool temperate climates across northern, western and central Europe. Dormant plants tolerate cold winters and their fruit does not require an exceptionally hot summer to ripen.

Success depends more on soil quality, moisture during fruit development, protection of the flowers from late frost and pruning that preserves the correct fruiting wood.

Redcurrants should not be pruned like blackcurrants. Blackcurrants crop mainly on relatively young branches, whereas redcurrants produce much of their fruit on short spurs carried by branches that are two years old or older.

What is the difference between red, white and pink currants?

Useful characteristics when choosing a redcurrant cultivar

One redcurrant plant is normally sufficient for fruit

Red, white and pink currant cultivars are generally self-fertile. One plant can therefore produce fruit without another cultivar nearby.

The flowers are nevertheless visited by bumblebees, honeybees and other insects, whose activity helps produce well-filled and regular strings.

Self-fertility means that pollen from the same cultivar can fertilise its flowers. It does not mean that pollinating insects and favourable flowering weather are unimportant.

Cold, wind, prolonged rain or frost during flowering can reduce fruit set even on a healthy self-fertile plant.

Several cultivars can be planted to obtain different colours, flavours and harvest periods, but they are not normally required to pollinate one another.

There are no separate male and female redcurrant plants that must be paired.

Winter hardiness and late spring frost

Dormant redcurrant wood is very winter hardy and withstands the cold conditions found across much of temperate Europe.

Open flowers and newly formed berries are much more vulnerable than dormant branches.

A spring frost may destroy part of the crop without causing lasting damage to the plant itself.

Avoid frost pockets, enclosed hollows and the bottom of slopes where cold air accumulates during clear nights.

Redcurrants do not need the warmest wall in the garden. An exceptionally warm south-facing position can advance bud break and flowering, increasing exposure to late frost.

A bright but relatively cool and well-ventilated position is often particularly suitable in northern and maritime climates.

Sun or partial shade?

Full sun generally increases crop size, berry colour and sugar concentration.

Redcurrants nevertheless tolerate partial shade better than many fruit crops and can produce against an east- or north-facing wall.

With less direct sunlight, the fruit normally ripens later and retains more acidity.

Light afternoon shade may be beneficial in hot and dry regions, where intense sun can scorch exposed berries and accelerate soil drying.

Avoid deep shade beneath large trees. Root competition and insufficient light produce weak growth, short strings and fruit with limited sweetness.

A bright woodland edge or a position receiving sun for a substantial part of the day can remain suitable.

Soil, moisture and drainage

Redcurrants prefer deep and fertile soil containing useful organic matter, remaining moist during fruit development while draining adequately in wet weather.

Structured clay soil can produce excellent results because it stores water during spring and early summer.

Compacted clay that remains continuously saturated restricts oxygen around the roots and weakens the plant.

Redcurrants tolerate soils ranging from slightly acidic to moderately calcareous.

Very calcareous, shallow and dry ground may limit growth, while sandy soil requires more organic matter, mulching and regular watering.

The root system is relatively shallow and competes poorly with dense grass.

A plant may remain alive in dry ground while producing short strings of small and exceptionally acidic berries.

Maintain a weed-free or mulched area around the plant, especially during establishment and fruit swelling.

Planting a young redcurrant

Dormant bare-root and container-grown plants are preferably planted between autumn and early spring whenever the ground is neither frozen nor waterlogged.

Autumn planting is particularly suitable in drained soil because the roots can begin establishing before the following growing season.

A container-grown plant already carrying leaves or flowers is less resistant to late frost than a dormant established bush.

Where the plant has started growing under protection, wait until the principal frost risk has passed or provide temporary protection during cold nights.

Prepare a broad area of soil rather than a narrow hole filled with potting compost.

Work the ground only when it has drained sufficiently to form a fine crumbly structure and remove couch grass, bindweed and other perennial weeds carefully.

Plant the redcurrant at approximately the depth at which it grew in the nursery, retaining a short clear stem above the ground.

Unlike a bush-form blackcurrant, it does not normally need to be planted deeply to encourage numerous new stems from below soil level.

Backfill mainly with the original soil, improved across a broad area with mature compost where required.

Avoid placing fresh manure, concentrated fertiliser or a small pocket of pure compost directly against the roots.

Water thoroughly after planting and maintain a weed-free root zone.

Continue watering throughout the first growing season whenever rainfall is insufficient, rather than caring for the plant only during the first few weeks.

Which wood carries the redcurrant crop?

Redcurrants produce fruit near the base of shoots formed during the previous season and on short fruiting spurs carried by branches that are two years old or older.

These spurs can remain productive for several years when they continue to receive sufficient light.

Branches should therefore not be removed simply because they have already carried fruit.

This distinguishes redcurrants from blackcurrants, whose best crops are associated more strongly with younger wood and which require faster branch renewal.

As redcurrant branches age, they eventually become weak, heavily branched, shaded or strongly arching.

These old framework branches should then be replaced progressively by strong and well-positioned younger shoots.

How should a bush redcurrant be pruned?

Maintain a short clear base and an open framework containing several main branches of different ages.

Light and air should be able to reach the centre of the bush.

During dormancy, remove dead, diseased and broken wood, branches lying on the soil, crossing growth and shoots directed towards the congested centre.

Gradually remove the oldest framework branches when their growth and fruiting decline.

Retain strong young branches capable of renewing the structure.

There is no need to replace a large proportion of the bush every year because redcurrant branches remain productive for longer than blackcurrant canes.

Lateral shoots can be shortened to maintain compact and well-lit fruiting spurs.

Avoid excessive pruning on a weak or recently planted bush, as the plant requires enough leaf area to establish and produce replacement wood.

Do not trim a redcurrant like a hedge by cutting every shoot to the same outline.

Hedge trimming creates dense external growth, shades the centre and makes the strings more difficult to see and harvest.

Bush, cordon or fan-trained redcurrant?

Watering, mulching and feeding

Water availability is particularly important between flowering and harvest.

Drought reduces berry size, shortens the strings and increases the perceived acidity of the fruit.

Water sufficiently to moisten the complete root zone rather than applying small quantities to the surface every day.

Allow the soil to regain air between waterings and adjust the frequency according to weather, soil texture and mulch depth.

An organic mulch applied to already moist soil reduces evaporation and competition from weeds.

Keep the mulch slightly away from the base of the branches so that the short clear stem remains visible and relatively dry.

A moderate annual application of mature compost is normally sufficient in good garden soil.

Excessive nitrogen produces long tender shoots, dense foliage and greater susceptibility to aphids and fungal diseases.

How can fully ripe currants be recognised?

The berries should have developed the characteristic colour of the cultivar throughout the string.

Redcurrants become translucent and glossy, while white cultivars develop an ivory or pale yellow colour and pink currants acquire their final blush.

Skin colour may appear before full eating maturity.

Where birds and weather allow, leaving the strings on the plant for several additional days often reduces acidity and develops a fuller aroma.

Fully ripe berries are juicy, slightly softer and detach more readily from the string.

Currants do not become significantly sweeter or more aromatic after picking.

Harvest at the stage suited to the intended use: slightly firmer for handling and jelly, or completely ripe for eating directly and preparing desserts.

Redcurrant harvest season

Early cultivars begin ripening near the start of the currant season, while the latest varieties can extend harvesting for several additional weeks.

Actual dates vary according to cultivar, country, exposure, crop load and seasonal temperatures.

A harvest calendar is therefore most useful for comparing cultivars rather than predicting one exact picking date for every garden.

Harvesting and storing currants

Pick during dry weather and remove the complete string rather than detaching every berry individually.

Keeping the fruit attached to the string reduces crushing and allows the berries to be stripped immediately before use.

Place the crop in shallow containers and cool it promptly.

Avoid deep bowls or buckets in which the weight of the upper fruit crushes the berries beneath.

Currants generally keep for several days under refrigeration when they are dry, healthy and remain attached to their strings.

Do not wash them until shortly before use because surface moisture encourages deterioration.

Currants freeze very successfully. Strings can be frozen whole, after which the hardened berries are easily removed with a fork.

Uses for red, white and pink currants

Redcurrants are especially valuable for jelly because their juice combines acidity, colour and natural pectin.

They are also suitable for coulis, syrups, sauces, juices, tarts, cakes and desserts requiring a fresh and sharp fruit.

Whitecurrants and pink currants are often milder and particularly attractive for fresh eating, fruit salads and decoration.

Their pale or pink colour allows them to be combined with other berries without producing an intensely red preparation.

Currants can also be mixed with sweeter fruit such as strawberries, raspberries, apples or pears to provide acidity and improve the balance of jams and compotes.

Important pests and diseases

Which redcurrant plant should you choose?

For jelly, juice and coulis, choose a productive red cultivar with concentrated flavour and sufficient acidity.

For eating directly from the plant, consider a mild redcurrant, whitecurrant or pink currant with fine skin and good flavour at full maturity.

For quick harvesting and attractive desserts, choose a cultivar carrying long and evenly filled strings.

For an extended season, combine early, mid-season and late varieties.

For a small garden, choose a compact cultivar or train the plant as a cordon.

For abundant production with straightforward maintenance, a conventional bush remains the simplest form.

In dry soil, cultivar choice cannot replace improving water retention, mulching and irrigation.

In a humid position, an open and regularly renewed framework reduces the persistence of moisture within the foliage.

Above all, preserve the adult branches carrying productive spurs rather than pruning redcurrants according to the faster renewal system used for blackcurrants.