Black Redcurrant (Ben Lomond blackcurrant) care

Light

Black Redcurrant needs sun on the leaves, not just bright ambient room light. Full sun gives the heaviest, sweetest crops, but blackcurrants tolerate part shade better than most fruit and still crop usefully in dappled light. Avoid deep shade, which reduces yield and slows ripening. A south or west-facing windowsill in the northern hemisphere is the default; anywhere else, expect the plant to stretch and pale out within a season.

Watering

Outdoor black redcurrant crops want weekly in dry spells, especially as fruit swells; deep soakings rather than little and often. The single best habit is a finger-test before watering — push a finger 3-4 cm into the soil. Damp = wait a day; dust-dry = water deeply at the base of the plant. Blackcurrants are moisture-loving and shallow-rooted, so keep the soil reliably damp from flowering through fruit swell to avoid small berries and premature drop. Mulch thickly each spring to lock in moisture. Reduce watering after harvest.

Soil and pot

Black Redcurrant grows best in rich, moisture-retentive, free-draining loam, slightly acidic to neutral (ph 6.0-6.8). Blackcurrants are hungry, greedy feeders that love deep, fertile soil enriched with plenty of well-rotted manure or compost. They tolerate heavier soils than most fruit provided drainage is adequate; avoid thin, dry, or chalky ground. A pot with a working drainage hole is non-negotiable for this species — even free-draining mix will turn soggy in a closed planter. If you love the look of a decorative pot without a hole, use it as a cachepot around an inner nursery pot you can lift out to water.

Humidity and temperature

Black Redcurrant sits happiest at around 40-70% humidity and 10-24°C (50-75°F). Untroubled by ambient humidity outdoors. Good airflow through an open-centre bush reduces mildew and leaf-spot risk; this cultivar already has useful mildew resistance. If you keep the room above 10 year-round and avoid placing the plant near a cold draught, a hot radiator, or an air-conditioning vent, you have already handled the two biggest indoor stressors.

Fertilising

Feed black redcurrant sparingly. Blackcurrants are nitrogen-hungry: apply a high-nitrogen feed or well-rotted manure in late winter, plus a balanced general fertiliser in spring. A potassium boost supports fruiting. Mulch annually with manure or compost, which feeds and conserves moisture. Avoid high potash/lime regimes meant for other fruit. Skip fertiliser entirely on a stressed, recently-repotted, or actively wilting plant — fertiliser salts make damage worse, not better. Wait for a round of healthy new growth before resuming a feeding rhythm.

Common problems

Below are the issues we see most often on black redcurrant in the Growli community. Each is annotated with the most common cause so you know where to start.

• Big bud mite — Mites swell dormant buds to round 'big buds' and can spread reversion virus. Pick off and destroy affected buds in winter; replace badly infected, virus-affected bushes with certified stock.
• Blackcurrant reversion virus — Spread by big bud mite; leaves become abnormal and yields collapse with no cure. Buy certified disease-free plants and remove affected bushes promptly.
• American gooseberry mildew — White powdery growth on shoots and fruit. 'Ben Lomond' has some resistance; improve airflow with open-centre pruning and avoid excess nitrogen-driven soft growth.
• Birds stripping ripe fruit — Birds quickly clear ripe currants. Net the bush as berries colour, or grow within a fruit cage.

Propagation

Very easy from hardwood cuttings: in autumn take pencil-thick prunings about 20-25 cm long, insert two-thirds deep in a sheltered trench, and they root over winter to transplant the following autumn. Always propagate from healthy, virus-free bushes. Propagation is the cheapest, most satisfying way to expand a collection — and it doubles as insurance against losing a mature plant to an accident. Take a backup cutting once the parent is established and healthy.

Toxicity to pets

Black Redcurrant is mildly toxic to pets. Blackcurrant (Ribes nigrum) is not individually listed in the ASPCA non-toxic or toxic plant database, so its status is treated as uncertain; handle with caution and verify with a vet. Note the wider grape/raisin (including dried 'Zante currant') concern is a separate, unrelated plant; true Ribes berries are generally considered low risk, but pet-safety is not ASPCA-confirmed. If you keep cats, dogs, or curious children in the house, weigh placement carefully — a high shelf or a hanging planter is enough for casual safety. For severe ingestion incidents, call your local vet and the ASPCA Animal Poison Control Center (in the US, 888-426-4435).

Pet-safety status is sourced from the ASPCA Toxic and Non-Toxic Plant List, which catalogues the most-asked-about plants for cats, dogs, and horses.

Black Redcurrant deep-dive guides

Every aspect of black redcurrant care, each with its own calibrated guide:

• Black Redcurrant watering schedule
• Black Redcurrant light requirements
• Best soil mix for black redcurrant
• Black Redcurrant fertilizing guide
• When to repot black redcurrant
• How to propagate black redcurrant
• Black Redcurrant growth rate & size
• Black Redcurrant cold hardiness
• Black Redcurrant temperature & humidity
• Is black redcurrant toxic to cats & dogs?
• Is black redcurrant toxic to cats?
• Is black redcurrant toxic to dogs?

Related guides

Black Redcurrant is also commonly called Ben Lomond blackcurrant.

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• All 3899 plant care guides in the Growli library