'Black Krim' Tomato (Black Krim Crimean tomato) care

Light

'Black Krim' Tomato needs sun on the leaves, not just bright ambient room light. Full sun, 6-8+ hours daily. Strong light and warmth deepen the characteristic dark shoulders; in dull conditions colour and flavour are muted. 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 krim' tomato crops want deeply 2-3 times per week; daily for containers in hot spells, keeping soil evenly moist. 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. Consistent watering reduces the cracking this large-fruited heirloom is prone to. Water at the base, mulch, and never let plants swing between bone-dry and saturated.

Soil and pot

'Black Krim' Tomato grows best in rich, deep, free-draining loam, ph 6.0-6.8. High organic matter supports the heavy beefsteak fruit. Work in plenty of compost and ensure drainage to prevent root rot under the big moisture demand. 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 Krim' Tomato sits happiest at around 40-70% humidity and 18-29°C (65-85°F). Adaptable outdoors. The large soft fruit and dense canopy make airflow important; humid, crowded plants are vulnerable to blight and botrytis. If you keep the room above 18 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 krim' tomato sparingly. Balanced feed at planting, then a high-potassium tomato feed every 7-14 days once fruit sets. The big trusses are hungry; steady feeding keeps fruit sizing without forcing soft, disease-prone growth. 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 krim' tomato in the Growli community. Each is annotated with the most common cause so you know where to start.

• Fruit cracking — Large, thin-skinned fruit splits at the shoulders after irregular watering or rain; water evenly, mulch, and harvest at first full colour.
• Green-shoulder / uneven ripening — Shoulders can stay hard and pale in heat; provide gentle afternoon shade in extreme sun and avoid heavy nitrogen feeding.
• Late blight — Dense foliage and damp weather invite spreading brown lesions; prune lower leaves, improve airflow, and water at the base.
• Blossom-end rot — Beefsteaks are especially prone to a leathery base from inconsistent moisture; keep watering steady and mulch rather than dosing calcium.

Propagation

Sow seed indoors 6-8 weeks before last frost at 18-24°C; harden off and plant out after frost. As an open-pollinated heirloom, saved seed comes true. Side-shoots root easily in water or moist compost. 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 Krim' Tomato is toxic to pets. As a Solanum lycopersicum cultivar, the tomato plant is ASPCA-listed as toxic to cats, dogs, and horses. Solanine and tomatine in the foliage, stems, and unripe green fruit are the toxic principles; the ripe dark fruit is non-toxic. Ingesting green parts can cause hypersalivation, inappetence, GI upset, weakness, dilated pupils, and slow heart rate. 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 Krim' Tomato deep-dive guides

Every aspect of 'black krim' tomato care, each with its own calibrated guide:

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

Related guides

'Black Krim' Tomato is also commonly called Black Krim Crimean tomato.

• Tomato care — light, water and common problems
• Pepper care — light, water and common problems
• Cucumber care — light, water and common problems
• All 1284 plant care guides in the Growli library