How to Grow and Care for Black Krim Tomato

Black Krim are medium-size heirloom tomatoes in a color range from dark maroon to deep purple or almost black. It’s not only the color but also the squat, flattened globe and taste that make this tomato variety stand out. Black Krim tomatoes have an intense flavor with sweet and acid notes; their taste is often described as slightly salty. The tomatoes are named for the Crimean peninsula on the Black Sea (“Krim” in Ukrainian) where they originated.

All parts of the tomato plant except for the fruit are toxic to humans and pets.

How to Plant Black Krim Tomato 

When to Plant

Black Krim are highly sensitive to cold. Plant after danger of late spring frost, and the soil temperature has reached at least 60 degrees Fahrenheit. Harden the seedlings off before transplanting them in the garden.

Selecting a Planting Site

Sun is essential even more so for Black Krim which need lots of sunlight and heat to achieve full color. Before planting check the surrounding area for plants that could cast shade on the tomatoes. Choose a spot with excellent drainage.

If you don’t have a suitable location in the ground, you can grow Black Krim in large containers. 

Spacing, Depth, and Support

Black Krim tomatoes are indeterminate and need ample space and a sturdy support, such as staking or tomato cages. Leave 3 to 5 feet between the plants in each direction, the more space, the better to allow air flow and give you easier access when picking. Depending on the size of the seedling, you can plant using the deep hole method where you bury up to one-third of the plant, or the trench method where you lay the seedling on its side. 

Black Krim Tomato Care

Light

Black Krim tomatoes need at least six to eight hours of full sunlight per day.

Soil

Soil should be loamy, rich and well-drained, with plenty of organic matter. Tomatoes do best with a slightly acidic pH (6.0 to 6.8).  

Water

Water deeply and regularly and never let the soil dry out. During hot summer weather, and for tomatoes growing in containers, this means daily watering, if not twice daily during a heat wave. Dry soil during fruit development can cause blossom end rot.

The watering technique is also important. Water at the base of the plant and avoid overhead watering which can lead to the spread of diseases such as blight. 

Temperature and Humidity

Black Krim are tolerant of heat but not cold so time your spring planting to the weather. High humidity can promote fungal diseases when the dense foliage stays wet. This can be prevented by pruning to provide good air circulation and by generous spacing between plants.

Fertilizer

Use a general slow-release organic fertilizer for vegetables, or a special tomato fertilizer slightly higher in potassium. Calcium helps prevent blossom end rot. For exact amounts, follow the label instructions. Mix the required amount into the soil when planting; then, after the plant is established, fertilize every 2 to 3 weeks from May through August. Make sure to spread the fertilizer at least 3 inches away from the stem and water it in well each time. The same applies to container-grown tomatoes. 

Pollination

Tomatoes are mostly self-pollinating, so you don’t need to rely on pollinating insects. Because Black Krim are open-pollinated, there is a chance they could cross-pollinate with other tomato varieties nearby. This is nothing to be concerned about for the current growing season; the tomatoes from the plant will be the expected Black Krim variety. However, if you plan on collecting the seeds for next year’s crop, the fruit could be a genetic mix of two varieties. To avoid cross-pollination, plant different heirloom varieties at least at 10 feet apart. 

Harvesting Black Krim Tomato

Determining when Black Krim tomatoes are ready for harvest can be a bit tricky because the shoulders (the area around the stem) remain olive-green or remain tinted green even when the tomatoes are ripe. Disregard the shoulders and look for fruit otherwise dark, brown-red to black, with smooth and waxy skin.

How to Grow Black Krim Tomato in Pots

Choose at least a 10 gallon pot heavy enough to keep the plant and its support from toppling over. Make sure the pot has large drainage holes and fill it with high-quality, nutrient-rich potting soil.

Pruning

Pruning is necessary to keeping the lush growth of indeterminate Black Krim tomato plants under control. It also improves air circulation.

Early in the season, remove all the suckers and low branches that touch the ground. (To prevent long branches from touching the ground, stake your tomato plants.) Later in the season, move from pruning out suckers to thinning out leaves to increase airflow. About one month before the average date of the first fall frost in your area, you can also cut the top off the plants, and remove any new flower clusters and tiny tomatoes that won’t reach maturity anyway. That way the plant’s energy goes into ripening the last tomatoes rather than producing more foliage and flowers. 

How to Grow Black Krim Tomato From Seed

Starting Black Krim tomatoes from seed is not difficult—it's similar to growing any other tomato from seed. If your local nursery does not carry Black Krim seedlings, starting them from seed is often the only way to get your hands on this heirloom variety.

Common Pests & Plant Diseases 

Black Krim tomatoes are prone to cracking and blossom end rot, which is often caused by irregular watering practice. The plants are also susceptible to fungal diseases, like Fusarium wilt, and Verticullium wilt.