My ‘Black Krim’ tomatoes are cracking like crazy—vertically, horizontally, all over. Other tomatoes are fine. Please help!
As you have discovered, some varieties of tomatoes—often the ones with thin, tender skins—are more prone to cracking than others. In fact, genetics is the most significant factor leading to tomato “growth cracks.”
Weather is a frequent contributing factor. A heavy rainfall (or generous irrigation from the gardener) causes nearly ripe fruit to suddenly swell with moisture and the skin to split. Some experts say that too much nitrogen fertilizer is another cause. Fruits that are exposed to direct sun, rather than being shaded by the tomato foliage, may also be more likely to crack.
To limit cracking, strive to maintain steady soil moisture. Avoid high-nitrogen fertilizers. Keep foliage dry and clean and therefore better able to resist fungal diseases that lead to leaf loss. Harvest crack-prone varieties a day or two shy of maturity, especially if a heavy rain is forecast.
Despite your best efforts, you’re still likely to find a few cracked fruits. Just carve out the cracked parts and eat the rest. —Doug Hall