Recognise blossom end rot

3rd August 2022

Blossom end rot is a disorder that often affects the first tomatoes to ripen - a patch of skin farthest from the stalk fails to develop properly and becomes dark and leathery, making the fruit inedible. It is a problem with calcium levels in the plant, which can be caused by irregular watering or by over-enthusiastic use of tomato feed, which is largely potassium and prevents the uptake of enough calcium to form all the cells the swelling fruit needs. Usually only the first few fruits show this and the problem clears up with the rest of the crop.