What is Blossom End Rot? If your tomatoes look black on the bottoms, they re probably suffering from blossom end rot. Blossom end rot can be identified by a black or dark discoloration, usually with a water-soaked appearance. It can also appear on peppers and eggplant. The good news is that it s not a disease, but rather the result of a calcium deficiency when the fruit was forming. Particularly in container gardening, the calcium deficiency that causes blossom end rot is often caused by inconsistent watering. If the soil gets too dry, the plant isn t getting the calcium it needs in order to produce healthy fruit. If the plant gets too much moisture, the same thing can happen. Blossom end rot can also be the result of over-fertilization during early fruiting. Blossom end rot sometimes occurs inP which have very consistent supplies of water and just the right amount of and dolomite, which should provide all the calcium the plants need. In an Earthbox, blossom end rot might be the result of unusually rapid growththe plant can t take in enough calcium quickly enough. The good news is that if you growing indeterminate tomatoes (that set fruit all season) and you have a few tomatoes with blossom end rot, it doesn t mean that all your tomatoes will be affected. Even without treatment, some of your later season tomatoes may be fine.
Don t plant tomatoes in cold soil, Don t over-fertilize, especially with high nitrogen fertilizer, Don t under-fertilize. Tomatoes are heavy feeders and potting soil, unless it is pre-fertilized, doesn t provide the nutrients tomatoes need. Use high-quality potting soil that drains well. Don t let your tomato plants dry out. Keep the soil moist, not wet Add dolomite or lime to potting soil when planting. Some people say that adding crushed egg shells and watering with diluted milk or yogurt can add calcium and prevent blossom end rot. If you experience blossom end rot in aP, mix 1/4 cup of lime with one gallon of water and pour it into the reservoir. Only do this once. This should fix the problem. Question: I am having a problem with some tomato plants in my back yard. The plants are growing good and strong and small green tomatoes are begging to grow. I looked at the bottom of one tomato and it is turning black. Can you please tell me what is causing this. There are several tomatoes on the vines of this plant, but only one tomato has this black section on it. George K. Answer: Hi George, Your black bottomed tomato sounds a lot like blossom end rot. I don t have a picture of it to post but a quick search will bring up countless photographic evidence for identification.
The reason I am ruling out other problems is because you describe your plants as healthy. Blossom end rot appears as a blackened, sunken spot on the bottom of green or ripening fruit. The plant itself rarely shows any signs of a problem. In fact some stricken fruit is found growing on plants that are exceptionally leafy and health. This particular brand of the condition is a symptom of excessively fertilizing with a high nitrogen fertilizer. In that case, much of the plant s energy goes into producing big, healthy leaves, leaving little else for fruit production. Blossom end rot is a very common condition said to be caused by a calcium deficiency, however in general the problem is not caused by a lack of calcium in the soil but inconsistent watering, drought, and uneven soil moisture making it difficult for the plant to draw nutrients up through the roots. From your description it sounds like your tomatoes are growing in-ground however this problem is especially common for container grown plants since containers dry out quickly and can be difficult to keep consistently watered. The good news is that the problem is easily fixed future tomatoes grown on the same plant aren t doomed to be diseased if you follow the advice below.
General Tips to Avoid Blossom End Rot Amend poor soil by adding lots of organic matter like compost. This will provide better nutrition for the plants and make for soil that holds moisture well. Water tomatoes deeply, but less frequently. This means give them A LOT of water when you do water rather than watering regularly but in small quantities. Water more often once your plants start to produce fruit, continuing to water deeply each time. Tomatoes are a watery fruit, your plant will need lots to grow healthy fruit. When Excessive Nitrogen is the Problem Cut back on high nitrogen fertilizers like fish emulsion. Add kelp meal or liquid seaweed to ergular waterings. You can even spray the blossoms with this mix when they first open. Tips for Container Gardeners When growing in a container, grow only one tomato plant per pot. Choose a container that is appropriately-sized for the plant. Small busing and dwarf tomato plants will do in a hanging basket but most tomatoes have very deep and ample roots requiring lots of space. Garbage bins are the way to go. Grow tomatoes in plastic pots when possible. Plastic retains water much better than terracotta, a difference that will become much more noticeable at the peak of summer drought.