how do u prevent black rotten spots on tomatoes when ripening?
Answers:
What you have sounds like blossom end rot which is caused by a calcium deficit. The following info is cut and pasted from hgic.clemson.edu info sheet number #1323
Blossom-end rot can be a serious problem with tomatoes. The main symptom is a dark-colored dry rot of the blossom ends of the fruit. It occurs when there are extremes in soil moisture, which cause calcium deficiency in the fruit. When rain or irrigation follows a dry spell, the roots cannot take up calcium fast enough to keep up with the rapid fruit growth. Blossom-end rot also occurs if the delicate feeder roots are damaged during transplanting or by deep cultivation near the plants.
The following measures will help prevent blossom-end rot:
Test the soil and maintain a pH between 6 and 6.5 and an adequate calcium level by liming or applying gypsum.
Mulch with 2 to 3 inches of materials such as grass clippings, pine straw and leaves. Mulching prevents rapid soil drying and allows roots to take up available calcium efficiently.
Do not overfertilize plants with nitrogen or potash. Excessive amounts of these nutrients depress the uptake of calcium.
Keep moisture levels fairly uniform by regular watering and by maintaining a mulch layer around the base of the plants. Water plants during extended dry periods. Tomatoes need 1 to 1 ½ inches of water per week.
Add organic matter to the soil. This will help "loosen" clay soils and will improve the water-holding capacity of sandy soils. In either soil, organic matter will increase plant uptake of water and calcium.
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There is also a spray for blossom end rot you should be able to find at a garden center or a box store's garden area. Just tell them your tomatoes have blossom end rot and you need spray to fix it.
Good luck
Other answers:
do you let the plants dry out..?that can cause black spot...and to wet also..use a good tomato feed...this will also help
do you let the plants dry out..?that can cause black spot...and to wet also..use a good tomato feed...this will also help
I think it is from them touching and being to wet cut back on the water that goes on the plants water on the ground.
sounds like you have blossom end rot..a nutrional disorder.they are growing so fast they can't get enough calcium .Put dried eggs shells around them also when you plant use a heaping shovel full of compost,1 tsp. gypsum,1 tsp. Epsom salts , mix this in a bucket when you plant your seedlings add a shovel full in the hole..
Black spots are most commonly cause by a calcium deficiency. Visit you're local Greenhouse/Garden Center and ask for a Calcium fertilizer/supplement for tomatoes. They should carry it.