Tomatoes going black

Question

all my greenhouse tomato plants,the fruit on them are all developing black bottoms ??

can any one explain the cause ?

too little or too much water ????

Answer 1

Blossom End Rot is a calcium deficiency caused not so much by overwatering, but by uneven watering (Letting the tomatoes stay way dry during hot summer time and then giving in and watering the garden, then letting them dry again.). To prevent BER, mulch under plants, water moderately when the weather is dry and hot. Don't go through the wet/dry cycle to any extreme and you should have the problem licked. I always pick and pitch any young tomatoes which have begun BER as soon as I see them, as they cause the plant to waste lots of energy and nutrients bringing them to maturity. They'll likely be stunted and marred fruits anyway.

Answer 2

This happens to mine when I water the leaves excessively and not the soil.

Answer 3

It might be blossom end rot. This is a problem caused by too little calcium in the growing medium (soil or other sources).

If you are talking about black spots all over the fruits, it might be blight; this isn't a watering problem, it's a fungus. You'll need to pull up all the plants and destroy them, and next season, you should not plant tomatoes in the same spot.  

It's hard to say because you haven't offered enough information. Are the black-bottomed fruits green or ripe? Are the spots only at the blossom end or other places? Are there other problems? How much have you watered and when?

Answer 4

By the sounds of things, you are overwatering the plant. Though, i've never heard of a plant turning black to to overwatering. Must have been some opportunistic fungus that infected the plant due to the fact that it was stressed from being overwatered.