What causes the end of a tomato to turn and expanding dry gray?

Question

What causes the end of a tomato to turn and expanding dry gray?

Answer 1

This tomato affliction is called blossom end rot.  The good news is that blossom end rot does not spread from one plant to another, nor does it affect the plant itself and in most cases it is preventable.

Blossom end rot is typically seen early in the season and often doesn’t affect fruit that is set later in the summer.  The problem is caused by a poor supply of water and calcium in the developing tomatoes.  Tomato plants that were planted out in the garden before the soil warmed up are susceptible to blossom end rot because their root systems don’t develop well in cold soil.  Without a good root system the plants cannot take up enough moisture and calcium for the developing fruit, resulting in blossom end rot.  Blossom end rot may also be a problem after dry periods followed by heavy rains.

Mulching your tomato growing bed after the soil has warmed up is a good way to prevent blossom end rot as the mulch helps to maintain even moisture in the soil.  You’ll also want to keep the plants well watered during dry periods and avoid cultivating too closely to the plants as this can disturb tiny feeder roots that are close to the surface.  

If you have tomatoes afflicted with blossom end rot, just remove those fruits from the plant, maintain even moisture for your plants and wait for the next set of tomatoes to ripen.  

Answer 2

blossom end rot

Answer 3

You have blossom end rot which is a calcium deficiency usually brought on by inadequate or uneven watering.  The fruit is still ok to eat after you cut the rot off and the cure for the malady is to use chelated calcium, as per directions, obtained from your garden store.