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Old 26-08-2010, 03:06 PM
Granity Granity is offline
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First recorded activity by GardenBanter: Jul 2006
Location: Bedfordshire
Posts: 444
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Quote:
Originally Posted by Ed View Post
My tomatoes are coming on fine.. Except that the base/bottom of them are
black.

What kind of infestation is that? What has caused it?

Ed
It's in fact caused by a calcium deficiency, This may result from low calcium levels or high amounts of competitive cations in the soil, excessive soil moisture fluctuations which reduce uptake and movement of calcium into the plant, or rapid, vegetative growth due to excessive nitrogen fertilization.