Tomato help! (Blossom End Rot)


Old 07-17-05, 12:08 PM
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Tomato help! (Blossom End Rot)

I have a tomato plant (indeterminate) is in a very large pot on my deck - Good sun. It is about 36" high and looks healthy. My fruits develop a rot (tan proceeding to black) on the bottom and I have to pick and toss.

We have had a series of warm days (90+) and warm nights (72) for the past week, which is unusual for Minneapolis. Prior to that, we had a more or less normal summer. This started before the heat wave, but has continued through it. I try to error on the side of underwatering since it is too easy to over-water because of the convenience.

The soil in the pot is fresh (this year) - potting soil. Fertilizing lightly.

I do not remember the variety, but I usullay try to pick a disease and fungus resistant variety.

Any thoughts or do I just pull it and throw?

Old 07-17-05, 12:37 PM
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end rot on tomatoes

the tomatoes is in need of some calcium,you can get this at your garden center , i always mix lime in with my garden soil when i plant them , but since you have them in pots, i would get the small botte and mix with water .also tomatoes need water, letting go dry can cause that to, because even with calcinm in the soil, the tomatoes cannot take it up with out with even watering and some calcinm should help with the next tomatoes that bear on the vine...hope this helps you , dennis
Old 07-17-05, 01:00 PM
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tricks for keeping the soil moist: peat moss, black plastic. Frequent watering is very difficult in hot weather in full sun. Tomatoes are difficult to keep in pots for this reason alone: not enough water. You need to water very regularly, like when you leave the house in the morning and again in the afternoon. Good luck

fyi the situation you have is called 'blossom end rot'
Old 07-17-05, 01:42 PM
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Blossom-end rot is a result of conditions where demand for calcium exceeds supply. This may result from low calcium levels, or ions in soil that compete with calcium ions, drought stress, or excessive soil moisture fluctuations which reduce uptake and movement of calcium into the plant, or rapid, vegetative growth due to excessive nitrogen fertilization. Thus, the explanation is not simply explained by low calcium in soil, but it can also be caused by environmental conditions that may affect the plant's ability to remove calcium from soil.

A soil test should be done to determine what amendments need to made to soil, if any. 6.5 is the recommended pH for tomatoes. A good way to increase calcium ions in soil is to add lime. Nitrate fertilizer is recommended, not ammoniacal nitrogen that tends to promote blosson-end rot because the ammonia reduces calcium intake. Avoid fertilizing during early fruiting. Use mulch to conserve moisture and use irrigation if plants are not getting one inch of rain per week.

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