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Bottom-of-Tomatoes-Turning-Black---THUMB.jpg

Bottom of Tomatoes Turning Black

My tomatoes are ripening but they are rotten on the bottom half. What can I do organically to correct this problem ? The plant is in a container (half whiskey barrel ) since we live in the desert and the soil here is not good.

The problem is blossom end rot. It is a common problem on tomatoes caused by a lack of calcium. But don’t rush out to buy a new fertilizer. Some soils do lack this essential nutrient but in most cases the deficiency results from a moisture imbalance. Usually just the first set of fruit, yes the ones we have waited for all year, are affected. The plants eventually adjust to their environment and the problem disappears.

You can cut off the black end and eat the ripe unblemished portion of the fruit.

Reduce the risk of blossom end rot with some minor adjustments in care. Stake and tower your tomatoes at the time of planting and avoid cultivation near the root zone. This reduces root damage that can lead to moisture stress and blossom end rot.

Water thoroughly and often enough to keep the soil evenly moist. Check your containers at least once a day and water whenever the top few inches are just slightly moist. Check more often if the pot is small or the weather is hot. Mulch both in-ground and container gardens to help keep the soil evenly moist.

I have not seen calcium deficiencies with most potting mixes. Many include slow release fertilizers while others allow you to add your own. Check the potting mix bag for details. If your potting mix doesn’t contain a season long slow release fertilizer you will need to do a bit of fertilizing. The frequent watering and fact the soil less mixes do not hold on to nutrients as long as our native soils means you will need to do a bit more fertilizing than when gardening in ground.

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