Blossom end rot can ruin your tomatoes.  Nothing is more frustrating than to have a big, beautiful tomato that is just about ripe develop a rotting spot on the bottom, where the blossom was.  This is what blossom end rot does. It can take out half the tomato or stay a small speck, but the tomato is no longer so beautiful.

Not enough calcium.  The cause of blossom end rot is a lack of calcium in the plant.  Before you go dump calcium all over your tomatoes, you need to understand that it is more complicated than that.  The calcium may all ready be in the soil.  However, if there is too much of any of these compounds, it may effect the plants ability to draw the calcium into the plant and use it:  magnesium, potassium, sodium, or ammonium salts.

Don’t over fertilize.  Most tomato fertilizers have these compounds in them.  Early over fertilization can cause a problem because the tomato grows too fast, and needs more calcium to function than it can draw up, and because the fertilizer introduces too much of the suspect compounds into the soil.  Of course, over fertilization is never good.  It wastes money and risks burning the plant.

Watering mistakes. The second part of the equation is watering practices.  The tomato plant needs to get enough water, but not too much.  It is helpful to keep the water from getting on the fruit.  Drip irrigation or soaker hoses work well.  The plant does not need to dry out or start to wither between waterings, but it should not be wet, either.  In hot climates such as Texas, plants should be watered twice a week with one inch of water delivered each time.  If it rains, adjust the irrigation for that watering period accordingly.

Mulch, mulch, mulch.  One big help with keeping blossom end rot at bay is mulching.  Mulch around the plant both keeps the fruit off the ground and helps hold in moisture and release it gradually to the plant.  Staking or caging the tomato plant will help keep the fruit off the ground, too.

Root Causes.  The bottom line is that blossom end rot happens when the calcium uptake into the plant goes wonky and is made worse by watering problems.  Be careful how you fertilize and how you water and you should be able to keep blossom end rot at bay.

What other information would you like on tomato growing or gardening in general?  Please leave me a comment so I can provide the most useful content to my readers.

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