How to Make a Calcium Spray for Tomatoes

Otherwise healthy-looking tomatoes can produce fruits with dark, discolored bottoms. The culprit is blossom-end rot, a physiological condition that causes the blossom end of the fruit to blacken and shrivel soon after the tomato begins to form. Causes include drought or dry soil conditions during fruit formation or a calcium deficiency. Proper irrigation practices eliminate drought concerns, while supplying the tomatoes with sufficient calcium via a spray application prevents most other blossom-end rot problems.

Things You'll Need

• Calcium nitrate
• Spray bottle

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Instructions

1. • 1

     Dissolve 4 tablespoons of granular calcium nitrate in 1 gallon of water. Calcium nitrate is available at garden centers.

   • 2

     Place the mixture into a clean garden sprayer or spray bottle. Label the bottle with the contents.

   • 3

     Spray the tomato plants with the mixture once they begin sending out the second set of blossoms. Coat the foliage on the plant with an even spray, making an application every two or three days until the fruits begin to form.