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How to Feed Calcium to a Tomato Plant

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Tomato plants require much more calcium than other fruits and vegetables. Soil that is not already rich in calcium will allow disease such as blossom end rot to infect your tomato plants. Perform a soil test to discover if your soil is deficient in calcium. Eggshells contain 95 percent calcium carbonate making them an ideal calcium additive.

Place your collected eggshells in a blender and blend until you have a dry powder.

Sprinkle the powdered eggshells into the bottom of your planting hole. Plant your tomatoes as you normally would.

Wait until your tomato plants begin to grow. Blend more eggshells into a powder.

Sprinkle the powder around the tomato plant. Use a hand trowel to mix the eggshell powder into the soil. Repeat every two weeks during the growing season.

Calcium Nitrate Per Tomato Plant?

Tomato plants require a balanced dose of nitrogen, phosphorus and calcium, but over-fertilizing and poor soil quality can cause imbalances. Amend your soil periodically with lime to increase pH and provide calcium. If your tomatoes have already developed blossom-end rot, you can provide more balanced nutrition using a foliar spray of calcium nitrate mixed with water. Mix the side dressing carefully into the first 1 inch of surface soil and avoid getting it on the leaves.


Save the water you use to boil your eggs with. Water your tomato plants with it.


If your soil test comes back with a normal calcium reading, there is no need to feed your tomato plant calcium, although it won't hurt the plant.

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