Calcium Nitrate is a water soluble form of Calcium (Ca) that you can make a spray with and spray on your plants to get them calcium, to help stop or prevent blossom end-rot. You should always make sure your soil has lime/calcium, but additional spraying can give your tomatoes the Ca they need if Blossom End-Rot appears.
Always test spray your plants before covering a plant with any new spray.
Wait 48 hours after testing a few leaves and if there is no damage, spray the plant.
A general recipe is 1 tablespoon of calcium nitrate per gallon of water
or 1 teaspoon per quart of water.
Good Luck with Your Garden,
Gary (The Rusted Garden)
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