How to Correct Soil With Low Calcium

Dig a hole in your garden 1 foot deep. Collect a soil sample from the side of the hole and put it into a small plastic cup. Test your soil sample according to the directions on the packaging for your kit. A calcium reading lower than 1,000 parts per million, or PPM, is considered deficient, while a low number --- below 7.0 --- for your pH results signals acidic soil.

Disperse an even quantity of gypsum over the entire garden bed if the calcium is low, but your pH levels are appropriate to the plants you're growing. Apply 1 to 2 pounds of gypsum for every 100 square feet of soil you need to cover.

Spread an even coverage of pelletized limestone over the soil if the calcium and pH were low, as the lime can aid in raising both. Use no more than 5 pounds of limestone for every 100 square feet of garden space.

Treat small gardens organically by crushing up eggshells by hand or with a coffee grinder. Sprinkle a cup of eggshells over the garden for every square foot of soil space, and work them into the upper inch of soil, using a cultivator.

Repeat Step 1 to test the soil again after a month and note how the calcium levels have changed. If the calcium still needs to be raised, then repeat your preferred method from Steps 2, 3 or 4, and test again in another month.