Eggshells generally decompose quite slowly, so we think of them more as something to add to compost. It’s more of a myth that crushed eggshells will prevent blossom end rot in tomatoes. This kind of calcium deficiency is not a result of inadequate calcium in the soil, but rather the ability of water to take up the calcium. The good news is that they won’t harm your soil or plants and they do add organic material for soil organisms.
If you’re ever worried about calcium in the soil, it’s best to do a soil test which is usually free or very low-cost through your cooperative extension. Agricultural lime and gypsum are good sources of calcium if your soil test says you need calcium.
Eggshells generally decompose quite slowly, so we think of them more as something to add to compost. It’s more of a myth that crushed eggshells will prevent blossom end rot in tomatoes. This kind of calcium deficiency is not a result of inadequate calcium in the soil, but rather the ability of water to take up the calcium. The good news is that they won’t harm your soil or plants and they do add organic material for soil organisms.
If you’re ever worried about calcium in the soil, it’s best to do a soil test which is usually free or very low-cost through your cooperative extension. Agricultural lime and gypsum are good sources of calcium if your soil test says you need calcium.