This is what Magnesium deficiency in tomatoes looks like. If your tomato looks like this, then adding Epsom salts will help solve this problem.Try adding 1-2 tablespoons per gallon of water and water plants lightly with it *after* regular watering.
If it doesn’t look like this, you’re wasting your time with Epsom salts (it doesn’t do anything else or help any other problems such as blossom end rot)
But it’s one of the worst Internet myths. So let me repeat – do not add Magnesium (Epsom Salts) to your garden for any reason unless your tomato plants look like this. If they don’t – then don’t add. Can I be any clearer on this?