Is salt bad for tomato plants?

Some salt is healthy. Too much is deadly. Your best bet is to buy a bag of epsom salt and read the lable. I add about 1 tablespoon of epsom salts to the area around the base of every tomato plant. It has magnesium in it and is beneficial for cellular production and growth, the salt is beneficial to the water carrying abilities and aids in osmosis, or the water distribution in the plant. I also add 1/4 cup of lime and about 8-10 cups of composted cow manure to the base of each plant after planting. This way, every time you give the plant water, you give a dose of fertilizer, a dose of calcium from the lime to prevent bloom rot and salt and magnesium. I dont use miracle grow, because its too high in nitrogen and can stunt fruit production.