How often should tomato plants be watered?
Dear Gardener: I cannot tell you how often to water your plants as that depends on the soil, the humidity, natural rain and how much sun they are getting. They should be watered when the soil feels dry on top. Tomato plants don't need too much water once they are established. Overwatering can cause problems just as too little water will. Try to keep the soil evenly some what moist. A layer of mulch will help.