Next to soil, water is a vegetable garden's most important requirement. Under-watering your vegetable plants will retard their growth and reduce their yield. Over-watering may cause them to develop root rot or other fungal diseases. Make sure that the effort you made planning and planting your vegetable garden does not go to waste by consistently irrigating your vegetables with the right amount of water.
Check the soil frequently. Soil moisture is the best indication of your plants' water needs. Insert your finger or a wooden dowel into the soil to check the soil's moisture depth before you water. This will prevent you from over-watering. Check the soil moisture level of new transplants, seedlings and germinating seeds twice daily. Check mature plants' soil daily for most of the year; twice daily during the hottest months.
Apply water slowly and steadily so that water does not pool on the surface or run off. If it does, stop watering until it absorbs and then resume watering.
Use the gentle stream of a watering can to irrigate seeds and transplants. Water to keep the soil moist to a depth of 6 inches.
Use a a garden hose, soaker hose or sprinkler to irrigate established vegetable garden plants. Allow the top 1 to 2 inches of the soil to dry out before watering the soil until it is moist to a depth of 6 inches.