How to tell if plants have enough water.
Make a small hole 5"to 6" deep in flower or vegetable bed.
If soil at bottom is moist you know your ground is well watered.If you have wilted plants and the ground is well watered look for other problems (bugs, disease etc.)
Some Hints on Watering Plants
If possible water in AM to lose less water from evaporation and hydrate (Water) roots for heat of day.
Water slowly and throughly about once a week. A soaker hose does well as does a water jug or a large can with small holes near the bottom and set close to plants and filled as conditions warrent,every day to once a week. Or water with a regular hose and spray nozzle.
Mulching helps to retain water.