Test soil around plants before watering
Soil should be only slightly moist before liberally applying water to any plant, whether in your garden or a container. Poke the probe of a moisture meter about 1″ deep around different parts of the pot to get an accurate sense of the moisture levels.

Water each plant
At the nursery, we water frequently in the summer heat. The correct procedure is to flood the containerized plant until the water runs slightly over the top sides of the container and drains out the bottom of the pot. If it drains quickly, then water it twice.

How often do I water?
You can become the best judge because you know the surroundings better than we do. Test the soil around the plant. Water thoroughly if needed. Check the soil moisture frequently and allow the plant to go slightly dry before watering thoroughly again. After 2 or 3 times of following this procedure, you will know the intervals of days the plant can go without watering again. On excessively hot days check plants two times!

Remember, if there is a drastic change of temperature; either way, it will affect your watering schedule.

Add water-holding polymer
Soil Moist to all your container plantings of flowers and shrubs. It will help cut your watering in half.