Testing the soil moisture with a long screwdriver.

Use a soil probe or a long screwdriver to test soil moisture. Push the screwdriver into the soil about an hour after you’ve watered your plants. It will go easily into moist soil. Mark and measure how far it went into the ground. That will tell you how deep you have watered that plant. Every yard is different, but once you figure out how long it takes your watering system to water to certain depths, you’ll be set.