Checking Soil Moisture

Checking Soil Moisture

You don't have to have a soil moisture meter to determine if your soil is moist enough. Checking directly for both moisture and water penetration depth is a good practice for understanding how well your plants are watered.
  1. For trees or other landscaping, try pushing a soil probe or rod into the ground. When it stops going in, that shows how deeply water has penetrated. Irrigate until the water reaches 12 inches deep for grass, 12 to 18 inches for shrub and perennials, and 12 to 24 inches for trees.
  2. For garden beds or pots, use a trowel or simply stick your finger down into the soil a few inches to feel if it is moist or dry. Irrigate to keep the root zone moist. 
  3. For smaller pots, you can often tell by lifting them if they need water. Well-watered pots will be heavy. Watch out for pots that have become hydrophobic, where the water runs through them without getting absorbed. They will need to be watered very slowly or soaked in a larger container to get rehydrated. See our tips for dealing with hydrophobic soil.
Remember that plant roots need air as well as water, so you want your soil to be moist but not soggy. 

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