Watering Your Trees and Shrubs

Now that summer is in full swing, watering your trees properly is one of the best ways to keep them healthy and stress-free. But did you know — the most common watering mistake is actually too much water?

Whether it’s too much or too little, watering can be tricky if you don’t know how to do it. Follow this guide to ensure your trees make through summer with flying colors:

When to Water

During a summer afternoon, up to half of the water can be lost to evaporation. The best time to water is in the morning or evening, so the roots have a chance to absorb most of the water.

Unfortunately, there’s no magic schedule for watering trees. How often you should water will depend on the size of your tree, soil conditions, and weather conditions. Newly planted trees require much more water than established ones.

The best way to determine when trees need water is to check the soil. What you’re aiming for is moist — not soggy — soil. In the absence of rain or moisture, check the soil with a garden trowel to a depth of two inches. If the soil is dry to the touch, your tree needs water.

How Much

Newly planted trees need ten gallons per inch of trunk diameter per week, spread out over several long, deep waterings. The rule of thumb is that it takes roots one year to establish for every inch of trunk diameter, so we’re talking about three years of supplemental watering for a tree with a trunk three inches in diameter.

But what about established plants that are just going through a dry spell? When in dry conditions, remember that trees and shrubs need less frequent—but deeper—watering. Established plants that are drought- sensitive will tell you they need water when they are wilted or droopy.

With increasing weather fluctuations bringing more wet and dry spells, you’ll have to be vigilant. If the weather is hot, sunny, windy, and dry—averaging less than half an inch of rain per week for a couple of weeks—your lawn and newly planted trees or shrubs will quickly forget all about that wet spring.

Mulch is Your Best Friend

Proper mulching is a highly effective way to keep the soil from drying out quickly, especially during excessive heat. Applying mulch 2-4 inches deep will help conserve moisture and regulate the soil temperature.