While trees work hard to keep us cool, they need protection from the hot sun too.
Dry conditions and high temperatures leave trees feeling parched. Well-hydrated trees cope better with the heat. But how much water do mature trees need? And when is the right time to water them? It depends. Grow your tree watering knowledge with the following information.
Signs it’s time to water trees
There are obvious signs trees need water, but sometimes there's uncertainty about the right amount of water needed to keep trees healthy. The soil holds the answer.
Use a shovel to dig down about 6 to 8 inches and pick up a handful of the soil. It should be cool to the touch and slightly wet, but not soaking. If the soil is really wet, that's a sign of overwatering.
If you don’t have sandy soil, roll the soil into a ball. If it doesn’t hold its shape, the soil is too dry, and it’s time to water.
Proper tree watering
To ensure you’re giving trees the right amount of water, look at your tree’s “drip zone,” the area directly beneath the foliage. Water needs to saturate the entire drip zone and roots of your tree. Most trees are sufficiently hydrated if the upper 12 inches of soil around the roots are soaked at least once per week. Generally, trees should receive five gallons of water for every inch of trunk diameter.
Water trees once a week from March until October, and twice a week during periods of little or no rain.
Tree watering methods
Use rain barrels and reclaimed water in the garden whenever possible. Rain barrels collect runoff from your home's gutter system by connecting to the downspout. Add a spigot or hose connector to drain water, and use the water to refresh your landscape.
Soak the ground
Deeply and slowly water mature trees one to two times per month with a simple soaker hose or drip system. Rather than watering at the base of the tree, soak the ground toward the edge of the tree canopy. Use a hose faucet timer, available at most hardware stores, to prevent overwatering.
Use a tree watering bag
Choose a reusable irrigation bag for new or sidewalk trees with shallow roots. Fill it up once or twice a week, and it will deep water for you.
To make sure you’re not overwatering, place an empty soup can near the tree inside the sprinkler pattern, and run the sprinkler very slowly for several hours until 2 to 3 inches of water have collected in the can.
For the finishing touch and to conserve water, add mulch. Spread mulch in a wide circle, no more than 3 inches deep around the tree. Mulch should be pulled back from the trunk of the tree like a donut, not like a volcano. Recommended mulches include wood chips, shredded leaves, pine needles and compost.