Watering Trees During Drought
Trees can and must be saved during the drought.
What you can do:
Deeply and slowly water mature trees 1 – 2 times per month with a simple soaker hose or drip system toward the edge of the tree canopy – NOT at the base of the tree. Water comes out of your full volume hose at about 10 gallons per minute while the most common drip emitter gives 1 gallon per hour per emitter. One rule of thumb is water 10 gallons per month per inch diameter of trunk at 4.5 foot height. Another simpler estimate is 100-150 gallons/month per tree. Use your irrigation clock or a Hose Faucet Timer (found at hardware stores) or hand held stop watch to prevent overwatering. Tree species and tree size matter so go to Canopy website that has charts to research tree needs.
Young trees need 5 gallons of water 2 times per week. Create a small watering basin with a berm of dirt. Another method is drill small holes in bottom of 5 gallon bucket, place near drip line of tree and fill with water which will drain slowly into the soil.
Shower with a bucket and use that water for your trees as long as it is free of non-biodegradable soaps or shampoos. You can also use the rinse water at the kitchen sink collected in 1 gallon basin.
Do not over-prune trees during drought. Too much pruning and drought both stress your trees.
Mulch, Mulch, MULCH! 4 – 6 inches of mulch helps retain moisture, reducing water needs and protecting your trees.
What else you can do to save water and your trees:
If you prefer, instead of soaker hoses or drip lines, you can put out several 5 gallon buckets with 5 holes drilled into the bottom of the buckets.
Set the buckets under the tree toward the edge of the canopy area and use a hose to fill with water.
This water will then seep slowly into the ground. The number of buckets will depend on your soil type as well as the size and species of tree.
Trees in sandy soils need to be watered more frequently than trees in clay soils.
Convert your spray irrigation system to a drip system so you do not have to depend on the manual hose timer. If you want help with converting your system, consult the manufacturer’s manuals and website for your irrigation system or talk to an irrigation specialist.
Remove the lawn or sheet mulch underneath your tree. Trees actually prefer wood chip mulch and the “duff” created by their own leaves. Learn how here.
Go to Saving Water page on California ReLeaf for more information.
Go to PDF Flyer on Saving Water, Saving Trees.
Spanish Version: Los Californianos Saben, Que La Conservación Del Agua, Es Para Toda La Vida.
More information:
Trees and Drought in California FAQ on California ReLeaf website.
Saving our Water and Trees on Palo Alto Canopy website.
Drought and Tree and Lawn Care on Davey Tree website.
Help your trees survive the drought flyer by Urban Forest Council.
