A Guide to
Tree Care in
Dry Climates
English/Español

Tips
on Tree
Watering
from Denver Water and
the Community Tree Alliance

Tree roots are not like carrots.

Tree root systems can spread two to three times wider than the height of the tree. Most of the tree's absorbing roots are in the top twelve inches of the soil. Water should be applied within the dripline (the critical root zone shown below).

The boxed area is the dripline, or critical root zone.

For xeriscape and conservation information, visit: www.denverwater.org. For more details on watering and tree care, visit: saver.denverwater.org. Para recibir la información en español, sobre el cuidado de árboles, llame al 303-893-2444. Visit saver.denverwater.org for suggestions on care of your trees and shrubs in our dry climate. The web site offers tips from tree care professionals on the following subjects: General tree watering recommendations Tree watering devices Caring for trees Planting trees and shrubs Shrub watering recommendations These recommendations were prepared by the Community Tree Alliance, which is comprised of tree professionals from the following: Cities: Arvada, Aurora, Boulder, Broomfield, Denver, Ft. Collins, Greenwood Village, Lakewood, Littleton, Louisville, Town of Castle Rock, Westminster, Wheat Ridge Other Government: CSU Cooperative Extension, Denver County, Jefferson County, Colorado State Forest Service, Denver Water, South Suburban Parks District Not-for-Profit Organizations: Colorado Tree Coalition, Green Industries of Colorado, The Park People

Water deeply and slowly.

Apply water so it moistens the soil in the critical root zone to a depth of 12 inches. Methods for watering include a deep root fork or needle, soaker hose or soft spray wand. Apply water to many locations under dripline. If a deep root fork or needle is used, insert the device no deeper than eight inches into the soil.

When should I water?

Trees in regularly watered turf areas should not need supplemental water. When watering restrictions prohibit turf watering or trees are not in turf areas: water small trees 4 times per month, medium trees 3 times per month and large trees 2 times per month.

How much water should I apply?

The amount of water is based on tree size (trunk diameter) and monthly frequency. Use a ruler to measure your tree's diameter and then refer to the enclosed schedule.

Mulch helps retain soil moisture.

Mulch is critical to conserve soil moisture. Apply organic mulch within the dripline, at a depth of four inches. It's best to eliminate turf prior to adding mulch. Leave a six-inch space between the mulch and trunk of trees. Mulch materials may include wood chips, bark, leaves and evergreen needles.

Moisture is needed to avoid disease.

Stressed trees are more vulnerable to disease and insect infestations and branch dieback. Keep a watchful eye for anything that looks out of the ordinary.

April – September Tree Watering Schedule (Minimum Water Requirements)
		Small Trees			Medium Trees			Large Trees
Trunk   Diameter (inches)		Weekly 10 gal/"diameter			3x/Month 10 gal/"diameter			2x/Month 15 gal/"diameter
		<1"	1"	2"	4"	6"	8"	10"	12"	14"+
	Watering Device
	Deep root fork 2 gal/min	5	10	15	20	30	40	75	90	105
		Minutes
	Deep root needle 2 gal/min	5	10	15	20	30	40	75	90	105
		Minutes
	Soft spray wand 4 gal/min	3	5	8	10	15	20	38	45	53
		Minutes
	Soaker hose 2 gal/min	5	10	15	20	30	40	75	90	105