How to Water an Arborvitae

Arborvitae is an evergreen shrub, with some varieties hardy to USDA hardiness zone 2. It typically tolerates poor soil conditions but does require a planting location in partial or full sunlight. While arborvitae is generally easy to care for, during the first year after planting, it needs special attention to be sure the root ball does not dry out. Irreversible damage can occur if a newly planted arborvitae is not properly irrigated.

Water newly planted arborvitae thoroughly the first year. Set your hose next to the trunk, and let it trickle out so that it completely soaks the root ball, not just the soil around it. Leave the hose on for 20 to 30 minutes. Dig down, and feel the root ball. If it's wet, then you've watered it enough. If not, water it for another 20 or so minutes. Time how long it takes to get the root ball wet so you can estimate how long to leave the hose on next time.

Dig down a few inches to feel the soil during the first year. If it's dry, water your arborvitae so that, once again, the root ball is thoroughly moist. During the first summer, expect to water your arborvitae every three days. During the spring and fall, watering it once or twice a week will usually suffice. During that first winter, expect to water it once every few weeks, provided the soil is not frozen -- in which case, you can't water it.

Water an arborvitae that has been planted for a year or longer sparingly. Arborvitae generally needs little water once established; however, during an extremely hot summer or during droughts, water it with an inch of water to help protect it from the possibility of drying out.

Applying a 2- to 4-inch layer of mulch around an arborvitae will help conserve water.