Water is the single biggest factor in whether a young tree makes it through its first few Virginia summers.
Too little and roots dry out. Too much, especially in clay, and roots suffocate and rot. The goal is deep, occasional watering that soaks the root zone and then lets it dry slightly.
Newly Planted Trees
- First few months: Water two to three times a week. The Virginia Department of Forestry suggests roughly 2 to 3 gallons per inch of trunk diameter each time.
- Rest of the first two years: Water deeply once a week when there hasn't been about an inch of rain.
- Where to water: Right over the root ball, then a little beyond it as roots spread.
- How: A hose on a slow trickle for 20 to 30 minutes, a soaker hose or a slow-release watering bag all work well.
Larger trees take longer to establish. A rough rule is one year of care for every inch of trunk diameter at planting.
Established Trees
Mature native trees usually handle normal Virginia weather on their own. During a drought, generally two weeks or more of summer heat without real rain, they benefit from help.
- Water slowly across the area under the canopy and beyond, not just at the trunk. The roots that take up water are spread out and near the surface.
- A common rule of thumb is about 10 gallons per inch of trunk diameter, applied every week or two during a drought.
- Water early in the morning so less is lost to evaporation.
- Prioritize young trees, recently disturbed trees and shallow-rooted species like river birch, red maple, dogwood and beech.
How to Check the Soil
Push a long screwdriver or your finger 4 to 6 inches into the soil near the root ball. If it's dry at that depth, water. If it's still damp, wait. This simple check prevents both underwatering and overwatering.
Signs of Drought Stress
- Leaves wilting in the afternoon and not recovering overnight
- Brown, crispy leaf edges
- Early yellowing and leaf drop in mid-summer, common on tulip poplar and river birch
- Thin canopy and small leaves the following year
Signs of Overwatering
- Yellowing leaves while the soil stays soggy
- Wilting even though the ground is wet
- Soft, dark or peeling bark at the base of the trunk
- Mushrooms growing at the base
Lawn irrigation is a common culprit. Sprinklers that run for a few minutes every day keep the surface wet but never soak deep, and heads that spray the trunk every day invite rot. Adjust heads away from trunks and water less often for longer.
Don't Forget Fall and Winter
Dry falls are common in Virginia. A deep watering in October or November, before the ground cools, helps trees go into winter with moist roots. Evergreens like American holly, red cedar, pines and sweetbay magnolia keep losing water through their leaves all winter. Give them a drink during long dry spells when the ground isn't frozen.