Most homeowners don’t think about watering their trees and shrubs in the winter. But at Custom Lawn & Landscape, our tree and shrub care team knows watering is critical during the winter for plant health. Yes, plants and shrubs get some water from rain and/or melting snow, but they need more than nature provides. Root damage can occur if trees and shrubs aren’t watered enough in the winter. This affects the overall health of the tree. Evergreens especially need watering because they retain their needles all year round. Fluctuating temperatures, dry air, windy conditions, intense winter sun all contribute to tree and shrub dessication. By late winter, if they haven’t received enough water, they can transpire. They become very dry and brittle. If they suffer too much, the needles can turn red or brown from sun scorch. Sun scorch usually occurs on the west and south side of the trees where the trees are subject to intense winter sun. To prevent desiccation or even sun scorch, make sure these trees and shrubs get watered. Custom Lawn has assembled a Winter Water Guide below with handy tips on how to water, how often, and how much. Feel free to print this guide out and tack it to your refrigerator as a handy reminder.
Custom Lawn’s Winter Watering Guide
- Water only when air and soil temperatures are above 40 degrees Fahrenheit and there is no snow on the ground. If you water when it’s too cold, the water will freeze on the surface and can cause suffocation of the grass below if there for a month of more.
- The roots of large trees have a root spread equal to the height of the tree, (or two times the diameter of the tree) so apply water to the entire area within the dripline and around the base.
- Apply water at mid-day so it will have time to soak in before the temperature drops at night and possibly freezes the soil.
- Don’t forget to water in March and April when new roots are forming.
- Mulch your plants to help them retain water.
- Newly planted shrubs require more water than established plants (at least one year old).
- Pay special attention to evergreens because they keep their needles all winter.
- Pay special attention to trees and shrubs on west and south sides of your home. These trees are victims of intense winter sun and can experience sun scorch if not watered enough.
- Trees obtain water best when it is allowed to soak into the soil slowly to a depth of 12 inches.
- Sprinklers, deep-root fork or needle, soaker hose or soft spray wands are all acceptable methods for watering. If using a deep-root fork or needle, insert no deeper than 8 inches into the soil.
- A good rule of thumb is to apply 10 gallons of water for each inch the tree is in diameter. For example, a two-inch diameter tree needs 20 gallons per watering.
How Much Water Is Enough?
In the winter, all shrubs benefit from watering from October through March.
New shrubs – apply 5 gallons two times per month.
Small (3 feet or smaller) established shrubs – apply 5 gallons every month.
Large (6 feet or taller) established shrubs – apply 18 gallons every month.
Decrease amounts if it has rained recently.
Remember to Water
The tricky thing about winter watering is that the plants usually look fine (excluding sun scorch), but the damage isn’t obvious until the next summer. The injury is to the root system, so affected plants may appear fine and probably will even resume normal growth patterns in the early spring. But plants whose root system was damaged will die in late spring or early summer when temperature rise and the plant is under stress. Additionally, weakened plants are also more susceptible to insects and diseases. Remember to water those trees and shrubs this winter and they will reward you with healthier growth and bigger blooms this summer!