Cool, brisk days and chilly nights are indicators that winter is fast approaching, and irrigation systems need to be shut down. But a dormant irrigation system doesn’t mean your watering is complete.
As fall merges into winter, watering your new plants or existing evergreens will alleviate any moisture stress they may experience during winter.
What are new plants and when are they considered established?
Newly planted shrubs and trees take time to establish. Even under perfect growing conditions, shrubs will take two years before establishment. A 2-inch caliper tree can take three or more years.
This means that, even though the plant is doing well a year after planting, it’s technically not fully established. Until the plant is fully established, trees and shrubs are especially susceptible to drought, including dry winters.
Why do I need to water established plants in winter?
Despite the plants being dormant in winter, they still require water to survive. As long as the ground is not frozen, the roots will take up the moisture to survive the winter. If there is insufficient rain or snow during the winter months, additional water will need to be supplied.
Evergreens especially are susceptible to loss of moisture. Evergreens are prone to losing water through their foliage during the cold and windy winter months. This is known as transpiration. When this happens, the tips or entire needles or leaves will turn brown. Too much water loss through transpiration can cause the plant to die.
Broadleaf evergreens like Holly are especially prone to winter damage. Additional water helps to alleviate this damage.
How much should I water in winter?
A good, deep soaking will ensure the moisture is going to the root system. When the temperature is above 40 degrees, give a 5-gallon shrub approximately 5-gallons of water and a 2-inch caliper tree approximately 20-gallons.
If the winter is dry, you may have to water one to two times per month from November through March.
As the days get shorter and colder, working in the garden may become less appealing. But this one simple step will keep your plants healthy this winter and provide them with a renewed vigor in the spring.