It’s January and the local weather forecasters are warning us about winter weather approaching in the days to come.
What does winter weather mean for your lawn and landscape?
For young trees and trees with thin bark, wrapping the trunk in the winter will protect the tree from damage due to freezing and thawing temperatures.
If you have perennials or winter annuals such as pansies or kale, winter moisture is critical to their performance going into the spring.
Fescue lawns will retain more color in the winter and rebound quicker in the spring if they are not allowed to become bone dry during the winter.
Newly sodded lawns, due to a shallow root system, can experience freeze damage if the roots are dry during a winter cold spell.
Finally, all newer landscapes, those installed in the last two years require a little more watering attention over the winter.
The goal is to make sure the top few inches of soil is moist well ahead of freezing temperatures. Roots are still active and providing moisture for the plant. Once the soil freezes, the roots no longer have the ability to replace moisture lost to transpiration.
Our rule of thumb is to keep your irrigation operational through the winter, monitor the weather, and be ready to water once every 7-14 days if we have not received a good rainfall.
Biggest Winter Issue – Lack of moisture
Lack of adequate soil moisture is often a major cause of winter damage. All lawns, shrubs, trees, perennials, and annuals need moisture during the winter. This is particularly true about evergreens. Remember, your lawn and landscape are dormant, not dead, and moisture is still important.
Most winter plant injury occurs when we receive a harsh cold spell while plant root systems are dry.
Winter watering is particularly critical for evergreen shrubs and trees. Windy days zap the moisture stored in their leaves making them sensitive to winter injury when we receive a harsh cold snap when they are dry.
Windy and cold winter temperatures dry needle and evergreen plants foliage. It is important they have moist soil for the days leading up to extreme winter weather.
Shallow-rooted plants, such as azalea and Japanese maple, are also prone to winter injury when they do not receive regular moisture during dormancy.
Newly planted landscapes need additional water in the winter for the first two years until the roots are established in the native soil.
Current Watering Recommendation:
We received ¼” of rain this week. If we do not receive at least a ½” of rain early this week, give your lawn and landscape a good deep soaking before the next cold front arrives.
First Step in Avoiding Winter Damage – Select plants that are winter hardy in our area.
Plant cold hardiness is based on the USDA Hardiness Zones. Central Oklahoma is Zone 7A. Plants with a 7A rating can withstand temperatures of 0 to 5 degrees. Northern Oklahoma is Zone 6B, -5 to 0 degrees. And southern Oklahoma is Zone 7B which can survive temperatures of 5 to 10 degrees.
If you live in central Oklahoma and are tempted to experiment with a plant that grows best in Zone 7B, plant it in a protected area that is shielded from dry winter winds.
Also, when selecting plants, look for plants that perform well in our tighter, clay soils. A 7A plant that grows best in loose soil may live for years when we have mild winters only to fail when we have a winter of extreme temperatures.
When making plant selections, don’t overlook ones that add winter interest such as Nandina with their bright red berries.
The best weather for your plants during extreme temperatures is a snowfall of 2 or more inches.
Snowfall is moisture!
If we get a ½” rainfall, there is a lot of runoff. But, when the snow melts, it slowly soaks in. Every single drop benefits the roots of your turf, flowers, shrubs, and trees. On average, a 4” snow equals nearly a 1/2” rainfall.
The Old Farmer’s Almanac calls snow a “poor man’s fertilizer.”
Snow is full of nitrogen. As snow falls it collects nitrogen that is naturally in the air and distributes it evenly over your lawn and landscape.
Best Weather Condition for Extreme Cold – Snow.
Fresh snow is like a warm blanket when temperatures dip into the teens or lower!
Snowfall is nature’s way of insulating your valuable landscape from cold temperatures. A fresh snow cover of more than 2” is very beneficial to the landscape by trapping soil warmth below the snow.
Without snow, soil temperatures fluctuate more, dipping deeper during cold spells. It is common for soil temperatures to be as much as 10 degrees warmer when there is a snow cover.
Your landscape is thankful for a blanket of snow to trap the warm soil temperatures around its roots and keep the cold windy temperatures at bay.
A Key to Preventing Winter Damage – Healthy Plants.
Rarely does a healthy plant die due to winter injury. Plants in poor health are the first to die during cold periods.
Keep your plants healthy during the growing season and they will be better suited for the winter cold. Inspect often for insects and disease. Make sure they are receiving the correct nutrients in the correct amounts. Practice good watering techniques throughout the growing season.
The healthier your plants, the better they will do in the extreme temperatures of winter.
One More Great Winter Practice – Mulch.
A fresh 2-3” layer of mulch will provide insulation for your plant roots, retain moisture, and moderate soil temperatures.
As always, let us know if you have any questions or if we can help you have your best lawn and landscape.
And…stay warm…. after all, it is January.
Lorne Hall
Hall | Stewart Lawn + Landscape
(405)367-3873
