WATER WISDOM FOR LANDSCAPES DURING WINTER
By Marigay Black, Grayson County Master Gardener
Winter maintenance of our perennial landscape plants can be care-free by following recommended guidelines offered by Texas A&M at WaterUniversity.tamu.edu.
One of the best protectors for our plants is adding a 3-inch layer of hardwood mulch around the crown and out to the drip line of the plant which will protect the root zone from freezing temperatures. It’s not necessary to pile the mulch up onto the stem or main branches. You don’t even have to cut the branches down to the ground or rake all the leaves just yet – wait till springtime to put that on your to-do list. The branches and leaves that are left can provide protection for lizards, frogs, and birds, and the eggs and pupae of certain butterflies which overwinter on leaves and stems.
Thankfully, we don’t need to water as often as we do in summer but when it’s necessary, place the water directly onto the soil, avoiding moisture on the leaves and stems. The plant cells retain water to help make it resilient to freeze but too much water can lead to damage or even dying. Watering earlier in the day is best so that the roots have time to absorb it before the nighttime. Irrigation system controls and timers should be turned off when a freeze is expected. Water only when temperatures are above 45 degrees. Making sure your soil is moist before an expected freeze will help to protect the roots from damage. This applies to plants that are in the ground and our potted plants.
Covering sensitive plants with freeze-protection fabric or old sheets can help hold the heat closer to the soil but should be removed once the temperature rises above 32 degrees Fahrenheit. I use this method for a few plants I want to overwinter, like citrus and my favorite geraniums. Their cold hardiness rating is for warmer climates, and they won’t survive if exposed to the first freezing snap that north Texas can experience.
Choosing landscape plants that are native or well-adapted to our cold hardiness zone is the best defense against our sporadic temperature swings. In 2012, the USDA established maps showing the average coldest temperatures by geographic areas. The zones in Texas range from 6b in the Panhandle to 10a in the southern tip of the state. The north Texas area falls into zones 7b to 8a – low temperatures ranging from 5 to 15 degrees Fahrenheit. When you buy a plant, it will have a tag on it with planting and care instructions, and the hardiness rating will be on the tag. The higher the number on the rating, the less likely it will survive our cold temperatures, and the more steps we have to take if we want the plant to make it through our winters.
Your AgriLife Extension office at the courthouse in Sherman is a great in-person resource for everything plant related, and they’re open Monday through Friday, normal business hours. There are several web sites that can guide us to the right plant choices for optimal success – which translates into saving money, less maintenance work, and a beautiful landscape to enjoy. Start at aggie-horticulture.tamu.edu, and navigate to their Earth Kind and Texas Super Star links. Another comprehensive web page is the Ladybird Johnson Wildflower Center at wildflower.org. Look for the Native Plants section. Another of my favorites is the Native Plant Society of Texas at npsot.org. Each of these sites will lead to other links and information on landscape design, figuring out your soil type, average rainfall, temperature ranges, and choices of plants from ground cover, shrubs, flowers, grasses, and understory trees to majestic canopy trees.
As always, the Grayson County Master Gardeners are ready to answer questions. We look forward to hearing from you!
Grayson County Master Gardeners Association is a non-profit 501(c)(3) organization sponsored by the Texas A&M AgriLife Extension Service. Reach us by email at firstname.lastname@example.org, by phone 903-813-4204, our web page graysoncountymastergardeners.net, or our Facebook group.