Patience is the key for winter damaged landscapes
While spring is knocking at the door, our landscapes are reflecting the harshness of the winter….a winter that was bookended by a record ice storm and record cold temperatures.
The normal early spring greens of the landscape have been replaced with shades of browns.
What do you do now?
The one-word answer…Patience.
Central Oklahoma’s USDA Hardiness Zone is mostly 7a with 6b just west and north of the metro area. Plants that can handle temperatures as cold as 0 to 5 degrees are recommended for Zone 7a, and if they can withstand temperatures from -5 to 0 degrees, they can be planted in Zone 6b.
The temperatures in mid-February dropped to those found in Zone 5a and 5b. You have to travel to Nebraska to be in Zone 5. Zone 5 is fine for Boxwoods but is not a good place for most varieties of Holly, Indian Hawthorn, Cedars, and many other plants we have come accustom to using in our landscapes.
Indian Hawthorns, a Zone 7-9 plant, are mostly brown after two weeks of Zone 5 temperatures.
The best plan, for now, is to pause and wait 2-3 weeks before making pruning. and replacement decisions.
You can expect your Blue Atlas Cedars and Deodar Cedars to drop most of their needles over the next few weeks.
Amazing, we are seeing signs that most plant material may have little to no damage. By the end of March, we will know more.
One of the first indications of freeze damage is cracking bark. Moisture moves from the roots to the leaves just below the bark. During periods of extreme cold, the sap can freeze resulting in cracking bark. If the bark is loose or popping off, the moisture below the bark froze. Without bark, a plant cannot move moisture from the roots to the leaves without resulting in plant death.
Another indicator is brown, to even black, colored foliage. Extreme cold temperatures dehydrate evergreen leaves and needles draining them of their color.
Leaf and needle drop can be expected. Plants that are normally evergreen in our area will see leaf drop this spring. Defoliation is a good sign when a plant has lost color. Leaf drop is a sign that the plant is alive and budding. If brown leaves and needles remain, it is a sign the plant is in real trouble.
Wait for new growth to appear before pruning. When you prune, start at the tips of the branch, and gradually move down until you see green in the cambium layer, the tissue right below the bark layer. Even if the top is dead in a broadleaf evergreen, it can fill back in this summer. Remember, you can prune holly and boxwood harshly and they will re-leaf on the stems.
If more than 30% of the top of Cedars, Pines and Cypress are dead, it is best to remove the plant. Otherwise, cut out the dead branches and reshape.
It’s common for magnolia to have some bronze leaves, many turned nearly completely bronze. Even so, their buds weathered the storm well.
Cedar branch tips are still soft and supple. A good sign that they will recover.
Typically elaeagnus is a silvery green in early March. After February’s cold spell, most are completely brown. And still most have buds that tells us they will recover.
Pine tree needles are more brown and yellow now than typically at this time of the year.
In our region, even during a mild winter, it is common to have some dead branch tips on Crape Myrtle. But after the extended cold spell in 1983, many Crape Myrtles froze to the ground. From the Crape Myrtles we have checked in the past few days, it appears that most have survived this year’s extreme cold. It is easy to give up on a Crape Myrtle too soon. They are one of the last deciduous plants to bud each spring. Give them plenty of time to respond this spring before making extreme pruning or removal decisions.
A good way to check your Crape Myrtle branches or any plant is to gently scratch the bark with your fingernail or a knife. If the cambium layer (the tissue right below the bark layer) is green, the branch is alive. If the color is faded green or brown, the branch will likely need to be removed.
Another indicator is the condition of the buds on the tip of a stem. If the bud is hard and dry, the bud is dead. If the bud is soft and supple, the branch is alive.
Sometimes freeze damaged plants will fool us in the spring. They will start growing, but then, because of their weakened condition, they will fail to survive in the summer heat.
One of the best things you can do for your plants this spring is fertilize to promote new growth. Follow label instructions. Do not pile fertilizer next to the trunk. Water well after fertilizing.
Periods of extreme cold will reveal unhealthy plants. These two cedars responded very differently to the cold. A sign that the one on the left is struggling. Most likely it has a damaged root system.
Check branches by gently scratching them with a fingernail. If the layer just below the bark is green, the branch is still alive. This Crape Myrtle is struggling with scale and it is still alive.
Check the buds at the tip of a stem. If they are soft and supple, the branch is alive. The plant may drop freeze damaged leaves, but it will recover.
Extreme cold can also be difficult on your turf as well. Bermuda, a warm-season grass, does not grow well north of central Kansas. The most important indicator for turf damage is how low the soil temperature went. During the two weeks extreme cold, amazingly, the average lowest soil temperature in the metro area was only 34 degrees. The 10” snow cover provided needed insulation for the turf.
We expect warm-season turf in full sun areas, where the turf is thick, to rebound well this spring. But, it is possible to see warm-season turf damage in areas of the lawn where the turf was already thin because it was not receiving at least 6 hours of direct sunlight each day.
We are all anxious about the condition of our landscapes. But, the best thing you can do is give the landscape time to respond.
For the next couple of weeks….just pause and wait.
If you have questions about your plant material, give us a call.
Lorne Hall
Hall | Stewart Lawn + Landscape
(405) 367-3873
