Clean-Up After the Polar Vortex #springgardening

Wallace Gardens
by Wallace Gardens
This is not a pretty post. But it can become one.
Here in Zone 7B (Suwanee, GA) we had a wicked winter, like much of the country. Temperatures were well below normal, and the wind-chill factor hovered around zero on more than one occasion. All this has taken its toll on our plant materials, but with spring on the horizon, it's somewhat amazing to see how little permanent damage was actually done.
The worst problems for some of my clients seemed to be with plant materials that (1) were installed in the late fall (November 2013), just a couple of weeks before temperatures dropped dramatically, and (2) with a few established broad-leaf evergreen trees and shrubs - in the way of "leaf burn," aka desiccation. Desiccation occurs when harsh winds and cold temperatures remove the moisture from plant foliage, faster than the root systems can replace lost moisture. (That's why it is a good idea to water around the root systems of newly installed materials several hours before a freeze: this allows the roots to pass moisture to the foliage before the foliage is disturbed by frigid temperatures.)
Below are examples of plants with desiccated foliage, and some suggestions to help them recover.
As a general rule: wait until all danger of frost has passed before attempting any pruning on trees and shrubs. Plants that look dead may actually be alive, and begin to push out new foliage from bare branches once spring growth resumes. Allow burned foliage to fall naturally from the branches of broad leaf evergreens, and wait to see if new growth emerges.
Newly planted trees may experience "frost cracks" along the trunks. This is caused by an unseasonable and sudden drop in temperature. The moisture within the trunk can freeze, causing a split along the trunk. The tree will heal itself, if the frost crack is not too severe.
More Info:
http://www.ces.ncsu.edu/depts/hort/consumer/weather/coldprotect-shrubs.html
The first polar vortex arrived in early January 2014, and was followed by a 2nd polar vortex, and then a snow storm, and then an ice storm. More than some of our plants could manage...
I wrapped some of my client's more valuable and vulnerable container gardens. This saved the lives of a number of tender items like this tree ivy, masquerading here as a Bandit lurking on my client's back porch.
Two newly planted Camellia japonica shrubs - I covered as many of these as physically possible, not just once, but twice, to protect them against the sudden temperature drop.
The unveiling of the flannel sheets: newly installed Camellias remained fully covered for two days in the first polar vortex.
The pretty pink photo is just the plant tag of a newly installed Camellia japonica 'Pearl Maxwell.' This is the unveiling after a second polar vortex in early 2014. The foliage and the bugs are still in tact.
These established rhododendrons curled in upon themselves as a defense against the winter chill. Remarkably, they recovered fully after looking so terribly sad.
Here we have a newly installed Camellia japonica. This is one of the plants that wasn't covered. The obvious leaf burn is apparent.
Even though these newly installed Camellias have been damaged by the winter weather, the branches remain flexible and "green" underneath. We will wait until mid-April to see if they will recover on their own.
These fully established Camellia japonicas came through the polar vortex with flying colors, buds and foliage in tact, no covers necessary.
Evergreen ferns, like this Holly Fern (or Autumn Ferns and Christmas Ferns) need a little TLC. Just cut the burned branches down at the base. This will encourage lots of new growth in the spring.
Evergreen perennials, like this Epimedium, were badly burned this year. Just cut the foliage down to the ground, and this plant will bounce back in no time.
Another evergreen perennial: Lenten Roses took quite a hit this year. The clean-up is quick and easy. Cut the burned leaves down at the base of each plant. Then take a look at the next photo!
Lenten Roses: cutting off all the burned foliage allows the plants to show off without the distraction of last winter's weather damage. Can you see all the new babies coming up from the base? These plants are tough as nails.
Alas, this newly installed Camellia japonica, which was not covered, will probably not recover. Branches are brittle, and show no signs of life.
Most of the hydrangeas I installed last year are making a come-back just fine. I couldn't cover all of them, but so far, they are all in good shape. See the new growth coming out of the dormant stems?
This evergreen Gardenia 'Crown Jewell' has some leaf burn. Wait until mid-April to prune away the damaged branches.
Many evergreen Azaleas, newly installed and established, suffered frost bite. Again, wait until mid-April before removing the damaged branches.
More leaf damage on this Gardenia 'Radicans.' Gardenias have a particularly hard time with unusually cold winters, but they will be fine, after the damaged branches are trimmed away.
A newly installed Anise 'Florida Sunshine' (evergreen shrub) suffered only minor leaf burn. Once spring gets underway, a little fine-tuning and this shrub will bounce back with vigor.
This established evergreen understory Magnolia took quite a hit. Lots of leaf burn. Take a look at the next photo to see how you can assess the health of your trees and shrubs, by scratching a branch with your fingernail.
This is the branch from the winter-damaged evergreen Magnolia. That little fingernail scratch reveals a bright green patch - that tells us a lot about the health of both the tree and the branch. Wait to prune till mid-April.
You may notice a lot of scorched leaves on Boxwoods. Wait until mid-April to give them a prune. The warmer weather will promote new and healthy growth.
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  • Wallace Gardens Wallace Gardens on Mar 12, 2014
    I know EXACTLY what you mean @Jeanette S . You live in the Atlanta area too. Our front yard looked like it was full of corpses !! Good luck on your spring recovery.
  • Jeanette S Jeanette S on Mar 12, 2014
    You too. This year it is going to be container garden...something to eat.
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