Christmas Polar Vortex
What Can We Expect For Our Plants?
As I’m sure you are well aware, the “polar vortex” this past Christmas weekend in Georgia has taken a nasty toll on our plants and especially seasonal color installations. This unprecedented weather phenomenon with three days of single digit temps and wind chills below zero degrees, is something we haven’t seen in decades.
I’ve spent the last week reaching out to friends and colleagues in the green industry to find the best information on what to expect to happen to damaged plant material, and what to do to help the plants survive. The bad news is that a lot of plants took a serious hit and look bad with seasonal color having the worse outcome. The good news is that most woody plants will likely survive and be fine long term.
100% of the plants were damaged in some way.
South-facing beds/pots sustained the least amount of loss, as that exposure gets sunlight all day long in the winter months.
Plants receiving reflected heat from roads, signs, sidewalks, and walls have less damage.
North-facing and shaded areas stayed frozen for longer periods, resulting in substantially more damage.
Container gardens and raised planters may have substantial damage. Their root systems were more exposed and stayed frozen for longer.
Pansies and violas should recover, especially with the warm rain this week.
Most accent plants will not recover from the extended freeze. acoris, heuchera, euphorbia, dusty miller MAY recover. Much depends on exposure.
“We will not truly know until spring green-up but grasses that were fully dormant likely will not have any long-term effects. Microclimates (e.g., shade) may be exceptions. In general, our turfgrasses are resilient plants and will likely be fine. Exceptions may include the stoloniferous species (i.e., centipedegrass and St. Augustinegrass) being grown beyond their ideal zone of adaptation (e.g., Macon). From a turfgrass perspective, it was better for this freeze to occur in December than in March.”
Plants in our zone (7b) have tissue that can normally handle temperatures in the single digits, but only for a short period of time. Last week’s event was much worse than normal for our zone which pushed our plants to their limits. Under the skin (bark) of a plant is its tissue. As long as a plants tissue is not damaged, the plant will survive. Areas of the plant where there is not much tissue protection, like its foliage and the growth from the last 12 months where the bark is thin, probably stayed frozen for too long to survive, especially in open unprotected areas.
We won’t really know the total effect until about March when plants will start pushing out new growth. If the tissue of the plant has survived, it will push out new growth and bounce back just fine. Again, there is no way to know for sure right now if a particle plant will survive.
I’m seeing tea olives that really look bad loosing almost all their foliage, as well as some azaleas and gardenias. The distylium, soft caress mahonia, and camellias look very burnt as well as any evergreen perennials. My two large podocarpus at my front porch look really bad, but I think they will be fine. Most of my colleagues believe these plants will survive, but we won’t know for sure the full effect of the weather event until March or April, AND we are still likely to have more freezing weather this month or next month, which would be typical.
There is also mention that hydrangeas that bloom on old wood, might not bloom this year. These hydrangeas like the nikko blue, bigleaf, and endless summer had already started to push out their growth for this year and may have been affected. We will see come spring/summer.
For seasonal color, following the warm rain this week, we saw substantial recovery in just a matter of hours. Once the top portion of the damaged flower is removed, live green growth is showing. We feel like we will see more progress in the next 2 weeks.
We here at Beyond The Curb Landscaping will be doing what we can to stay informed and do what is needed for the best outcome of all our clients’ gardens. It has been suggested that we do not do any severe pruning to damaged plants at this time to give the plants a chance to ‘recover’ from the stress of this event.
In closing, please know your plants are most likely not dead. We just need to be patient with them while they do what they do. They went into shock with how cold it got (and so did I!!) They just need a minute to ‘wake-up.’