When the New Year began, I thought that surely 2021 would have to be better than 2020. COVID-19 would go away. The economy would rebound. Unfortunately, Mother Nature had other things in mind. I should have suspected something might be up. This is Texas, after all. A January 10th six-inch snow was the first act. It was a pleasant surprise, and our Pineywoods gardens turned into a winter-wonderland postcard. That event will end up as the third or fourth highest snowfall on record, but temperatures were fortunately modest, falling into the low twenties in our region. Pine boughs fell across the forest floor and some trees tipped over, but in general most of us rejoiced at the beauty of our East Texas home.
Mild temperatures followed, and then Mother Nature said enough of this good cheer. She sent another Arctic blast of epic proportions to all of Texas, every county in Texas, and no part of the state was unscathed. With a predicted low of 7° F, I woke to six inches of snow over a sheet of ice and a low of -2° F registering on my two thermometers. I was trapped on a hill. My community water quit, and the electricity flickered off — and stayed off for seven days. Still, I had firewood, food, candles, a lantern, two dogs and stockpiled water. On the fourth day of solitude, during an afternoon trek on my farm, my black dog “Bear” snagged a rabbit, and, for just a moment, I considered wrestling the rabbit away from him for my own dinner. That thought passed, and I knew I had to get to town.
“The sooner the gardener loses certain kinds of innocence the better, and there is no better place to begin than with the weather.” — Henry Mitchell
HISTORY OF COLD SNAPS
If you like math, you’ll discover that about every 15–20 years we get an epic-freeze event, one that makes the Texas record books. The February 14–17, 1895, snowstorm is still referred to as the Valentine’s Day freeze, an event known for record snowfall on the Coast. Galveston reported snowfall over 15 inches, with Houston, Orange, Stafford and Columbus all reporting 20 inches. Even Brownsville at the southern tip of Texas received five inches, and the huge “winter-garden” vegetable industry was destroyed. To add to the wound, only a few years later, one of the worst winter storms ever in Texas struck Feb. 11–13, 1899. The entire state was impacted, and newspapers then described it as the worst freeze ever known in the state. To this day, 1899 holds the record temperature low for many Texas locations. Brownsville’s temperature reached a low of 16° F on the 12th and remained below freezing through the 13th. The vegetable crop was once again wiped out.
There are other epic freezes in Texas history, of course. My Dad spoke of the 1929 freeze, when ponds froze and the air remained bitterly cold for weeks. Yes, 1947 and 1951 brought serious low temperatures, and 1960 brought record snowfalls. 2011 had a single-digit cold snap, and in January 2018 Nacogdoches dipped to 10° F for two nights in a row.
However, in more recent history, there are two mega events that stand out. The December 1983 freeze-event had statewide impact and lasted more than two weeks. Six years later, the December 1989 freeze lasted two weeks with lows in the single digits, and damage was everywhere. Ponds froze over, cattle and crops suffered, and the zonal denial of the 1980s came to an end. It has been over 30 years since a really big-freeze headline hit the news. Yet, those and other events in the last 30 years do not hold a candle to the February 2021 freeze. Texas has a brand-new benchmark.
WHAT TO DO BEFORE A HARD FREEZE
If you’re a gardener, it’s generally accepted that the most tender plants benefit from being tucked in close to a building and that the south side is preferred. It’s good to go into a hard freeze with good soil moisture. Dry soils give up heat faster. When possible, covering tender plants helps. Nurseryman often lay over container stock and cover with frost fabric, sometimes with two or three layers. The goal is to capture as much ground heat as possible and keep it near plants.
Of course, the longer the cold spell, the less effective covering becomes. There’s only so much heat to give up. You can shovel nearby soil or pile mulch into a mini-volcano to protect the trunk and lower branches of tender trees (like citrus). “Banking” trees is particularly important if they are grafted plants. Losing the top and not the rootstock are little solace. Then, there are enthusiastic gardeners who build structures around precious plants and provide some kind of heat. For most of us, that’s not possible or we just don’t have time and we choose to watch the thermometers and pray.
WHAT TO DO AFTER A HARD FREEZE
After removing any frost fabric or removing banked-in soil or mulch, it’s best to do nothing. While it’s tempting to grab the loppers and go to town, it’s best to wait. Palms may linger for months before any signs of life. Some plants may push new growth that may die later in the summer from damage below. Patience is the rule.
Once a plant has partially recovered, and you can see what new growth is doing, only then should you pull out the loppers and saws. Cutting back to healthy new growth is painful, but it’s part of the path to recovery.
GATHERING FREEZE-RESPONSE DATA
While it’s sad to see old friends go, there is an opportunity to come back and garden smarter. I am pleased to report that Dr. Mengmeng Gu, TAMU Agrilife Extension Specialist; Adam Black, a good friend and premier botanist; and a gathering of like-minded souls are attempting to compile the treasure trove of data in front of us. Basically, we’re here to find out what thrived, what survived, what died and write it all down. Together, we intend to build a statewide tome on how Texas landscape plants fared in the February freeze. We will document freeze impact with a damage-rating scale that’s rather simple:
FREEZE-DAMAGE RATING SYSTEM FOR WOODY TREES AND SHRUBS
1: no damage.
2: minor foliar damage/partial defoliation, buds/stem survive.
3: total foliar damage/defoliation, buds/stem push new growth.
4: Outer branches dead, inner branches/mainstem survive, likely to recover in 1–2 seasons without aesthetic disfigurement.
5: Major branches/main-trunk damage, buds break but may have permanent aesthetic disfigurement.
6: Total death.
At its most basic, the project will identify the location, genus, species, variety, damage rating and observations. In the midst of death and destruction, there are data. For the botanical garden community, this is an opportunity to create a reference document for selecting ornamentals for Texas with freeze tolerance in mind.
WHAT WE KNOW SO FAR
It will take six months to get a full assessment on the impact of the February Arctic storm. While it’s still early, we can say for much of Texas, gardenias, pittosporums, Indian hawthorns, loropetalums and an array of evergreen viburnums took a heavy hit. In general, older plants fared better than youngsters. Camellias approaching or in the midst of flowering suffered more than those with tight buds. The same was true with our blueberry collection. Loropetalums are of particular interest because the plethora of varieties in the mass market never entered the trade until the early 1990s. Thus, they have never really been tested. Yes, they have survived high single digits in our area, but -3° F is another story. At this time in early April, they look like toast.
The response of commonly encountered landscape plants is easy to determine because they are everywhere. While it’s important to document the common, Dr. Mengmeng Gu and I are interested in the less well-known species, the rarely encountered plants we think might have value in the landscapes of the future. This freeze event ticks another box: hard-freeze tolerance.
Will anyone care that our Quercus insignis died outright but the rare Quercus tarahumara is coming back from the trunk and main branches? Isn’t it encouraging that most of the Mexico oaks thrived? Our broad collection of illiciums came out unscathed. Our Mexico mountain sugar maple work continues with mature trees suffering no damage. Our army of tall stately taxodium selections came through with no damage. Even the Montezuma cypress of Mexico didn’t care. Obviously, carrying the genes of 60+ million years includes freeze-tolerance as part of the mix of characteristics worth keeping.
Our 100+ varieties of crapemyrtles have a range from no damage to dead to the ground. With more than 500 varieties of azaleas at the SFA Gardens, we have a few dead forever and some left unscathed. Many evergreen azaleas, indicas and kurumes lost their foliage but have managed to bloom nicely. Are these, for just a moment, now deciduous evergreen azaleas? One thing for sure, there are many rarely encountered woody plants that survived or didn’t, and we’re here to document that. Stay tuned.
I always suggest it’s best to have about 80% of a landscape that’s bulletproof. Good friend and fellow gardener Greg Grant might suggest 90% and he may be right. For Texas gardeners that means choosing plants that are freeze, heat, flood and drought tolerant. Having a backbone of durable landscape plants means less work and fewer heartaches when climate disasters occur. I call these climate-change friendly plants for a 21st-Century Texas. Those that skated through 1983, 1989 and 2021 are a good starting point.
“It is not nice to garden anywhere. Everywhere there are violent winds, startling once-per-five century floods, unprecedented droughts, record-setting freezes, abusive and blasting heats never known before. There is no place, no garden where these terrible things do not drive gardeners mad.” — Henry Mitchell, Essential Earthman tg
Dr. David Creech
Director, SFA Gardens, Stephen F. Austin State University, Nacogdoches, Texas