East Texas Ag News: First frost marks end of current growing season

ANGELINA COUNTY, Texas (KTRE) - Did you get your first frost?

Folks like us who work outdoors can get obsessed by frost. We know that the first frost is an important date. We understand that the first frost of the season heralds the end of the current growing season.

First frosts are a major marker for agricultural producers, gardeners, and landscapers. Frost effectively ends the growing season for several warm season annuals and puts many perennials into their winter slumber.

Frost also matters to livestock producers because it ends the growing season of their warm season pastures. If pastures can still provide grazing for livestock, then stockmen can delay the feeding of hay which is one of the biggest expenses of the year.

Following the cold snap earlier this week, I checked in with friends around the area and found that the results were mixed. Some saw a hard frost and others did not notice any issues. Kim from Wells said she only had minimal damage to plants while the Caddo Mounds outside Alto had a hard freeze. Harold from Lufkin didn’t see any. Andrea at The Pouland’s Everything Store in Diboll said residents of Buelah saw a hard frost. My buddy John told me he didn’t notice any frost at his garden south of Lufkin. Tommy from the Davisville area (between Lufkin and Nacogdoches) said his tomatoes were bit hard. My tomatoes in Clawson are still in fine shape.

Historically, the average first frost for our area is mid-November. A couple of years ago in 2019, we had a hard freeze on Nov. 1, a full two weeks ahead of the anticipated average frost. Records from the weather station at the Angelina Airport in Burke indicate the first frost in 2020 to have occurred on Nov. 30. Last year in 2021, it was late December for most Angelina County residents before they saw weather cold enough to produce frost.

Yet for many around the area, Wednesday, Oct. 18 is what they will record in their notebooks for 2022. That is a full month ahead of the historical norm. There is no telling when the rest of the folks I spoke with will see a frost.

Let us look at what really happens when frost covers a plant. When water gets below 32, ice crystals that form inside tender leaves will rupture the cells and, effectively, kill it. Anything from 32 down to 29 degrees is generally considered a light freeze (or frost). Temperatures that dwindle down to the 28 to 25 range are expected to be widely limiting to most vegetation. Only a few native or well adapted plants will continue to grow with temperatures below 25. In February of 2021 during winter storm Uri, we truly learned what were the toughest plants in our area as the temperature went into the single digits.

Now what can you do to protect your remaining warm season plants that are still thriving? Irrigate and cover.

Irrigate before it freezes. Moist soil can hold four times more heat than dry soil. It will also conduct heat to the soil surface faster than dry soil, aiding in frost prevention. In a study performed years ago, the air temperature above wet soil was 5 degrees F higher than that above dry soil and the difference was maintained until 6 a.m. the next morning.

Covering plants with a bed sheet can give you 2 to 5 degrees of protection. The covers can be laid right over the crop or can be supported above the plant material on stakes. The varying degrees of protection lies with whether the cover touches the plant. Any material can be used to cover plants. However, woven fabrics are better insulation than plastics or paper.

Smart gardeners already have winter vegetables growing that can withstand our typical winter weather. Which garden vegetables can tolerate a light frost? The Michigan State Extension Service lists these as able to withstand a light frost: beet, broccoli, cabbage, carrot, cauliflower, celeriac, celery, chard, onion (plants), parsnip, and radish.

Really cold tolerant plants that can sustain hard frosts below 28 F include: collards, endive/escarole, kale, kohlrabi, lettuce, mustard, onion (sets and seeds), potato, rhubarb, rutabaga, spinach, and turnip.

Whether you saw frost this past week seems to have varied tremendously. Looking at a 10-day forecast shows no more cold weather through the first week of November. What we would really like to see is rain.