Facts and myths you need to know when it comes to North Texas gardens and landscapes
There's going to come a day when I'll have to hang up my typewriter (preferably not soon). I'll hope by then to have brought at least a little light to the North Texas gardening world. Hopefully I'll have exposed all the scams and scandalous claims that are being made in this, the world's greatest hobby. There are many myths cast about as if they were fact, and I'm here today to sow more seeds in my field of enlightenment.
That is a true statement. Just because a plant grows wild in the swamps of Southeast Texas or the deserts of West Texas, it doesn't get a blanket approval everywhere else in the state. Texas sage plants from Southwest Texas freeze in North Central Texas. Many types of yuccas get too much rain here. Our soils are too alkaline for bald cypress, water oak, and most types of pine trees. If you want to plant a "native" plant, choose one that is native to your town. Those plants from distant places aren't truly "native" here for a reason.
But isn't it amazing how many times you hear of "miracle" grasses that can grow in all kinds of shade? Folks at the Astrodome would have loved to know that 60 years ago. If you can associate thinning spots in your turf with increasing shade nearer the trunks, you've identified the problem. Don't waste your money on grass varieties that make those extravagant claims. If you don't get 5 or 6 hours of strong direct sunlight, even St. Augustine (our most shade-tolerant turfgrass) will have a hard time surviving. It's time to switch to a shade-tolerant groundcover.
Fact! Remember that the next time you hear someone ask, "What's a good fast-growing shade tree?" There simply isn't one. All fast-growing shade trees have at least one fatal flaw that will limit their life expectancies to 15 to 30 years. Tell your Texas certified nursery professional that you only want a top-quality tree like a live oak, Shumard red oak, chinquapin oak, bur oak, cedar elm, pecan, or Chinese pistachio. If you need an evergreen, eastern redcedar or southern magnolia would be excellent.
That is my personal opinion. It does not agree with the two most recent USDA Zone maps of 2012 and 2023. Smart people with lots of data drew up those maps. In each case, they show us as having warmer winters than in 1990. Our North Central counties were shifted into Zone 8, predicting that the lowest expected temperature each winter would be 10 to 20 degrees.
We have had a couple of winters since 2012 where the lowest temperatures were significantly colder. Big parts of our area dropped to or below freezing in February 2021, and Zone 8 plants were all lost here.
My suggestion: Consider this area to be Zone 7 and use the Hardiness Zone map of 1990. Hopefully you have an older gardening reference book that will show you the old map. It's difficult to find one online. All I found was one of my own stories where I compared the 1990 and 2012 maps.
That is another true statement, and it's only true because our state has no requirement that "If you're going to claim it, you're going to have to prove it" when it comes to improving our soils. I can sell you a bag of broken bricks and claim they will loosen your tight clay ground. As long as I don't claim they will add fertility or control insects or diseases, I can throw out those claims.
Some states don't allow that kind of misinformation, but Texas does. Maybe our new legislative session could take this under consideration. In the meanwhile, just use your best judgment. If something is claiming to "stimulate the microbes" or "activate the enzymes," you'd better look for validation from a real Land Grant (ag college) University like Texas A&M. That product is probably a waste of your money.
"Pruning back" may be a clue that you have the wrong plant. People often ask me for advice in "pruning back" various shrubs. That usually tells me they've chosen the wrong plant for that spot in their landscape. If it's grown too tall or too wide, cutting it back is just going to put off the inevitable. It has a pre-determined genetic height that it's trying to achieve. Cutting it back will just delay its arrival at that mature size. It also will weaken the plant. It's probably time to remodel and replant.
I've saved my most heartfelt message of all for the last. I've spent my entire career trying to get my fellow Texans to quit topping these glorious plants. There is absolutely no reason to do this. It ruins their natural growth form. It doesn't keep them shorter. It just delays their getting taller. It doesn't improve their flowering — it delays their first blooms each summer and reduces the total numbers of bloom cycles from possibly four times per summer down to just one. Don't do it, please.
