By Jeff Floyd
Certified horticulturist and arborist
From start to finish, the Appalachian Trail is some 2,190 miles long give or take, depending on how often a hiker gets lost trying to stay on the impressive footpath. The mountainous walk takes hikers through fourteen states and past an enormous variety of plants. By some estimates, there are more than two-thousand species along the route. All of them thrive without any care. It’s the quintessential low-maintenance landscape.
A high-impact, lush landscape is the dream of many west Texas homeowners. However, our homes are literally perched on the northeastern edge of the Chihuahuan Desert. The number one limiting factor for a diverse flourishing plant palette in West Texas is water. An ample amount of rainfall delivered at appropriate intervals is critical for plant health. Rainwater is virtually free from the minerals, salts and other substances (collectively called dissolved solids) found in secondary sources of water such as municipal water supply systems.
While potable water from United States municipalities is closely regulated and almost always safe to drink, it can be more than 100 times higher in dissolved solids than rainwater. In situations where a landscape must rely significantly on irrigation water from a municipal water supply, these dissolved solids may build up near the soil surface over time.
Some plants can tolerate high concentrations of soil salts and minerals but many more will begin to show signs of stress, especially when their water demand is high as it typically is on hot or windy days. This is because the dissolved solids interfere with the plant’s ability to take up water and nutrients. A heavy rain event will flush accumulated salts below roots and simultaneously provide plants with a supply of fresh water. It’s not just your imagination that landscapes look better after rain.
With an average annual precipitation rate of only fourteen inches in the Permian Basin, poorly planned landscapes are forced to rely heavily on irrigation water. When applied correctly, irrigation water can stave off the effects of salt build-up in the soil and keep plants alive until the next rain event. Groundwater from private wells is not always a good solution since it is often much higher in dissolved solids than municipal water.
Which plants should be in our landscapes and which ones should we think twice about? That depends on your budget and tolerance for maintenance among other things. We’re going to talk about that next time. Until then, I’d like to suggest that we consider where we are geographically and begin to think about working with our regional climate instead of trying to reproduce something along the lines of what we see in Appalachia.
