Plant of the Week
March is upon us and so is spring. Questions about the purple-blue blooms hanging in clusters and having the wonderful scent of grape chewing gum have begun! People are once again enjoying the large evergreen shrub that grows all over South/Central Texas and is referred to as the Texas Mountain (Mt) Laurel. The scientific name of the Texas Mt. Laurel is Sophora secundiflora. The genus name, Sophora, is from the Arabic name, Sophero, and the species name, secundiflora, refers to the one-sided inflorescence. Other vernacular names are the Mescal Bean, Frigolito, Frijollito, Frijolillo, Coral Bean, Big-Drunk Bean, and Colorin. The Mt. Laurel is practically indestructible as a landscape plant. It will survive in our poor alkaline soils. The plant is native to the limestone soils in central, southern, and western Texas, New Mexico, and northern Mexico. It is not the same Mt. Laurel found in the Eastern United States-that species will not survive in our area of Texas and our Texas Mt. Laurel does poorly in those “foreign” areas.
Nothing seems to bother the hardy, drought-tolerant, grow-in-a-stone Mt. Laurel. Hard freezes (below 20 degrees F.) eliminate blooms but won’t kill the plants. These natives evergreen shrub seem resistant to the dreaded cotton root rot fungus which is deadly to 90 % of all other Texas landscape plants. No foliage disease bothers the glossy, evergreen leaves. Every now and then foliage worms may devour some leaves, but the plant comes right back, which can be treated with Bt worm killer. Because the Mt. Laurel is an evergreen shrub (or tree) which can be from 8 to 12 feet in height or as high as 30 feet, this may be the ideal privacy plant for this area of Texas. What other evergreen is so durable and adapted – None! Plus this native plant blooms in the spring!
These beautiful plants are the answer to many of this area’s most serious plant problems. In the past, this outstanding landscape plant was only available as balled-and-burlapped (B-and-B) plants in the nurseries. Large B-and-B trees and shrubs dug from the wild are very expensive because of the tremendous amount of labor involved: in digging the plant, in burlapping it, and in hauling it away. The newly dug B-and-B Mt. Laurel must then be cured (let it stand in a location to see if the plant decides to live or die) for 3 months until sprouting occurs.
As many as 50 % of all the Mt. Laurels dug out do not survive this process. It is no wonder that your cost for a four to eight foot, multi-trunk Mt. Laurel may be over $300! Because of some innovative work in propagating native plants of Texas by Lone Star Growers (now Color Spot) in San Antonio, Mt. Laurels are now available as container-grown plants and are very affordable. For years these plants were described as “slow growing” and impossible to grow economically in containers. Modern technology and persistence have paid off. Large containerized plants are currently available in local nurseries. Plants, three to four feet tall, in five-gallon containers cost less than $25 each. Smaller plants, one to two feet tall, in one-gallon containers cost less than $7. As the plants begin to flower and the demand for this beautiful well-adapted plant increases, some nurseries actually sell the small plants for less than $3 and the larger plants for less than $17.
With the availability of inexpensive containerized Mt. Laurels, you can use these evergreens, blooming plants for creating a privacy hedge or shrub mass. Every good landscape in this area should now contain several Mt. Laurels. To plant the containerized Mt. Laurels, simply dig the hole as wide, but no deeper than the container. Use the soil pulled out of the hole to fill around the plant or as your back-fill soil. Make a circular dam around the hole (this makes watering easier). Water in thoroughly after transplanting to settle the soil around the root system.
So there you have the story of a native Texas plant with the inappropriate name of Mountain Laurel making it big in landscapes. Enjoy the fragrance and enjoy the beauty of a Texas Mountain Laurel in your landscape. And DON’T be trying to get the recipe perfected-this plant is for beautifying the landscape-not sending you into a drugged state of euphoria!
David Rodriguez is County Extension Agent-Horticulture, Bexar County. For more information, call the Master Gardener ‘Hotline’ at (210) 467-6575 or visit our County Extension website at https://bexar-tx.tamu.edu, click under Horticulture and Gardening.