Texas Mountain Laurel

Sophora secundiflora – Texas Mountain Laurel, Mountain Laurel, Mescal Bean, Frijolillo

A favorite ornamental, this shrubby evergreen can be trained into a small, multi-trunk tree. Texas Mountain Laurel is a great option for small spaces and anywhere that could benefit from some green in the winter months. The prized feature is the profusion of sweetly fragrant lavender flowers in early spring followed by distinct, elongated seed pods. Mountain Laurel attracts pollinators and birds. This tough, drought-tolerant Texas native may be slow-growing but is adaptable and well worth its place in the landscape. A good, native replacement for the invasive ligustrum or privet.

Growing Requirements

Light: Full Sun, Partial Shade, Shade
Water: Low

Grows in sun and shade though it may not flower in shadier spots. Highly adaptable to soil types but requires good drainage. To improve drainage plant in a berm or small hill to plant in. Or amend the soil with compost or expanded shale. Never plant in a low spot. Very heat and drought-tolerant once established. Cold hardy to around 10-20°F so be mindful of placement; best placed in a spot protected from the north wind in winter. Protect young plants with frost cloth if temperatures are due to drop too low. Established plants tend to be more hardy.

A long tap roots makes Mountain Laurels drought tolerant but also means they do not like to be transplanted. Smaller nursery specimens may have a higher survival rate. 

In the Landscape

Average Size: 10-30 feet tall x 7-12 feet wide
Spacing: 10 feet
Classification: Large Shrub, Ornamental Tree, Evergreen Tree
Uses: Border, Specimen, Mass Planting, Container, Shelterbelt, Understory Tree, Fragrant, Wildlife Habitat
A versatile plant for most any landscape. Usually seen around 10-15 feet tall but can grow as big as 30 feet under ideal conditions. Grow as a compact, upright shrub; train into a tree form; or prune into an informal hedge. The dense evergreen foliage makes it especially good for screening or as a windbreak. Also does well as an understory planting beneath large shade trees such as oaks and pecans (though it may grow more slowly in filtered shade). For smaller spaces, it can be grown in a large container or espalier. 

In a landscape plan, Mountain Laurel creates an attractive evergreen backdrop for perennials that may go dormant over winter, like Wood Ferns, Pigeonberry, and Coralberry. Plant with other drought-tolerant sun-lovers such as Desert Willow, Salvias, and Coneflowers. Or with evergreen shrubs and ornamental grasses for a naturalistic screen grouping. Good accent for a patio, pool, or small landscape.

Seasonal Interest: Spring, Summer, Fall
Showy, bluish-purple drooping clusters of fragrant blooms appear in the early spring and fade to lavender. The eye-catching flowers have a strong fragrance reminiscent of grape candy. Glossy, bright green foliage with rounded leaves makes a striking contrast to the blooms and provides interest throughout the year. Attractive dark-brown seed pods adorn the tree in late summer and fall. Note: The red seeds, called mescal beans, are poisonous if swallowed but are protected by the hard outer coating. 

Wildlife: A nectar source for butterflies and bees and provides shelter and nesting for birds. Deer and rabbit resistant.

Care & Maintenance

Blossoms form on year-old wood, so any pruning should be done after blooming. Trim to shape (but do not shear). For a tree-like form, remove lower branches, leaving three to five trunks. To maintain this shape, remove suckers as they appear. Remove no more than one-fifth of the shrub at a time. If you leave the suckers, it may gradually form a thicket. Do not shear. 

Apply organic fertilizer (or compost) just before new spring growth and again in fall for heavier blooming. Occasional feedings and water will encourage faster growth. Water deeply about once a month or so during prolonged periods of drought; avoid over-watering. Check soil moisture level with a moisture meter before irrigating.

Problems & Troubleshooting

Texas mountain laurel is a host plant for the genista broom moth caterpillars (Uresiphita reversalis), sometimes called the Sophora worm. These feed on branch tips anytime from spring through fall, favoring tender new growth. Look for loose webbing on the ends of branches. To control, start by handpicking the worms or removing infested tips as soon as you see them, or spray with high-pressured water. Or simply tolerate these native moth caterpillars! Though a large infestation can defoliate a plant, generally the damage is mostly cosmetic.

Worms are more likely to attack stressed or heavily watered plants, so be sure to decrease watering once established. Overwatering and poor drainage can be responsible for overall poor health of the plant.

Late spring freezes may nip the buds and decrease flowering. An unusually hard winter may kill unprotected young plants. Wait three months before giving up on the plant; it may grow new roots and recover in this time.

Resources and References

Lady Bird Johnson Wildflower Center | Native Plant Society of Texas
Landscaping with Native Plants of Texas by George Oxford Miller
Native Texas Plants by Sally Wasowski and Andy Wasowski

1. Photo by Nate Sabo via iNaturalist, licensed under CC BY 4.0. Original image cropped with minor exposure adjustments. ↩︎
2. Photos by (L) Tyler Cannon via iNaturalist, licensed under CC BY 4.0; (R – Mescal Bean) Ken Bosma via Wikimedia Commons, licensed under CC BY 2.0. ↩︎
3. Photos by George via Pixabay. ↩︎