Sophora secundiflora is simply a really great plant for gardeners in the Pineywoods of Texas.  Whether called Texas mountain laurel, mescal bean, or frijolito, it’s actually quite common in western regions of the state.  It’s a staple of the hill country but rarely encountered in the Pineywoods.  I’m not sure why.  After all, it’s tough as nails, drought resistant, fully evergreen, breath taking in bloom and enjoys a fragrance to match.  Reported to reach thirty feet in the wilds of Texas, New Mexico and northern Mexico, most landscape specimens come in at half that.  If there’s a negative, it’s that the species is a bit of a slow grower.  We’re a fast food – fast plants society and waiting a decade or two for a plant to obtain stature and class rarely fits the bill.  There’s another minor negative characteristic I should mention.  The seed are reported to be highly toxic with as few as four masticated seed enough to have you pushing up daisies.  However, keep in mind if you swallow the seed they generally pass on through.  Best not to chew them.  Generally considered a Zone 8 to 9 plant, hardy forms are reported but remain unexploited.  Plants in Dallas and parts north have rarely appeared healthy to me but there are exceptions.


Texas mountain laurel at TreeSearch Farms, Houston, Texas


Texas mountain laurel, smooth leaves, grape-Kool-Aid fragrant flowers

Texas mountain laurel is a member of the Fabaceae and most of the 50+ species enjoy showy pea-like flowers in terminal racemes or panicles. To complicate things I must admit that botanists have renamed the species Dermatophyllum secundiflorum. This rather cosmopolitan genus features both deciduous and evergreen species.  While most Texas mountain laurels sport blue and lavender flowers, there are white flowering forms and I’ve heard of but not seen a genotype in Austin that features light pink blooms.  There is also a rarely encountered in Mexico botanical variety, Sophora secundiflora var. pulverlenta, that has pubescent gray leaves.  We have this form in the Mast Arboretum and it’s an even slower grower than the straight species.


Sophora secundiflora var. pulverlenta is the fuzzy leaf form

To grow Texas mountain laurel in eastern climes it’s important to provide superior drainage. Limestone additions to the soil are also recommended.  A berm or raised bed is perfect.  We have one white-flowered form that rests on the corner of College Avenue and Wilson Drive.  It’s had a hard life but makes a dramatic show every year.  So, how to multiply this?  Well, grafting works but it’s not really much of an option because the plant often sends up shoots close to the base of the plant.  There’s another way.  We have seedlings of the white flowering form and once they bloom, are rogued to get rid of the blues, and the process repeated for five or six generations, we should be able to stabilize the white form from seed. Because we have so few Texas mountain laurels in our city, there shouldn’t be any worries about pollen pollution.   I’ve put some math to this and my calculations indicate that I’ll be about 100 years old when we reach the fifth or sixth generation.  For some reason, that really doesn’t appear to one of my best plans.


White flowered form at SFA Gardens, corner of Wilson and College Ave


White flowered form at SFA Gardens

With a name like mescal bean, you might think something is awry here.  Is this a drug.  The answer is yes but there’s some nomenclature issues here.  Having had some experience in Mexico, a short explanation is in order.   Mescal is a distilled beverage made from Maguey agave. Mescaline is a psychedelic alkaloid occurring in peyote cactus which has been enjoyed for millennia by our southern neighbors and in very tight knit clans in our own country.  Mescalbean beans are different and do not have either mescal or mescaline, but they are packed with a poisonous alkaloid cytosine, which is chemically similar to nicotine. Mescalbean beans are reported to have been used by some native American tribes as a way to make a kind of hallucinogenic contact with the other worlds.   I understand that there’s a really fine line between getting high and getting dead.  I had a friend who told me he once enjoyed a Mexico mountain experience with villagers.  I asked him how did it go?  He said, “Well, personally, I found the hallucinations rather mild.”   My conclusion was it might be best to stay with Miller Lite.


Sophora secundiflora seed


Handling sulfuric acid requires caution

Seed propagation is easy but involves a 45 minute to one hour soak in sulfuric acid to scarify the seed.  In the deep South, it’s a great scarification lab exercise as long as the safety lesson is well explained.  Spilling sulfuric acid on you or your clothes is a sad picture. To avoid all that, a hobby gardener can simply use a file to cut through the tough seed coat.  We have rooted the species but it’s reported to be very difficult and percentages are low.  Years ago, Nathan Unclebach, a student of mine, took on the impossible task of rooting the white form and he did get about a half dozen to root and grow.  I concluded it could be done but told him it was best to hang on to his day job.