Accession Count: 13
Common Name:
silver peso Texas mountain laurel
Family Name:
Fabaceae
Botanical Name:
Dermatophyllum secundiflorum
Sub Species:
Variety:
Forma:
Cultivar:
'Silver Peso'
Characteristics:
'Silver Peso' is a cultivar of the Texas mountain laurel, a native, woody, perennial broadleaf evergreen large shrub or small tree found in the southwestern United States and northern Mexico (1,2,3). It is very slow growing reaching a mature height reported to be as small as 2 – 3 m (6-9 feet) or as tall as 4.5m (15 feet) with a slightly smaller canopy width. Branches are thornless and the canopy is dense casting great shade though the growth rate is very slow (1, 2). Pinnately compound leaves have a distinctive silver-grey color as they are covered in small, fuzzy hairs in contrast to the straight species which has glossy dark green leaves. ((1, 2, 3 ,4) The flowers appear in late winter or early spring, are light purple in color, highly fragrant (like the smell of grape bubblegum) with a “sweet pea” form of papilionaceous corolla (2, 4). Flowers are arranged in a raceme inflorescence which has a distinctive 2-ranked pattern organizing flowers in pairs on opposite side of the peduncle. For this reason, the specific epithet “secund” iflora is appropriate! Thick, brown-tan seed pods containing bright red, poisonous seeds follow the flowers in summer or early autumn and spring (2, 3 ,4).
Compound:
Sop sec Sil
Geographic Origin:
Texas/Northeast Mexico
Ecozone Origin:
Nearctic
Biome Origin:
Natural History:
The ‘Silver Peso’ is a cloned cultivar of the Texas mountain laurel, Sophora secundiflora. It was selected as a cultivar for its distinctive silver-gray foliage. The straight species is native to New Mexico, Texas, and Northern Mexico where it grows in rocky hillsides, canyons, and slopes in the Edwards Plateau of Texas and adjacent regions in Mexico. The cultivar is widely used in cultivation throughout reported use in many cities from Goodyear to Tucson in Arizona as well as in Texas and California (3)
Cultivation Notes:
The Silver Peso trees are propagated from cuttings. Seed propagation is possible (though heritability of the ‘Silver Pesos’ traits from seed grown plants is unknown by the Campus Arboretum). If seed is collected, allow pods to dry on the plant, break open the pod and scarify the seed before placing in warm, moist soil and high humidity to germinate. Growth rate is slow (2, 3, 4). Texas Mountain Laurel, including the 'Silver Peso' cultivar, thrives in hot, dry climates. It is recommended for planting in USDA hardiness zones 7-9 or in Sunset zones 8-16, and 18-24 (1) though some claim it can grow as well in the intense heat of zone 10a and 10b (2). It prefers well-drained soil and is tolerant of various soil types, including sandy, loamy, or rocky soils with a pH range of neutral to strongly alkaline (2). While a pH of 8.6 to 9.0 is tolerated, the preferred condition is slightly alkaline. (2). Once established, 'Silver Pesos' is drought-tolerant and requires minimal watering (2). However, regular watering during the first few years of establishment helps promote healthy growth. The plant prefers full sun or part shade but can tolerate afternoon sun and reflected heat (2, 3, 4). Pruning is generally not required for 'Silver Pesos', but occasional shaping or removal of dead or damaged branches can help maintain its appearance.
Ethnobotany:
In its native habitat, Texas Mountain Laurel plays a role in stabilizing soil on slopes and providing habitat and food for wildlife such as birds and small mammals. While it is considered deer resistant in cultivated settings (3), it is highly attractive to pollinators including bees and butterflies. Like the straight species, 'Silver Peso' produces beautiful clusters of fragrant purple flowers in spring. The flowers resemble those of sweet peas and attract pollinators such as bees and butterflies. Some reports cite that all parts of plant are poisonous if ingested (3), it is widely known that the seeds of Texas mountain laurel contain compounds that are toxic if ingested (5). If toxicity is of concern, simply clip off the pods and dispose (2). Texas mountain laurel has cultural significance among indigenous peoples of the region. Various tribes have historically used parts of the plant for medicinal purposes, as well as in ceremonies and rituals. This plant is well suited to use in residential urban landscapes because of its beauty, environmental tolerance and smaller size. 'Silver Pesos' and valued for their ornamental appeal, including their attractive foliage, fragrant flowers, and compact growth habit.
Height:
11 - 15 feet
Width:
6 - 10 feet
Growth Rate:
Slow Growing
Grow Season:
Spring
Flower Season:
ForeSummer
Color:
Purple
Function:
Patio
Spread:
Non-spreading
Allergen:
Non-allergenic
Invasive:
Benign
Toxicity:
Benign
Hardy:
Hardy
Water Use:
Low water Use
