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From: Lancaster, PA
Region: Mid-Atlantic
Topic: Planting, Poisonous Plants, Trees
Title: Growing a Texas Mountain Laurel in Pennsylvania
Answered by: Barbara Medford
This is one of those questions we could just answer with "no," and let it go at that. If you follow this link to the USDA Plant Profile Map for Sophora secundiflora (Texas mountain laurel) you will see that it is native only to New Mexico and Texas. There are a number of reasons why trying to plant this plant in Pennsylvania would probably fail.
1. Habitat. If you follow the plant link above to our webpage on this tree, you will note this statement:
"Native evergreen ornamental tree within its range, valued for its handsome, dark green foliage and lush early spring blooms. It is drought-tolerant, prefers rocky limestone soil, and is native from central Texas west to New Mexico and south to San Luis Potosi in Mexico."
2. Temperature: Lancaster County is in USDA Plant Hardiness Zone 6b, with average minimum annual temperatures of -10 to -5 deg. F. The Texas Mountain Laurel grows in Zones 7b to 10b.
3. Soils. Most soils in Pennsylvania are acidic. Sophora secundiflora (Texas mountain laurel) grows commonly in limestone soils, which are alkaline.
Warning: The brilliant red seeds contain the highly poisonous alkaloid cytisine (or sophorine) - this substance is related to nicotine and is widely cited as a narcotic and hallucinogen. If that is why you want to grow this plant, we don't want to know about it.
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