Baja California Sennah. Senna purpusii, Family ( Fabaceae ) , Baja California Senna. Also Called: Senna, Cassia purpusii, Adipera purpusii. We wish to thank Wikipedia, the free encyclopedia for some of the information on this page. We share images and information with Wikipedia. This senna from Baja, Mexico blooms almost year-round; especially during the winter months. Its has rich yellow flowers which develop into deflated seed pods. Cassia purpusii is drought tolerant, although it does like to take additional water in a well-drained soil. It has yellow flowers in the spring and fall. Cassias attract a variety of butterflies. Quick Notes: Height: Up to 3 or 4 feet tall and 3 or 4 feet wide. Flowers: Bright yellow 3/4 inch buttercup shaped, yellow; 5 - 8 in a cluster, blooming often into summer. Flowering Time: January - April. Seed Pods: 1 1/2 - 3 1/4 inches long; narrowly oblong, flat, thin pods; short-pointed at ends, yellowish-brown; maturing and falling in summer; 2-8 beanlike seeds. Seeds: Seeds are dark red - brown. The smooth hard seeds are only slightly flattened with 2 to 7 found in each pod. Stems/Trunks: Trunks are about 2 - 3 inches in diameter. The branches and most of the main trunk are blue-green becoming manzanita-like red/brown. Leaves: The leaves are small, round, stiff, blue-green, outlined in purple. Found: The USDA claims it is native to the USA (AZ, NM, TX). In Arizona it is native to Pima county. In Mexico it is in Baja Norte, Baja California, Chihuahua, & Tamaulipas. Hardiness: Root hardy to 20 �F USDA Zone 9b: to -3.8 �C (25 �F) USDA Zone 10a: to -1.1 �C (30 �F) USDA Zone 10b: to 1.7 �C (35 �F) USDA Zone 11: above 4.5 �C (40 �F) Soil pH requirements: 6.1 to 6.5 (mildly acidic) 6.6 to 7.5 (neutral) 7.6 to 7.8 (mildly alkaline) 7.9 to 8.5 (alkaline) 8.6 to 9.0 (strongly alkaline) Sun Exposure: Full Sun Sun to Partial Shade Light Shade Elevation: Naturally found between 4,500 to 5,500 feet. Habitat: Needs water so it is common to washes and is sometimes found on rocky hillsides, mesas, and plains. Miscellaneous: Flowering Photos Taken March 11, 2008. At Desert Botanical Garden Phoenix, Arizona. A good Xerioscape plant.