Guayacan, Guaiacum coulteri.	Guayacan, Guaiacum coulteri.
Guayacan, Guaiacum coulteri.	Guayacan, Guaiacum coulteri.

Guayacán. Guaiacum coulteri, Caltrop Family ( Zygophyllaceae ), Guayacan. Also Called: Soap Bush, Guaiacum planchoni. We wish to thank Wikipedia, the free encyclopedia for some of the information on this page. We share images and information with Wikipedia. Guaiacum coulteri is a species of flowering, semi-evergreen bush or small tree; in the caltrop family, Zygophyllaceae, that is native to western Mexico and Guatemala. It is reputed to have "antidiabetic" properties, it is said to be the most effective in reducing hyperglycemia. Quick Notes: Height: 6 to 25 feet tall, and 6 to 25 feet in diameter. Fruits/Seeds: A round, shiny, reddish brown, flattened capsule 1 inch long, with 2 to 4 lobes. Flowers: Flowers 1/2 inch across, bright purple, 5 broad petals, occur either singly or in small clusters from leaf axils. Blooming Time: May to September Leaves: Opposite, pinnately compound, evergreen (can be drought or cold deciduous), 1 1/2 to 2 1/2 inches long, with 3 to 5 pairs of small, elliptical leaflets.. Found: Native of Northern Mexico in Sinaloa, Sonora, Baja Norte, & Baja California. Native of Sourthern Mexico in Chiapas, Jalisco, Mexico, Michoacan, Nayarit, Oaxaca, & Puebla. Also native to Guatemala. Elevation: Native from 800 to 2,000 feet. Hardiness: 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: 5.6 to 6.0 (acidic) 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) Sun Exposure: Full Sun Sun to Partial Shade Habitat: Alkaline, dry, well-drained/light soils. An ideal landscape plant in Arizona. Miscellaneous: Photos May 31, 2008. Phoenix Arizona Desert Botanical Garden. May 3, 2008 & September 11, 2006. Glendale Arizona Xeriscape Demonstration Garden.