Cassia Fistula Seeds

Identification

• Mature Cassia fistula trees are around 30 to 40 feet tall with an approximately equal spread. Their single trunks are topped by drooping branches and an irregular vase- or oval-shaped crown. The pinnately compound leaves, or leaves shaped like the palm of a hand, are composed of between 4 and 8 pairs of opposite, oval-shaped leaflets. Large clusters of bright yellow blossoms cover the tree in summer. Hanging seed pods replace the blossoms. These dark brown pods can grow as large as 2 feet in length and an inch in diameter.

Seeds

• Cassia fistula seed pods are composed of individual cells and may contain as many as 100 flat brown seeds. A sticky blackish-brown pulp surrounds each seed. You can obtain seeds for planting by purchasing them through a commercial vendor or by harvesting them from mature pods that have fallen to the ground. A hard coat surrounds these seeds, and they must be treated before planting by soaking them for 20 to 45 minutes in sulphuric acid or by puncturing the seed coat. Plant the seed directly in the ground in a location that receives full sunlight.

Caring for Cassia Fistula

• For best results, Stephen H. Brown from the University of Florida IFAS Extension recommends planting seedlings around 35 feet apart so that the trees have room to grow. Cassia fistula trees begin flowering approximately three years after the seeds germinate. They grow best in frost-free climates and are hardy in U.S. Department of Agriculture plant hardiness zones 9 through 11. These trees can adapt to a variety of well-drained soil types but may require fertilization several times a year to prevent nutrient deficiencies if they grow in soil with high pH levels.

Benefits and Liabilities

• Cassia fistula seeds are toxic if eaten, but they may also have medicinal qualities. Herbalists recommend the seeds, pulp and pods as a laxative; some tropical American cultures also use the pods to treat the symptoms of diabetes. Mature trees have a high tolerance for salinity and drought conditions. Pests such as caterpillars may feed on the leaves, while scale insects drain sap from the foliage and stems. Disease problems include leaf spot infections and root rot.