Cassia fistula known as Golden Shower and amaltas is a fast growing flowering tree. It can reaches up to 30 to 40 feet in height and 30 to 40 feet wide. The well-spaced branches are clothed with
pinnately compound leaves, with leaflets up to eight inches long and 2.5 inches wide. These leaves will
drop from the tree for a short period of time and are quickly replaced by new leaves. In summer, Golden-
Shower is decorated with thick clusters of showy yellow blooms which cover the slightly drooping
branches. The blooms are followed by the production of two-foot-long, dark brown, cylindrical seedpods
which persist on the tree throughout the winter before falling to litter the ground.
Golden-Shower tree grows well in full sun on well-drained soil. Although Golden-Shower is damaged by temperatures falling slightly below freezing, it will come back with warmer weather. Sprouts may develop along the main branches in response to this low temperature. Like some other trees, fruit may be poisonous if ingested. Pollen can cause some allergies in certain people.
Trees will require pruning when they are young to control shape, to develop a uniform crown and to create good structure. Young trees can grow asymmetrical with branches often drooping toward the ground. Staking when the tree is young and proper pruning will help develop a well-shaped and well-structured crown but do not expect it to grow like a neat “meat ball”. Trees are tolerant of urban conditions and have performed well as street and park trees.
Trees in their native forest habitat typically have one leader or trunk for several dozen feet, then trunks divide into several codominant stems toward the top of the tree. Unless properly pruned, trees in more open landscapes develop several codominant stems fairly close to the ground. These could become weak and split if structural pruning is neglected.
Plant serves as host for Cloudless sulfur (Phoebis sennae), orange-barred sulfur (Phoebis philea), and sleepy orange (Eurema nicippe) butterfly larvae.