Himalayan Coral Tree (Erythrina arborescens) Packet of 10 Seeds. Plant Type - Deciduous tropical shrub or small tree Hardiness - Zones 9 -11 Size - Fast grower 4 to 10 ft tall. Excellent for pot culture - easily kept any size Culture - Well drained, humus rich soil. Full to part sun. Regular water and fertilizer. Native to the Himalayas. A short shrubby Erythrina, to 10', with slightly prickly trunk and branches. Large broad leaves are often absent when flowering - the flowers are large, bright and showy. Excellent for pot culture or in the ground in zones 9 and warmer.