What do you see when you walk through your garden or observe the neighbor’s yard? The presence and absence of different plant species tells us the climate of the area, the interests of the property owner and perhaps even a bit about their culture. However, many of us have become too comfortable with classic landscape plants, which tend to turn a yard into a green blur.
The best treatment for this ailment is exposure to new and intriguing plants — which is the goal of this column. In the past people only saw exotic plants when botanists returned from an expedition. These new species would be neatly arranged and dried in a press, waiting to be opened.
In this first installment of Branches of Botany, we will introduce a showy tree that makes a great addition to any backyard.
The Ashoka tree, which is a common name for one of the species of Saraca, adds a pop of color to any yard or garden with its clusters of vivid yellow, orange or
red flowers. Ashoka is a
Sanskrit word that translates to “without grief” or sorrow-less.
The name Ashoka is referenced in the Hindu epic The Ramayana, where two Hindu gods first meet each other in a garden of Ashoka trees. These trees are also associated with the Hindu god of love, Kamadeva. In addition to their connection to Hinduism, these trees have an illustrious heritage in the Buddhist faith. The species Saraca asoca is considered by some to be the tree that Siddhartha Gautama, the Buddha, was born under in Lumbini, which is now in Nepal.
Saraca is also used as a medicinal plant. In the Ayurvedic tradition, it was used as an astringent to cure various types of bleeding. Modern studies have shown that leaf and bark extracts also possess antimicrobial and antioxidant properties. While their connection to religion and medicine is found in the Indian subcontinent, these trees naturally occur elsewhere in Asia.
Sorrow-less trees are found throughout temperate and tropical Asia. They range from India and Sri Lanka to parts of China, Southeast Asia, Indonesia, the Philippines and New Guinea. The genus Saraca is a member of the Fabaceae, or bean, family. These trees can grow to a height of about 33 feet or remain small treelets reaching a maximum of 20 feet. They thrive in sheltered areas with full to partial sun and well-drained, fertile soil. Saraca can be grown from seed, but most seeds will not germinate. It is best propagated from cuttings, or air layers. The sorrow-less tree can be identified by its fragrant, four-petaled yellow to red flowers and its compound leaves, like that of a monkeypod but much larger. Surprisingly these trees are rarely seen in the private gardens of Hawaii.
The two species of Ashoka that are known in the islands are S. indica and S. declinata/S. thaipingensis. Scientists still debate on the true identity of the second species. They were introduced to the isles by two eminent botanists: Joseph Rock and Dr. William Hillebrand.
Saraca thaipingensis can be seen at the Ho’omaluhia Botanical Garden in Kaneohe; it’s also currently in bloom at the Harold L. Lyon Arboretum in Manoa. Even though the trees are not endemic, all Saraca in Hawaii have a low risk of becoming invasive based on the
Hawaii Pacific Weed Risk Assessment.
Keep an eye out for these fragrant, captivating trees at future arboretum plant sales. By choosing to plant one of these beautiful trees, you also aid in its conservation as many species are at risk of becoming endangered due to overharvesting.
Jesse Adams and Tim Kroessig are both botanists at the Harold L. Lyon Arboretum, where they work to catalogue, propagate and conserve the plant diversity found there.
