Strongylodon macrobotrys, commonly known as the jade vine, emerald vine, or turquoise jade vine, is a leguminous vine endemic to the Philippines. It is a popular ornamental plant known for its cascading clusters of vibrant turquoise or greenish-blue claw-shaped flowers. Cultivating jade vine requires a tropical environment, making it a popular choice in botanical gardens and conservatories. The plant's striking appearance and limited distribution contribute to its allure among plant enthusiasts worldwide.

Origins

Strongylodon macrobotrys was first recorded by American explorers in 1841. Specimens from the plant were collected from the jungled slopes of Mount Makiling, on the Philippines’ Luzon Island, by members of the United States Exploring Expedition. The plant was described by the Harvard-based botanist Asa Gray, who also described thousands of other plants brought back by the multi-ship American expedition. Plants were collected from various countries including Honolulu and Antarctica. Gray had disagreed with Lt. Charles Wilkes, the U.S. Navy officer who had led the expedition and elected not to join the voyage itself. The expedition involved several violent altercations with indigenous populations. Wilkes was court-martialed at the end of the expedition but was acquitted.

Its species epithet macrobotrys means “long grape cluster”, from the Greek makros "long" and botrys "bunch of grapes", referring to the fruit; the genus name derives from strongylos "round", and odous "tooth", referring to the rounded teeth of the calyx.

Description

It has thick stems up to 2 cm in diameter, which it uses to crawl up tall trees to reach sunlight. Its stems can reach up to 18 m in length. The vine entwines itself through its host's trunk and branches. Like kudzu, which also belongs to the same subfamily, jade vine can completely smother dead, dying or severely damaged trees.

Its pale green foliage spreads over the canopy and is arranged alternately. Each leaf consists of three oblong leaflets with mucronate tips, the middle leaflet is the largest.

Their bright coloration is an example of copigmentation, a result of the presence of malvin (an anthocyanin) and saponarin (a flavone glucoside) in the ratio 1:9. Under the alkaline conditions (pH 7.9) found in the sap of the epidermal cells, this combination produced a pink pigmentation; the pH of the colorless inner floral tissue was found to be lower, at pH 5.6. Experiments showed that saponarin produced a strong yellow colouring in slightly alkaline conditions, resulting in the greenish tone of the flower.

Habitat and pollinators

The plant grows beside streams in damp forests, or in ravines.

There are several other species of Strongylodon, but the superficially similar red jade vine, Mucuna bennettii, is a species belonging to a different genus, Mucuna.

It seems to be endemic to the Philippines and is usually found in forests. Propagation has always been difficult. It is considered an endangered species due to the destruction of its habitat and the decrease of its natural pollinators. There seems to be a method of marcotting through mature woody stems. It is best planted in ground near a water source, but not inundated. eat them as vegetables in a similar manner as katurai.

Pests and diseases

Although well known in other Fabaceae, including soybeans, the Soybean mosaic virus has only recently been found in S. macrobotrys in Brazil (University of São Paulo, Piracicaba, São Paulo state).

  • Strongylodon macrobotrys A. Gray - inflorescence, stamen, pistil, ovary Images - Flavon's Wild herb and Alpine plants