In the Ninomaru grove of the East Gardens of the Imperial Palace, just south of Palaceside Building in Takebashi, Tokyo, kinran and ginran orchids bloom delicately. Under tall trees pushing out new shoots for more sun, yellow kinran and white ginran about 30–40 cm high quietly announce spring.
Kinran and ginran were once common in domestic woodlands but declined sharply from about 20 years ago; in 1997 (Heisei 9) they were listed as Category II endangered in the Environment Ministry Red Data Book. Woodland loss to development and over-collecting during a wild-orchid boom are causes; they are also extremely hard to grow in home gardens or planters.
Artificial cultivation is difficult because kinran, unlike many orchids, obtains nitrogen and carbon through symbiotic fungi on tree roots; if that relationship breaks, healthy growth fails. Botanists report kinran gets about 49% of nitrogen and 40% of carbon from symbionts; ginran depends on fungi for 48–59% of carbon and over 90% of nitrogen.
Thus kinran dug alone usually dies within a few years. Building symbiosis among trees, fungi, and kinran seems possible, but if the environment changes, fungi may not survive; artificial fungal culture is also hard — no established method for symbiotic cultivation.
If you find kinran or ginran elsewhere, admire them quietly and leave them be — "kinran and ginran belong in the wild," as the saying goes.