Microtis unifolia aka Common Onion Orchid

Microtis unifolia is a small orchid that grows in the ground. It has tubers below ground. Its common name is onion-leaf orchis. It belongs to the orchid family, Orchidaceae. It lives for several years. Its native range runs from southern China to Japan and Malesia. It also spans Australasia and islands of the southern Pacific. Sources place it in warm temperate regions. They also place it in subtropical and tropical regions.

Plants reach about 0.5–1.6 feet [0.15–0.5 metres] tall. One source also gives a height of 1 foot [0.3 metres]. The small tuber spans just a few millimetres. In New Zealand, it grows on banks and in poor pasture. Records name the North, South, Stewart, and Chatham Islands. It also grows on grassy slopes and in damp, sunny meadows. In the tropics, it reaches 6,560 feet [2,000 metres] above sea level.

PFAF gives its bloom time as October to January. Each flower has both male and female organs. Insects carry pollen between the flowers. The blooms have a strong scent that is rather too sweet. This gives it some value in plant collections grown for scent. The sources give few facts on its leaves or fruit. They name garden beds as a place to grow it. Its small size makes it a low plant in these beds.

PFAF states that it accepts sun or light shade. It prefers moist soil but accepts sand, loam, or clay. Its stated pH range runs from mildly acid to mildly alkaline. PFAF lists USDA zones 8–11 but urges care about growing it. The plant can bear light frost. Only the mildest parts of Britain may suit it outdoors. Its late blooms may make a greenhouse a better choice. Few published guides explain how to grow it. Treat these limits with care.

Seeds hold little stored food, so raising them needs care. A soil fungus helps feed the young orchid as it grows. PFAF says to sow fresh seed on the surface under glass. Keep the seed compost from drying out. It suggests adding soil from around plants that have taken root. This brings in the fungus. The small tuber below ground has served as food in emergencies. The sources do not say how to prepare it. They report no known hazards. This does not prove that every use is safe. PFAF lists no known uses as medicine or for other tasks.