Asarum forbesii

Asarum forbesii, also called Du Heng, is a perennial from China. It is part of the Aristolochiaceae family. Kew gives its home range as southern China's temperate zone. Plants For A Future lists these Chinese provinces within its range: Anhui, Zhejiang, Henan, Hubei, Jiangxi, Jiangsu and Sichuan. It grows in rocky ravines and damp forest valleys. Known sites lie below 2,625 feet [800 metres]. It is not native to Britain or Ireland.

This small plant grows about 0.7 feet [0.2 metres] tall. Its flowers bloom from April to May. Each flower has both male and female organs. Flies carry pollen between the flowers. The supplied species records lack clear leaf or stem details. They give no mature width or details of the fruit. RHS gives broader leaf traits for the genus. Those traits do not describe this species.

Plants For A Future says full or part shade suits it. Its garden notes favour dappled shade or a shaded edge. Those notes rule out deep shade, so the shade advice differs. The plant needs moist soil that drains well. The entry lists sand, loam and clay as suitable soils. It lists slightly acid, neutral and slightly alkaline soils too. A moist woodland bed fits its known habitat and garden use. The source does not confirm how well it withstands British cold. Its estimate draws on broader guidance for the genus.

The notes on raising plants advise sowing fresh seed in summer. Sow it in a cold frame once it is ripe. Give stored seed three weeks of cold before late-winter sowing. The source says seeds sprout in spring at about 64°F [18°C]. They may take one to four weeks, or longer, to sprout. Move young plants into their own pots when large enough to handle. Keep them in light greenhouse shade through their first winter. Plant them outside in late spring once large enough. You can also split plants in spring or autumn. Keep the split plants potted in light shade until growth is strong. Plants are slow to increase.

The records list no edible uses for this species. Plants For A Future reports root use for cough and fever. It also lists use for worms and goitre. These records of use as medicine do not prove safety or benefit. The source reports no confirmed toxic effects for this species. Its warning draws on reports about other members of the genus. Thus, this species may or may not be safe. The supplied evidence names no pests or diseases.