Polygonatum involucratum

Polygonatum involucratum is a small plant that lives for years. It belongs to the asparagus family, Asparagaceae. It grows from a rhizome, a stem below ground. It reaches about 1 foot [0.3 metres] tall. Its native range is in the temperate parts of eastern Asia. Kew lists the Russian Far East, Korea, and Japan. Plants For A Future also lists northern China. It is not native to Britain or Ireland. In Japan, it grows in mountain meadows. In China, it grows in forests and on damp, shaded slopes. These sites lie about 2,300–4,600 feet [700–1,400 metres] above sea level.

The plant blooms in May and June. Each flower has both male and female organs. Bees pollinate the flowers. The plant is self-fertile: it can set seed with its own pollen. Its seeds ripen from August through September. The supplied species account does not state the flower colour. It does not describe the fruit, leaf shape, or stem form. The RHS gives such details for the genus as a whole. These do not show the exact look of this species.

Plants For A Future lists full and partial shade as suitable. Its garden notes favour dappled shade and shaded edges over deep shade. These notes support its use in a woodland garden. It prefers moist soil that drains well. It can grow in sand, loam, or clay. The stated pH range is mildly acid to mildly alkaline. The source is unsure how well it withstands British cold. Based on its native range, the author expects it to survive outdoors. The author does not confirm a hardiness zone. The supplied evidence lists no pest or disease problems for this species.

Plants For A Future says to sow fresh seed in early autumn. Use a shaded spot in a cold greenhouse. Sow stored seed early in the year. Seeds may take time to sprout. Young plants need several years to gain size. Keep them in shade through at least their first winter. Plant them outside in late spring or early summer. Wait until expected frosts have passed. You can also divide plants in March or October.

Plants For A Future lists cooked young shoots and cooked roots as food. The roots hold starch, and the shoots can replace asparagus. Its list of edible parts also names the leaves. It gives no details on how to prepare them. It lists no known uses as medicine or for other purposes. The source reports no known cases of poisoning from this species. This does not prove that every plant part is safe.