Setaria palmifolia aka Broadleaved Bristlegrass

Setaria palmifolia, or palm grass, is in the grass family. It comes from tropical and subtropical Asia to eastern Australia. It grows in wet parts of the tropics, including open woods. It also grows by shaded paths and at thicket edges. People grow this grass for its leaves and food. It lives for more than one year.

The plant forms large clumps with thick stems that stand upright. Its form can be upright, spreading, or mound-shaped. Garden plants reach about 5–8 feet [1.5–2.5 metres] tall and wide. Some accounts give heights near 10 feet [3 metres]. The RHS says it takes two to five years to reach full size. The green leaves have deep folds. Their shape ranges from oval to lance-shaped, like a spear tip. They can reach about 1.5 feet [0.45 metres] long. Plants may keep their leaves through winter in warm places.

Thin flower stems arch above the clump of leaves. The RHS notes greenish-tan sprays of flowers in late summer. Chicago Botanic Garden lists yellow blooms from September to December. Wind carries the pollen. Gardeners grow palm grass on its own or in beds. Its large, folded leaves also suit subtropical garden schemes. The RHS lists courtyards and patios as places to grow it. It also lists pots and conservatories, or glass garden rooms.

Grow it in sun or part shade with shelter. It accepts sandy, loamy, clay, or chalk soils. Soil can be acid, neutral, or alkaline, but must drain well. Rich soil that holds some moisture suits it well. It needs a fair amount of water. Once plants take root, they can cope with drought. The RHS rates it H2 and says to protect it from freezing. Chicago Botanic Garden lists USDA zones 8–11. Outside frost-free areas, use pots or lift plants for winter. Keep them in a cool greenhouse or conservatory through winter. Divide clumps in spring. You need not prune them as a rule.

Red spider mites, caterpillars, and rust may harm the plant. It has spread from gardens and become weedy in many tropical areas. People boil or roast its seeds in place of rice. They eat the tender shoot hearts raw, steamed, or with rice. Very young plants also serve as a raw side dish. Useful Tropical Plants notes use as medicine but gives no treatment details. That source lists no known hazards. This does not prove the plant is safe.