Maranta arundinacea aka Arrowroot

Maranta arundinacea, or arrowroot, belongs to the Marantaceae family. This upright herb lives for more than one year. Its native range runs from Mexico into tropical South America. It grows on damp forest floors and in brighter clearings. Growers raise it across the tropics for its starchy rhizomes. These underground stems supply the food starch called arrowroot.

Garden plants reach about 4–5 feet [1.2–1.52 metres] tall. NC State lists heights and widths of 1–5 feet [0.3–1.52 metres]. The green stems have a reed-like form and no scent. Smooth green leaves grow in an alternate pattern. Each narrow, oval leaf tapers toward both ends. Leaves exceed 0.5 feet [0.15 metres] long. Their widths span 0.25–0.5 feet [0.08–0.15 metres]. The roots lie near the surface, while rhizomes reach deeper.

Small white flowers appear in spring and summer. They grow in pairs on thin stalks within panicles. Each flower has a curved tube and uneven petals. Two larger lower petals sit beneath a fan of upper petals. The plant draws butterflies and feeds several moth and skipper larvae. NC State reports no major pest or disease problems. It also notes that many fungi and bacteria use the plant.

Arrowroot grows at a moderate rate and needs little upkeep. It suits moist beds, pond edges, and stream banks. Partial shade suits it, though it also grows in sun. Give it fertile soil that stays moist but drains well. It grows in sand, loam, or clay and tolerates brief flooding. Loose soil helps rhizomes grow and makes harvest easier. Its preferred soil pH is 5.5–6.5. Best growth occurs at 73–84°F [23–29°C]. NC State places it in USDA zones 10–12. Dormant rhizomes can survive temperatures near 41°F [5°C]. Gardeners also grow it in pots in cooler climates.

Arrowroot serves as ground cover and works in mass plantings. It also fits edible gardens. Its rhizomes mature about ten to twelve months after planting. People eat the underground parts raw or cooked. The starch thickens soups and sauces and goes into baked foods. It also serves in face powders and some glues. Traditional uses include digestive remedies and poultices for wounds. These records describe past use, not proof of medical benefit. Useful Tropical Plants lists no known hazards.