Datura innoxia aka Moonflower

Datura innoxia, or downy thorn apple, belongs to the nightshade family. Kew places its native range from Texas into Mexico. Other sources describe a wider range into Central America. It grows in dry, open ground with sand or gravel. Gardeners grow this tender perennial as an annual where winters freeze. It has also spread beyond its home range. Some places class it as invasive.

Plants form bushy clumps that may spread and sprawl. Garden height reaches about 2–3.3 feet [0.6–1 metre]. Spread is often about 3.3 feet [1 metre]. NC State lists widths reaching 6 feet [1.8 metres]. Stakes can help support sprawling growth. The large, dark green leaves have an egg-like shape. Their edges form waves, and soft hairs cover their surface. Leaves can reach about 0.7 feet [0.2 metres] long. The plant sheds its leaves rather than keeping them year-round.

Large trumpet flowers point up above the leaves. Their colours include cream, pink, and pale purple. Flowers reach about 0.7 feet [0.2 metres] long. Their strong, sweet scent suits gardens viewed at night. Blooms open toward evening and can open on cloudy days. Each lasts into the next day. Flowering continues in bursts from midsummer until frost. Insects pollinate the flowers. Round, hairy fruits follow, with stiff spines across their surface. Ripe capsules split and shed seeds that persist for years.

Choose full sun and rich soil that drains well. The plant prefers moist soil but can withstand dry spells. It accepts sand, loam, clay, and chalk. It also tolerates acid, neutral, and alkaline soil. RHS gives it a UK hardiness rating of H3. NC State lists USDA zones 9–11. Use it in pots, beds, or borders. Sow seeds in spring, or start them under cover. Wait until frost risk passes before planting seedlings outdoors. It needs no routine pruning and may seed itself.

RHS reports few pest problems, but viruses can cause trouble. Keep plants away from tomatoes and potatoes to limit infection. Every part is highly poisonous when eaten. It poses risks to people, cats, and dogs. RHS also warns of skin irritation and eye exposure. Wear gloves when handling it. Historical food use does not make this plant safe to eat. It supplies scopolamine for pharmaceutical use, but is not a home remedy.