Downy thorn-apple is a velvety, gray-green plant with huge white trumpet flowers that open at dusk and stay fragrant through the night. It grows wild in Mexico, Central America, and the American Southwest, though some botanists consider the U.S. plants garden escapes. Every part of the plant is highly poisonous. It's also called pricklyburr or moonflower.
Appearance
- Appearance
- A bushy, sprawling plant 2–5 ft (0.6–1.5 m) tall with a tuberous root. Stems and leaves are covered in short, soft gray hairs.
- Leaves
- Large, oval, smooth-edged leaves. Crushed leaves smell unpleasant—some people compare the odor to rancid peanut butter.
- Flowers
- White trumpets 5–7.5 in (12–19 cm) long, sometimes tinged pink or lavender. They first point upward, then tilt down; each opens in the evening and lasts until the next afternoon.
- Flowering time
- Blooms on and off from early summer until frost.
- Fruit
- A round about 2 in (5 cm) across, covered in spines, that hangs down and splits open irregularly when ripe.
Look-alikes
Where it lives
- Typical habitats
- Roadsides
- Vacant lots
- Old fields
- Overgrazed pastures
- Range
- Wild from Mexico through Central America, and often listed as native in the Southwest from Arizona to Texas. Escaped plants now turn up well beyond that, including the mid-Atlantic states and eastern Canada, and the species has spread to Africa, Asia, Australia, and Europe.
- Preferred conditions
- Favors warm, open, sunny spots on disturbed ground with fertile soil, and tolerates both drought and waterlogged soil.
Life cycle
- Seed dispersal
- Seeds can stay alive in the soil for decades. They travel in contaminated crop seed, on farm machinery and vehicles, and plants can also regrow from root pieces.
Growing it
- Care
- Sold as an ornamental and usually grown as an annual; it survives winter outdoors only in USDA zones 9–10. Keep it away from tomatoes and potatoes, since it easily picks up nightshade viruses.
- Toxicity
- All parts contain scopolamine and related compounds. Eating any part can cause dilated pupils, dry mouth, hallucinations, a racing heart, high fever, and death, and potency varies widely from plant to plant. It is dangerous to children, pets, horses, and cattle.
Conservation
- IUCN Red List
- NENot EvaluatedNot yet assessed
- Status
- A California risk screening rated it at high risk of becoming invasive there.
Culture and stories
- Culture and stories
- The species name innoxia is Latin for "harmless"—an odd fit for such a poisonous plant. It was misspelled "inoxia" when first published in 1768, so you'll see both spellings.
- Many Native American peoples have used it in sacred ceremonies and rites of passage.
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