Mirabilis jalapa aka Four O'clock

Mirabilis jalapa is known as four-o'clock or marvel of Peru. It belongs to the four-o'clock family, Nyctaginaceae. Its native range runs from Mexico south to Nicaragua. This tuberous perennial grows in warm regions across the world. Gardeners also grow it as an annual in colder places. It forms an upright, bushy clump with several stems. The plant loses its leaves at the season's end.

Garden plants reach about 1.5–4 feet [0.46–1.22 metres] tall. RHS gives a smaller height range of 1.6–3.3 feet [0.5–1 metre]. Spread ranges from 1–3.3 feet [0.3–1 metre] across the sources. Older plants form large tubers that look like potatoes. Some stems become partly woody as the plant ages. Green, simple leaves grow in pairs along the stems. The leaves have no hairs, and the stems lack scent.

The scented flowers open late in the day or early evening. Cloudy weather can also bring them into bloom. Their trumpet-shaped tubes end in five lobes. Colours include white, yellow, pink, red, purple, and magenta. Some flowers show stripes or two colours. Bloom can last from June until the first frost. Hummingbirds and moths visit the flowers, and butterflies also come. The fruit has a tough outer skin and five ribs. Beds, mixed borders, and patio pots suit this plant. Its late-opening flowers add scent near patios and pools.

Give it full sun, though it can tolerate some shade. It grows in most garden soils with good drainage. Moist, humus-rich soil supports growth, with moderate watering needs. Established plants can withstand some drought. Shelter helps protect them from cold, drying winds. Sources rate it USDA zones 9–11 and RHS H3. Excess winter wet can harm tubers left outdoors. Gardeners can lift tubers before frost and store them indoors. Seeds and spring tuber division offer ways to raise plants. Aphids and slugs may attack, but serious disease is rare. It can spread by seed and become a weed.

PFAF records cooked young leaves as food for times of shortage. It also records flower dye for foods and seeds as seasoning. These reports do not remove the plant's known risks. Roots and seeds can cause stomach pain, vomiting, and diarrhoea. Handling roots may cause a skin rash. Pets may drool or vomit after eating flowers, leaves, or roots. Traditional medicine uses the roots and leaves, but toxicity remains a concern.