Plant library · Annual Flowers
Mirabilis jalapa
Four O'Clock forms a bushy, roughly 3-foot-tall plant with fragrant trumpet flowers that open late in the afternoon. Its early-summer-to-fall display gives a bed a later-day focal point rather than an all-day flower show. Use it where its evening fragrance can be noticed and where the plant’s 2½-foot spread can read as a rounded midsize mass.
Place Four O'Clock toward the middle or back of a sunny annual border, behind lower edging plants and clear of narrow circulation routes. A position beside a patio, pool, sitting area, or evening path makes the late-opening, fragrant flowers part of how the space is used after the heat of the day. Group several plants in a loose drift rather than making a tight front-of-bed line; the bushy form needs room to hold its outline.[1][2]
Set plants 2 feet apart, center to center. Each plant can finish about 2½ feet wide, so neighboring plants may knit into a broad, informal planting mass as the season advances. Keep the first row at least 18 inches back from a path or bed edge to prevent the foliage from leaning into walking space and to leave a practical reach-in zone for cleanup.
Use a full-sun position for the fullest growth and flowering. Give plants moderate water, especially while they are establishing, without turning the planting area into a persistently saturated pocket. A well-drained bed is a sound fit, so avoid placing it at the bottom of a slope or beside downspouts where water collects after rain.[1][2]
Flowers begin in early summer and continue into fall, opening in late afternoon or early evening and fading by the following morning. Plan the surrounding bed for its evening presence: leave sightlines from a porch or seating area, and avoid burying it behind taller late-season growers. The plant is annual in this planting plan, so the space becomes available again after the season ends.
Allow a little buffer around Four O'Clock in beds where volunteer seedlings would complicate the next year’s layout. It can self-sow vigorously, particularly in warm conditions, so remove unwanted seedlings early and keep it out of tightly choreographed planting patterns unless reseeding is welcome.[1]
Editorial content updated 2026-07-20.