Four O'Clock
Mirabilis jalapa • Nyctaginaceae
🌱 Seed Category
Flower
🌍 Origin Region
Tropical South America, widely adapted globally in temperate and tropical gardens
📅 Days to Maturity
75 to 85 days from seed planting to first bloom, continuing to flower heavily until the first autumn frost.
🌡️ Hardiness Zones
USDA Hardiness Zones 7 through 10 as a tender perennial, grown as an annual in colder zones 3 through 6.
About This Seed
The seeds are roughly spherical to slightly oval, wrinkled, dark brown to black in color, and have a hard, ribbed outer coat resembling tiny hand grenades. The resulting plant is a bushy, tuberous-rooted perennial grown as an annual, featuring fragrant trumpet-shaped flowers that open in the late afternoon.
Growing Information
Growing Season
Spring planting after the last frost, can be started indoors or direct sown
Germination
Germinates in 10 to 21 days at an optimal soil temperature of 65°F to 70°F. High germination rate. Seeds benefit from a brief warm water soak or light nicking of the hard seed coat to speed up water absorption.
Planting Instructions
Plant seeds 1/4 to 1/2 inch deep, spaced 12 to 18 inches apart in well-draining garden soil with a pH between 6.0 and 7.5. Prefers moderately fertile soil amended with organic compost.
Sunlight & Water Needs
Requires full sun to partial shade (at least 6 hours of direct sunlight daily). Water moderately, allowing the soil to dry slightly between waterings; shows good drought tolerance once established.
Companion Plants
Grows well alongside marigolds, zinnias, and petunias in ornamental flower borders. Avoid planting in heavily shaded areas where competition for light is high.
Special Characteristics
Highly attractive to pollinators like hummingbirds and sphinx moths due to its evening-blooming nature. Exhibits moderate drought tolerance and grows easily from large, tuberous roots saved year after year.