The Colorado (Giant) Four O'Clock is a perennial or sub-shrub native to the southwestern U.S. and Baja California. It grows 1-2 feet tall and 3-4 feet wide, with succulent green leaves and showy magenta or pink flowers that open in the evenings and close in the morning. It is drought tolerant and well-suited for dry, sunny gardens with rocky soil. The plant attracts hummingbirds and bees to its fragrant flowers and provides habitat for hawk moths. It requires full sun, low water once established, and can be propagated from seed or cuttings.

1. * Colorado (Giant) Four O’Clock – Mirabilis multiflora
(mih-RAB-ih-liss mul-tih-FLOR-uh)
Family: Nyctaginaceae (Four O’Clock Family)
Native to: Southwestern U.S. to Baja. Locally in Tehachapi & Liebre Mountains, Mojave Desert;
open, sandy hillsides & mesas in juniper & pinyon communities,
rocks & shrubs.
2500 to 6500 ft., often among
perennial/ sub-shrub
mature height: 1-2 ft. mature width: 3-4 ft.
Herbaceous perennial or sub-shrub that dies back in winter. Stems succulent, clumping to almost
vine-like. Leaves are succulent, light green and very attractive – may be sticky. Attractive. Like
others in this family all parts of the plant are toxic and should not be eaten.
Growth characteristics:
Blooms in summer – usually June/July, even August.
Flowers are a brilliant
magenta or pink – very showy against the green foliage. Flowers large (up to 2 inches), petunialike and very attractive. Fragrant flowers open in late afternoon & close in the morning. This plant
is a real surprise, particularly since it grows in dry climates.
Blooms/fruits:
Popular flowering perennial in southwestern gardens.
Often used as a
seasonal groundcover or in flower beds. Can be used with desert plants or in rock gardens. Long
roots make it great for slopes.
Uses in the garden:
Sensible substitute for: Non-native flowering perennials and annuals like petunia.
Habitat plant for large Hawk moths, which feed at dusk and are the pollinators. Bees &
hummingbirds will also visit flowers in early morning and at dusk.
Attracts:
Requirements:
Element
Sun
Soil
Water
Fertilizer
Other
Requirement
Full sun (cooler gardens) to part shade (morning sun is good).
Rocky soils best, but not picky; any local pH.
Very drought tolerant, so don’t over-water – Zone 1-2 in summer.
Not needed but light fertilizer is OK.
Management:
Prune back almost to the ground in fall.
Other than that, easy if not over-watered.
Propagation: from seed: hot water soak 48 hrs; can also nick hard seed coat
by cuttings: tip
cuttings in summer
Plant/seed sources (see list for source numbers): 1, 2, 5, 13, 16
* CA native plant but not native to Western L.A. county
6/21/10
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