perennialN. America Native

Colorado Four O'Clock

The Story

Plant Bio

Mirabilis multiflora is a sprawling, mounding herbaceous perennial native to the southwestern United States and northern Mexico, forming stout clumps from a massive underground tuberous root system. The repeatedly forked stems carry thick, fleshy, blue-green leaves and produce clusters of magenta flowers that open in the late afternoon and close by mid-morning.

This species is distinguished by its exceptionally deep, carrot-like tuberous root that provides extreme drought tolerance once established. The flowers are held in a unique bell-shaped, five-lobed fused structure in the upper leaf axils, attracting nocturnal pollinators like hawkmoths.

Uses & Benefits:

Produces a dense mound of dark blue-green foliage covered in vibrant magenta flowers that open in the late afternoon.

Stabilizes dry, rocky slopes and thrives in lean soils where other perennials fail.

Provides nectar for nocturnal hawkmoths, native bees, and hummingbirds.

Essentials

At a Glance

Plant Type

Perennial

Height

31"

Width

71"

Light

Full Sun, Partial Sun

Zones

5, 6, 7, 8, 9

Water

Low

Humidity

Low

Lifespan

Perennial

Native To

Southwestern United States and Northern Mexico

Toxicity

Low toxicity

Bloom period

Spring – Autumn

In flower about 9 months of the year

Planting

How to Grow

Select a planting site in full sun to partial shade with exceptionally sharp, fast-draining sandy or rocky soil.
Dig a hole twice the width of the root ball and set the young plant at the same depth it was growing in the container.
Water sparingly during the first growing season to encourage the taproot to grow deep into the soil profile.
Refrain from adding organic soil amendments or fertilizers, which cause weak, sprawling growth and crown rot.

Pro Tip

Avoid transplanting established specimens, as the massive, deep tuberous root system resents disturbance and will fail to re-establish if severed.

Keep It Thriving

Care Guide

Do

Plant in lean, mineral-rich soils with high drainage capacity.
Cut dead stems back to ground level in late fall after frost-induced dormancy.
Provide full sun exposure to maintain a compact, mounding growth habit.

Don't

Do not overwater or plant in heavy, waterlogged soils, which rot the tuberous root.
Do not fertilize, as excess nutrients lead to weak, non-flowering stems.
Do not attempt to transplant or divide mature, established clumps.

Seasonal Care Calendar

Task	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Pest Check
Plant
Propagate
Prune

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

Rock gardensXeriscapesSlopes and banksNative plant gardens

Companion Plants

Bouteloua gracilis Sphaeralcea ambigua Salvia dorrii

Multiply

Propagation Methods

Good to Know

Common Questions

Colorado Four O'Clock questions

What zones can Colorado Four O'Clock grow in?

Colorado Four O'Clock is hardy in USDA Zones 5–9. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

Is Colorado Four O'Clock deer resistant?

Yes — Colorado Four O'Clock is rated deer-resistant. Deer typically pass it over, though extreme hunger can override any plant's defenses.

When does Colorado Four O'Clock bloom?

Colorado Four O'Clock typically blooms in spring through autumn. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does Colorado Four O'Clock need full sun?

Colorado Four O'Clock does best in full sun to part shade. In hot climates, afternoon shade keeps blooms fresher longer.

Is Colorado Four O'Clock drought tolerant?

Yes — once established (usually after the first full season), Colorado Four O'Clock handles dry spells with minimal watering. Water deeply its first year to build the root system that makes that possible.