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Coulter's Matilija Poppy, California Tree Poppy
Romneya coulteri 'White Cloud'

Family: Papaveraceae (pa-pav-er-AY-see-ee) (Info)
Genus: Romneya (ROM-nee-uh) (Info)
Species: coulteri (kol-TER-ee-eye) (Info)
Cultivar: White Cloud




4-6 ft. (1.2-1.8 m)


4-6 ft. (1.2-1.8 m)


USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

USDA Zone 10a: to -1.1 C (30 F)

USDA Zone 10b: to 1.7 C (35 F)

USDA Zone 11: above 4.5 C (40 F)

Sun Exposure:

Full Sun


Unknown - Tell us

Bloom Color:

White/Near White

Bloom Time:

Late Spring/Early Summer

Mid Summer

Late Summer/Early Fall





Other details:

This plant is attractive to bees, butterflies and/or birds

Drought-tolerant; suitable for xeriscaping

Average Water Needs; Water regularly; do not overwater

Soil pH requirements:

Unknown - Tell us

Patent Information:

Unknown - Tell us

Propagation Methods:

Unknown - Tell us

Seed Collecting:

Unknown - Tell us


This plant has been said to grow in the following regions:

Alameda, California

Fontana, California

Winchester, California

Gardeners' Notes:


On Apr 25, 2014, DisHammerhand from Fontana, CA wrote:

White Cloud has crinklier flowers and lusher foliage that is more silver. My plants grow larger flowers than the regular species well.

I planted White Cloud the first year I lived in my house. I stuck in in the ugly gravelly weed patch by the garage. Now there are no weeds and no patch. It is a solid thicket of Matilija Poppy. It ran under the driveway and it's coming up in the front yard right in front of my porch.

I put another on the corner with the cactus, (I live on a corner) now it's coming up all over.

It takes a few years for Matilija Poppy to start misbehaving.

If you have good drainage, water extends The bloom season -and the spread.

If you're going to have a weed problem, this is the one to have. Traffic ... read more