Romneya coulteri
Californian tree poppy
R. coulteri is a vigorous, suckering herbaceous perennial to 2m in height, with divided, grey-green leaves and poppy-like flowers 15cm in width, with crinkled, pure white petals and a boss of deep yellow stamens
Other common names
bush poppyCalifornian poppy
see morecanyon poppy
dream of the desert
giant white Californian poppy
Matilija poppy
Size
Ultimate height
1.5–2.5 metresTime to ultimate height
5–10 yearsUltimate spread
1–1.5 metresGrowing conditions
Moisture
Moist but well–drained, Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green Grey Silver | |||
|---|---|---|---|---|
| Summer | White Yellow | Green Grey Silver | ||
| Autumn | Green Grey Silver | |||
| Winter |
Position
- Full sun
Aspect
South–facing or West–facing
Exposure
ShelteredDrought resistance
Yes Hardiness
H5Botanical details
- Family
- Papaveraceae
- Native to the UK
- No
- Foliage
- Deciduous
- Habit
- Suckering
- Genus
Romneya are suckering subshrubs with pinnately lobed leaves and large white flowers in summer
- Name status
Correct
- Plant range
- California, Mexico
How to grow
Cultivation
Grow against a warm, sunny wall protected from cold winds. Mulch deeply prior to winter. They dislike transplanting but once established it can spread, so site with care
Propagation
Propagate by basal cuttings in spring, root cuttings in winter or propagate by seed sown in spring at 13°C to 16°C
Suggested planting locations and garden types
- Cottage and informal garden
- Mediterranean climate plants
- Wall side borders
Pruning
Pests
Caterpillars may be a problem
Diseases
Powdery mildews may be a problem
Get involved
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