Caltha polypetala Hochst. ex Lorent
giant marsh marigold
A vigorous marginal aquatic perennial, up to 60cm high and 90cm wide, spreading by rooting stems across ground or across water. It has rounded green leaves, the basal leaves up to 10cm across, the stem leaves fewer and smaller, and shining, bright golden yellow flowers, up to 5cm across, from early spring to summer
Size
Ultimate height
0.5–1 metresTime to ultimate height
2–5 yearsUltimate spread
0.5–1 metresGrowing conditions
Moisture
Poorly–drainedpH
Acid, Alkaline, NeutralColour & scent
Stem | Flower | Foliage | Fruit | |
Spring | Gold Yellow | Green | ||
---|---|---|---|---|
Summer | Gold Yellow | Green | ||
Autumn | Green | |||
Winter |
Position
- Full sun
Aspect
South–facing or West–facing or East–facing
Exposure
Exposed or Sheltered Hardiness
H7Botanical details
- Family
- Ranunculaceae
- Native to the UK
- No
- Foliage
- Deciduous
- Habit
- Clump forming
- Genus
Caltha are rhizomatous herbaceous perennials with simple, usually heart-shaped leaves and cup-shaped yellow or white flowers in early spring
- Name status
Correct
- Plant range
- Temp N Hemisphere
How to grow
Cultivation
Plant from spring to autumn in full sun, in deep, rich organic soil, at the water's edge or in shallow water up to 15cm deep; mulch annually to conserve moisture. See pond plants and bog gardens for further advice
Propagation
Propagate by seed, sown fresh in late summer in a cold frame, making sure that the compost does not dry out, or by division in spring
Suggested planting locations and garden types
- Cottage and informal garden
- Low Maintenance
Pruning
No pruning required, though the stems may be cut back after flowering
Pests
Generally pest-free
Diseases
May be affected by powdery mildews and rust diseases
Get involved
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