Overview
Caltha palustris 'Multiplex' is a perennial in the genus Caltha, part of the Ranunculaceae family. It typically grows around 0.3 m tall. Caltha palustris 'Multiplex' grows best in full sun, and tolerates most soils. Its UK hardiness is rated H7.
About the genus
Caltha is a genus of rhizomatous perennial flowering plants in the family Ranunculaceae, to which ten species have been assigned. They occur in moist environments in temperate and cold regions of both the Northern and Southern Hemispheres. Their leaves are generally heart-shaped or kidney-shaped, or are characteristically diplophyllous.
Wikipedia contributors, "Caltha", CC BY-SA 4.0 — Caltha
In the garden
Caltha palustris 'Multiplex' belongs to the buttercup family (Ranunculaceae) and is cultivated as a perennial for early-season flowering in wet situations. It stays compact, reaching roughly 0.3 m, and is valued where permanently moist soil is available. Choose a sunny spot where water does not dry out; the cultivar tolerates sandy, loamy or clay textures provided the soil remains wet. In the UK it carries an H7 rating, meaning it is fully hardy through typical British winters (USDA zones 3–7 give an additional reference for colder climates). Plant crowns at the same level they grew at in the nursery and keep the root zone consistently moist while the plant establishes. Siting options include pond margins, damp borders and any area that remains seasonally or permanently wet. The plant's compact habit makes it useful for edging shallow water or anchoring the front of a wet planting. Expect flowering in the UK from March to May, when the clump produces its spring display and helps mark the start of the season for waterside planting.
Growing conditions
Best soil and position for Caltha
- Sunlight
- Full sun
- Soil type
- Sandy, Loamy, Clay
- Soil moisture
- Wet
- UK hardiness
- H7
Plant details
Caltha palustris 'Multiplex' size, habit and characteristics
- Plant type
- Perennial
- Height
- 0.3 m
Frequently asked questions
Where is the best place to plant Caltha palustris 'Multiplex'?
Caltha palustris 'Multiplex' prefers full sun.
What soil does Caltha palustris 'Multiplex' need?
Caltha palustris 'Multiplex' is adaptable and grows happily in most soil types, including sandy, loamy and clay. Aim for soil that stays wet.
How big does Caltha palustris 'Multiplex' grow?
Caltha palustris 'Multiplex' reaches a height of 0.3 m.
Is Caltha palustris 'Multiplex' hardy in the UK?
Caltha palustris 'Multiplex' has an RHS hardiness rating of H7, meaning it is fully hardy throughout the UK, tolerating temperatures below -20°C.
From the Fenn Plants journal
- Notes on DaffodilsWhen to plant daffodil bulbs in the UK, how deep, how to naturalise them in grass, why daffodils stop flowering (“blindness”), and why you should never mix cut daffodils with other flowers.
- Keeping Your NerveHow to garden through a heatwave — the best time to water, why deep soaks beat daily sprinkles, caring for pots and vulnerable plants, and why you can let the lawn go brown.
- Made to LastHow to clean, store and protect garden pots and planters — the frost-proof vs frost-resistant difference, winter care for terracotta and ceramic, and how to reuse a broken pot.
More in the Caltha genus
- Caltha leptosepalawhite-flowered marsh marigold
- Caltha minorKingcup
- Caltha palustrismarsh marigold
- Caltha palustris 'Alba'white marsh marigold
- Caltha palustris 'Flore Pleno'Marsh Marigold 'Flore Pleno'
- Caltha polypetalagiant marsh marigold
