Caltha palustris

Caltha palustris: Buttercup Gold for Boggy Ground

Marsh Marigold sees your soggy, squelchy low spot and says YOU HAD ME AT MUD. Glossy golden cups in early spring, shiny round leaves and native credentials. Wet feet? This plant calls that a spa day.

Plant Characteristics:

• Botanical Name: Caltha palustris
• Common Name: Marsh Marigold (also called Kingcup)
• Height: 30–45 cm (12–18 in)
• Spread: 30–45 cm (12–18 in)
• Flowers: Glossy, golden yellow, cup-shaped flowers about 2.5–4 cm (1–1.5 in) across
• Bloom Time: Early to mid spring (April to May)
• Foliage: Shiny, dark green, rounded to heart-shaped leaves in a low clump
• Features: Thrives in wet soil

Where to Plant: Plant it at the edge of a pond or stream, in a rain garden, along a wet ditch or in any low spot that stays damp in spring. It brings some of the first real colour of the year to those places. The leaves often yellow and die back by midsummer, especially in heat, so place it where later-filling neighbours can cover the gap.

Companion Plants: Iris 'Butter and Sugar' carries on the yellow theme with yellow and white flowers in May and June. Monarda punctata follows with its unusual spotted blooms in June and July. At the back, Eupatorium maculatum grows 120 to 180 cm tall with pink heads from July to September. All three cope well with the damp soil that marsh marigold loves.

Plant Care: Plant it in full sun to part sun, in rich soil that stays constantly moist to wet. It will also grow in very shallow water at a pond's edge. The one thing it won't forgive is drying out in spring. Summer dormancy is normal, so don't panic when the leaves disappear. Simply tidy away the yellowed foliage. Divide crowded clumps after flowering or in early fall. All parts of the plant are poisonous if eaten raw, and the sap can irritate skin. Wear gloves when dividing, and plant it away from where pets or small children like to graze.

History: Marsh marigold grows wild across the cool, temperate parts of the Northern Hemisphere, including wetlands, wet woods and stream banks throughout much of Ontario and Quebec. Caltha comes from the Greek word for a goblet, describing the flower's shape, and palustris is Latin for "of the marsh."

Final Thoughts: Feed the earliest pollinators, brighten a pond edge and finally stop apologizing for the swamp. THE SWAMP IS A FEATURE NOW.