What light conditions does Caltha palustris prefer?

Marsh marigold does best with part sun to part shade, often growing along the dappled edges of wet meadows, streambanks and swamp margins.

How much water does marsh marigold need?

This forb needs consistently high moisture and grows naturally in saturated or standing water sites such as marshes, wet ditches and streambanks.

When does Caltha palustris bloom?

Marsh marigold typically flowers from April through June, with bright yellow blooms appearing early in the growing season.

What pollinators visit Caltha palustris flowers?

Bees, flies and beetles commonly visit marsh marigold flowers for pollen and nectar in spring.

Is Cowflock toxic to cats?

Yes. Cowflock is listed as toxic to cats by the Cornell University Poisonous Plants Database (aspca.org). If your cat has been exposed, call the ASPCA Animal Poison Control Center at (888) 426-4435.

Is Cowflock toxic to livestock?

The USDA PLANTS Database does not flag Cowflock as toxic to livestock.

Is Cowflock HOA-friendly?

Cowflock takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.

Cowflock

Name: Pollinator Patch
Author: Pollinator Patch

Caltha palustris

Last reviewed: August 2026

Caltha palustris, or marsh marigold, produces bright yellow flowers from April through June in wet meadows, streambanks and swamps, and grows best in consistently moist to wet soil with part sun to part shade.

Toxicity unknown

Cowflock (Caltha palustris) is not listed by the ASPCA Animal Poison Control Center (opens in new tab) or the other sources we check, so we have no verdict for it either way. Absence from those lists is not a clearance. If your pet shows symptoms after eating any plant, call the ASPCA at (888) 426-4435.

The USDA PLANTS Database (opens in new tab) does not flag Cowflock as toxic to livestock.

Light

part shade

Water

high

Size

8"–24" H × 12"–24" W

Bloom

Apr, May, Jun

Native to

CT, DE, IA, IL and 26 more states

Pollinators

bees, flies, beetles

Deer

Resistant (per Prairie Moon Nursery)

Before you buy

Your city may pay you to plant this

Cities and water utilities offer rebates for replacing lawn with native and water-wise plants. We track 452 programs across 44 states, each with a link to the provider and the date we last checked it.

Find rebates in your area

Marsh marigold is a cheerful spring wildflower that produces bright yellow buttercup-like blooms from April through June. This low-growing perennial thrives in consistently moist to wet soils and partial shade, making it perfect for rain gardens or boggy areas. The glossy heart-shaped leaves emerge early in spring and may go dormant during hot, dry summer periods.

Growing Cowflock

Grow Cowflock in part shade and high water. Mature plants reach 8 to 24 inches tall and spread 12 to 24 inches wide. Expect low maintenance to keep it looking intentional in a front yard.

In an HOA neighborhood

Cowflock takes more care to keep looking intentional in a front yard. Maintenance level: low. Consider it for backyard or mid-zone beds rather than the street edge.

Works well in: backyard only.

Goes completely dormant in summer leaving bare spots
Requires consistently wet soil which may look swampy
Wild wetland appearance doesn't suit formal landscapes

Wildlife value

The early spring flowers provide crucial nectar for bees, flies, and beetles when few other plants are blooming. Seeds may attract waterfowl and other wildlife in wetland settings.

Common questions

What light conditions does Caltha palustris prefer?: Marsh marigold does best with part sun to part shade, often growing along the dappled edges of wet meadows, streambanks and swamp margins.
How much water does marsh marigold need?: This forb needs consistently high moisture and grows naturally in saturated or standing water sites such as marshes, wet ditches and streambanks.
When does Caltha palustris bloom?: Marsh marigold typically flowers from April through June, with bright yellow blooms appearing early in the growing season.
What pollinators visit Caltha palustris flowers?: Bees, flies and beetles commonly visit marsh marigold flowers for pollen and nectar in spring.
Is Cowflock toxic to cats?: Yes. Cowflock is listed as toxic to cats by the Cornell University Poisonous Plants Database (aspca.org). If your cat has been exposed, call the ASPCA Animal Poison Control Center at (888) 426-4435.
Is Cowflock toxic to livestock?: The USDA PLANTS Database does not flag Cowflock as toxic to livestock.
Is Cowflock HOA-friendly?: Cowflock takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.

These answers were drafted with an AI model from this plant's data. Verify care details with a local expert.

Native range data from the World Checklist of Vascular Plants (Kew). Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.

If something looks wrong

Common plant problems, and what to check first

These come up on almost any plant. Each guide lists the likely causes in the order they are worth ruling out, with one thing to check before you act on any of them, and links to the source it came from.

See all plant problem guides

Ready to grow Cowflock? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.

Add this plant to your garden

iPhone app Android app

Planning a bed around it? Start a free plan with this plant

Not sure where to start? Take the 2-minute yard quiz