Ornamental · Ranunculaceae
Marsh Marigold
Caltha palustris
Pop it somewhere the ground stays wet to soggy, and marsh marigold brightens the water's edge before almost anything else even wakes up.
Full sun
Every 1–3 days
USDA 3–7
8–24 in · 20–61 cm
Overview
Want early color? Marsh marigold is one of spring's first big pops of gold, opening its cupped yellow flowers at the edge of ponds, streams, and boggy ground while the rest of the garden is still snoozing. It's part of the buttercup family, and you can spot the family look in those glossy petals and the rounded, heart-shaped leaves sitting underneath.
This plant really only asks for one thing, and it's not a fussy one: wet feet. It grew up in wet meadows and marshes, so it's happiest in constantly moist to wet, humus-rich soil or even a bit of shallow standing water, which makes a pond margin, bog garden, or rain garden a perfect match. Give it that and it won't ask for much else.
It's a tough, long-lived plant that laughs off brutal winters and is easy to grow, as long as the soil never dries out. After the spring show it usually eases into summer dormancy and dies back, then pops up again the next spring. Just remember the fresh plant is an irritant, so it's worth a little care around pets and kids.
Care
The short version: give it full sun to part shade and soil that stays wet to soggy all season, in rich, mucky ground by the water, and honestly there's not much to do beyond keeping it from ever drying out.
Light
Marsh marigold is fine with full sun to part shade, and it flowers best when it gets plenty of light. In hot-summer areas, a little afternoon shade really helps, since it slows the slide into summer dormancy and keeps the leaves around longer.
Water
This is the part that matters most, no question. The roots need to stay constantly moist to wet, in soaked soil or even a bit of shallow standing water, and the plant should never dry out. Let the ground dry after flowering and it'll usually drop early into summer dormancy.
Soil
Grow it in wet, humus-rich, mucky soil like you'd find at a pond edge, and it'll even handle shallow standing water. Any pH from 5.5 to 7.5 works fine, so the soil's acidity isn't really something you need to fuss over.
Temperature
Cold? No problem at all. The plant is hardy down to about -40°F (-40°C) and takes heat up to roughly 86°F (30°C), though hot summers do tend to push it into an early dormancy.
Humidity
It likes things damp, which just comes with the wet, marginal spots it prefers anyway. High humidity around the leaves suits it, so there's nothing extra to do once it's near water.
Feeding
Feeding is barely any work. As growth kicks off in spring, give it one helping of balanced fertilizer or mix in some rich compost, and that'll carry it through the season.
Pruning
There's hardly anything to cut. Snip off the spent flowers and clear away the yellowing leaves as it dies back, and just remember that summer dieback is normal and the crown will push up fresh growth next spring.
Repotting
Split and refresh clumps every 2 to 3 years, or sooner if the flowering drops off, the roots fill the pot, or the crown starts lifting above the soil. Keep any divisions wet while they settle.
Size & spacing
Plants get to about 8 to 24 inches (20 to 61 cm) tall and spread to roughly 12 to 18 inches (30 to 46 cm) across, making a tidy little mound at the water's edge.
When to plant
Marsh marigold's on an early schedule. It wakes up and flowers in early to mid spring, one of the very first things to bloom, and then it often dies back over summer. Plant it in spring or fall in wet ground, and sow seed fresh in late summer to fall.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: Sow fresh seed in late summer to fall; cold stratification improves germination
- Plant: Spring or fall, in wet soil or pond margins after frost
- Harvest: Early to mid spring (April to June), one of the earliest spring bloomers
Hardiness
USDA hardiness zones: 3–7
Temperature: down to -40°C
Troubleshooting
Marsh marigold doesn't cause much trouble, and when it does, it almost always comes back to one thing: soil that dried out. Once you can tell a normal summer nap from real trouble, you'll hardly ever need to jump in. Match up what you're seeing below before you do anything.
Plant wilts, fades, or never comes back
When a plant droops or just doesn't show up again, the reason is usually dry soil. This is a bog plant, so its roots really want to stay moist to wet, and even a short dry patch can knock it back or do it in. The fix is easy enough: move it to a pond margin, bog garden, or rain garden, water often so the soil stays soaked, and add mulch to keep that moisture from escaping.
Fix:
- Move or replant at a pond margin, bog garden, or rain garden where soil stays wet
- Water frequently to keep the soil saturated
- Mulch to retain moisture
Leaves yellow and die back in summer
Seeing yellow leaves in summer? Don't panic, because that's summer dormancy, not a sickness. Once the spring flowers are done the plant just clocks out for a while, and a dry or hot-summer spot only speeds that up. So leave it right where it is, keep the soil nice and wet, and clear off the tired leaves after the crown has settled in for its rest.
Fix:
- Leave the plant in place and let foliage die back naturally
- Keep the soil wet to prolong the foliage and reduce stress
- Tidy away yellowed leaves once they have withered
White powder or rusty spots on the leaves
A white dusty coating is usually powdery mildew, and those little orange-brown bumps are rust. Both tend to show up when the air goes still around a packed-in clump. Just pull off the spotted leaves, thin things out so a breeze can get through, and quit watering the leaves late in the day. And here's the good news: apart from those two, there's really nothing else that bothers this plant.
Fix:
- Remove and dispose of affected leaves
- Improve air circulation around the clump
- Avoid wetting foliage late in the day
Toxicity
Here's the thing to know: the whole plant is toxic when it's fresh. Being in the buttercup family, it holds protoanemonin, an irritant that gets released when the leaves or stems are crushed or chewed, and it can blister the mouth and skin and upset the stomach. That bitter, burning taste usually stops an animal from eating much, but keep the fresh plant away from pets, livestock, and kids anyway.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds · People
Cats Toxic
If a cat bites the fresh plant, it gets a mouthful of stingy sap and usually backs off in a hurry. Keep an eye out for drooling, pawing at the mouth, vomiting, and loose stool.
Dogs Toxic
A dog that chews the leaves or stems can end up drooling and skipping meals, and vomiting or diarrhea might follow. Luckily that harsh, burning taste keeps most dogs from eating much of it.
Horses Toxic
The fresh plant stings the mouth and upsets the belly, so a grazing horse hardly ever gets past one bite. And once it dries into hay? The protoanemonin breaks down and the risk is gone.
Rabbits Toxic
This one's a no for rabbits. The same protoanemonin that bothers other animals blisters a rabbit's mouth and upsets its gut, so keep the fresh plant well out of reach.
Livestock Toxic
Cattle, goats, and sheep can get blistered lips and a sore stomach from the raw plant, though the bitter taste usually stops them grazing it. Dry it into hay and it loses its bite, no problem at all.
Birds Toxic
Best to treat it as unsafe around birds. Crushing the plant lets out the same caustic compound that troubles mammals, so there's no reason to let a bird peck at it.
People Caution
Never eat any part raw. The fresh sap can blister the mouth and skin, so glove up before you cut it, though a thorough boil breaks the toxin down and the cooked young leaves and buds have been eaten for ages.
The raw plant is toxic and irritant: the same protoanemonin found in buttercups and clematis. Cooking (boiling) destroys the protoanemonin, and cooked young leaves and flower buds have historically been eaten - never eat any part raw. The sap can irritate skin, so wear gloves when handling or cutting.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
Poison Control: (800) 222-1222
Canada
Poison Centres: 1-844-764-7669
Varieties
Aside from the wild golden form, a couple of garden selections pop up now and then. These are the two worth knowing about.
'Flore Pleno' ('Multiplex')
A double-flowered type that piles on extra petal-like sepals for full, rounded golden-yellow blooms.
var. alba
A white-flowered one that trades the usual gold for clean white petals around a yellow center.
How to propagate
You can grow more marsh marigold by splitting a clump or starting from seed, and division is way faster and more reliable of the two.
DivisionEasy
Early spring or late summer after flowering · One growing season
This is the easy way to get more plants. Just lift an established clump in early spring or late summer once flowering is done, pull the crown apart into pieces, and pop each one back in. Keep the divisions soaking wet and they'll settle in over a single growing season.
SeedModerate
Sow fresh seed in late summer to fall · Several months to a year; may self-seed in suitable wet sites
Seed takes a little more waiting around. Sow it fresh in late summer to fall, because a cold winter is what wakes the seeds up and gets them sprouting. New plants need anywhere from several months to a year to get going, and if the ground stays wet, the marsh marigold will often self-seed and save you the trouble.
Myths
Marsh marigold and true cowslip are the same plant.
They both go by cowslip, so the mix-up makes sense, but they're actually in different families. Marsh marigold is Caltha palustris in the buttercup family, while true cowslip is Primula veris over with the primroses. That shared name is honestly all they have in common, so when it really matters, go by the botanical name.
Marsh marigold is a safe wild green to forage and eat.
Raw, it's a buttercup-family irritant loaded with protoanemonin, and it can blister your mouth. Only the young leaves and flower buds, boiled really well, have a history of being eaten, since cooking breaks the toxin down. No part is safe to eat raw.