Marsh marigold (Caltha palustris), also known as caltha cowslip, is not really a marigold at all. It's actually a member of the buttercup family (Ranunculaceae). The marsh marigold has no petals. Instead, each cluster of flowers is made of five to nine sepals, which resemble petals, surrounding many stamens and pistils. Waxy deciduous foliage is rich green and each leaf is heart-shaped, kidney-shaped, or rounded with two lobes. Sow marsh marigold seeds in the late fall or early spring.
Calling to the shape of these petite 1 1/2-inch yellow blooms, caltha means “cup” coming from the Greek kalathos. Alluding to the ideal conditions for this flower to be planted, palustris means boggy or marshy. Other names are marsh cup or cup of the marsh.
Its growth habit is compact and mounding, the height ranging from 1- to 3-feet tall. For its dynamic purpose, this fast-growing rhizomatous herbaceous perennial is known as both an herb and a wildflower. Watch these vibrant perennials spread every spring, attracting the first birds, butterflies, and hummingbirds of the season.
|Botanical Name||Caltha palustris|
|Common Names||Marsh marigold, cowslip, caltha cowslips, cowflock; in Great Britain it is known as mayflower, may blobs, mollyblobs, pollyblobs, horse blob, water blobs, water bubbles, gollins, and the publican|
|Plant Type||Perennial, herb, wildflower|
|Mature Size||1–3 ft. tall, 1–1.5 ft. wide|
|Sun Exposure||Partial, shade|
|Soil Type||Loamy, moist|
|Soil pH||Acidic (6.8)|
|Hardiness Zones||3–7 (USDA)|
|Native Area||North America|
|Toxicity||Toxic to humans and pets|
Marsh Marigold Care
Marsh marigolds can be planted alongside other bodies of water such as streams, and they are often the first pond plants to bloom in early spring. These low-maintenance buttercup blossoms come up from April to June.
Marsh marigold is pretty hardy, and pests don't bother it much. Occasionally, it suffers from fungal diseases like powdery mildew and rust. These can be remedied with fungicides or milk spray.
This perennial will bloom consistently in part sun to full shade, an unusual feature as most flowering plants for water gardens prefer full sun. Establish in a south-facing or west-facing direction for best results.
Find an especially shady afternoon spot in zones 6-7, as being protected from extremely high temperatures will welcome the plant to bloom into summer and maintain healthy foliage.
Give this plant a rich, moist, or boggy soil that is damp to fully submerged in water. If planting in a rain garden, situate it near the center of the lowest spot.
Overall, plant in slow-draining areas. Adding a glorious yellow aesthetic to the edges of a pond or between the rocks near waterfalls, the marsh marigold is native to marshes, swamps, stream margins, and wet meadows in Newfoundland and Alaska south to Nebraska, Tennessee, and North Carolina. Still, they can survive drought by going dormant and returning the following year.
Temperature and Humidity
Plant marsh marigold in any moist or boggy area like the woodlands, a rain garden, or near a body of water.
Where summers are very hot, or in areas of direct sunlight, the marsh marigold may go dormant after blooming. Expect the foliage to wilt and die, and look forward to the following spring’s show.
Marsh marigolds don't need much in the way of fertilizer, but if you insist, fertilize both before new growth and before the first frost with an all-purpose fertilizer.
Propagating Marsh Marigold
Root division is a good way to propagate marsh marigold. Wearing a glove to protect your skin from toxins in this plant, divide in early spring when foliage emerges. Replant immediately and water roots well.
How to Grow Marsh Marigold From Seed
Collect seeds off the plant towards the end of its bloom period and sow them when they ripen. Do not let them dry out. Start store-bought seeds in spring.
It may take about three years for seed-started marsh marigolds to mature and start blooming. It will be well worth the wait for these splendid wildflowers to cheerfully welcome many spring seasons to come.