Stylophorum diphyllum [sty-loh-FOR-um, dy-FIL-um] is a wildflower native to Eastern North America, including Ontario and the eastern United States.
It’s part of the Papaveraceae (poppy) family and often found growing in woodlands or near streams with a lot of shade from other plants.
Stylophorum diphyllum is commonly called the woods poppy or celandine poppy.
It’s known for its bright yellow flowers and the ability to spread quickly through self-seeding.
Celandine Poppy Care
Size and Growth
Celandine poppy grows from underground rhizomes and reaches up to 1.5′ feet tall.
Several pinnate leaves grow from the base of the plant.
A pair of leaves also appear at the tops of the flowering stems.
The stems contain a yellow-orange latex stain-causing substance.
It was once used as a dye for clothing but didn’t contain any known toxic effects.
Flowering and Fragrance
Stylophorum diphyllum is a spring bloomer.
- The flowers are deep yellow and have four petals and two sepals, along with many stamens.
- The flowers grow from the center of the stems between a pair of leaves.
- After the bloom, the plant produces bluish-green seed pods.
- The seeds ripen by midsummer.
- The pods then open, allowing the plant to self-seed.
Light and Temperature
Celandine poppy can’t tolerate strong sunlight. Plant in shaded areas.
It’s native to Eastern North America, covering USDA hardiness zones 4 to 9.
These zones include most of the United States.
It remains winter hardy in areas with freezing temperatures.
Watering and Feeding
- Celandine poppy plants require frequent watering.
- If the soil becomes too dry, the plant goes dormant and may eventually wilt.
- Check the soil regularly and keep it evenly moist.
- Adding a layer of mulch over the soil may help increase water retention and provide additional protection for the winter weather.
- Fertilizer isn’t necessary, but it helps.
- If using a liquid fertilizer, mix it with water and apply it once per month during the warmer months.
Soil and Transplanting
Plant celandine poppy in moist soil with organic matter.
Transplant container plants every two or three years or when the plant starts to outgrow its current container.
Crowding the roots may stunt growth and shorten the lifespan of the plant.
Grooming isn’t required.
However, trimming back the branches after flowering limits the ability of the celandine poppy to self-seed.
More from the Papaveraceae Family:
How to Propagate Stylophorum Diphyllum
Propagate Stylophorum from seed or division.
Divide clumps in spring before they bloom.
To propagate through division, use a shovel to loosen the soil around the plant.
- Gently lift the plant from the hole, using caution to avoid damaging the roots.
- Place the celandine poppy plant on its side on a clear surface, such as a porch or patio.
- Carefully loosen the dirt, but don’t shake all the dirt from the root system.
- The roots need some of the soil left in place to avoid crushing the roots when replanting.
- Use sharp gardening shears to divide the plant into multiple sections.
- Plant each section in a separate spot, spacing them at least 12″ inches apart.
Propagate from seed outdoors or indoors in the fall.
- When starting seeds indoors, use a planter tray and rich soil with a lot of organic material.
- Scatter the seeds over the soil.
- Add a light layer of soil over the seeds.
- Moisten the soil thoroughly, and the seeds should germinate within two to three months.
- After the seedlings appear, wait until they are at least 4″ inches tall before transplanting or thinning.
- The plants should be at least 12″ inches apart when thinning celandine poppy outdoors.
Seeds sown in the fall should germinate by spring and begin producing leaves and new growth.
Unfortunately, the plant won’t bloom until the following year.
Stylophorum Diphyllum Pest or Disease Problems
- Celandine poppy doesn’t suffer from any major insect or disease issues.
- The main issues to worry about include root rot and wilt.
- The plant requires moist conditions and a lot of shade.
- If the environment remains too moist, celandine poppy may develop rot.
- At the first sign of rot, try saving the plant through division.
- Follow the steps for propagating by division, in the hopes of finding a healthy rhizome to transplant.
- If the conditions remain too dry and sunny, the plant may wilt.
- The leaves may start to yellow or brown before falling off.
- Increase moisture and shade to improve the health of the plant.
- The leaves of the plant are considered toxic to animals.
- Humans are unlikely to experience serious health issues, but ingesting parts of any plant may cause mild digestive discomfort.
Suggested Celandine Poppy Uses
Plant celandine poppy in gardens or containers to bring more color to almost any area.
Avoid planting near borders or other areas where self-seeding may become a problem.
To eliminate the risk of the plant spreading through self-seeding, keep it as a container plant.