Grow scarlet pimpernel in full sun, on soil that drains, and sow it where it will stay. Scarlet pimpernel is Anagallis, not chickweed.
Give it full sun and soil that drains — and water only until it is established
| Factor | Recommended | Avoid |
|---|---|---|
| Light | Full sun for the most flowers; light afternoon shade is fine | Do not tuck it in deep shade, where the flowers stay shut |
| Soil | Sand, loam, clay, or grit that drains | Do not plant it in a hole that stays wet |
| Water | Keep the seedbed moist until seedlings are up, then water only in a long dry spell | Do not keep established plants in soggy soil |
| Habit | A low annual mat about 8 to 10 inches tall and 12 to 24 inches wide | Do not treat it as a shrub or as a houseplant |
Scarlet pimpernel wants full sun and a hole that still drains. Keep a new seedbed moist until the seedlings are up. After that, an established plant needs water only in a long dry spell. [1] scarlet pimpernel is Anagallis arvensis, a low annual with square stems and small salmon-orange flowers. It is also listed as Lysimachia arvensis. That name is this plant, not a second kind to buy.
- Choose full sun and soil that drains. A wet pocket is the usual reason stems rot.
- Keep new seedlings watered until they are established. After that, water only in a long dry spell.
Does scarlet pimpernel need full sun?
Yes. Full sun gives you the most flowers. Light afternoon shade is fine, but deep shade keeps the flowers shut.
How often should I water scarlet pimpernel?
Keep the seedbed moist until the seedlings are up, then water only in a long dry spell.
Why do the flowers close?
The flowers open in sun and close at dusk, in cloud, and before rain. That is how the plant earned names such as shepherd's weatherglass.
Sow on the surface after frost — do not transplant
Sow after the last frost, or in late fall where you want volunteers next year. Press the seed onto the surface and cover it with no more than about 1/8 inch of soil, because the seed needs light to germinate. Do not start a tray and then move the plants. Scarlet pimpernel does not transplant well. [2]
- Wait until after frost in spring, or sow in late fall on open, draining ground.
- Sow on the surface. Cover with no more than about 1/8 inch of soil.
- Sow two or three seeds in a group, about 12 inches apart, then thin to the strongest seedling.
- Keep the surface moist until seedlings appear. That often takes 30 to 45 days at about 55 to 70°F.
- Leave the plants where they germinated. Do not lift and reset them.
- Pull extras if the mat spreads farther than you want. The plant self-sows, and frost kills the top at the end of the season.
When do I sow scarlet pimpernel?
Sow after frost in spring, or in late fall. Keep the seed on the surface, barely covered.
Can I transplant scarlet pimpernel?
No. Sow it where it will stay. The plants usually do not recover if you lift them after they are set.
Not chickweed — and not creeping jenny
A low mat with small leaves can look like common chickweed. Scarlet pimpernel has square stems and salmon-orange flowers. Common chickweed has round stems and white flowers, and a line of hairs that switches sides at each node. The underside of a pimpernel leaf often shows small dark spots. [3] Do not eat this plant. It is sometimes called poison chickweed because it can sicken livestock, pets, and people if they eat enough of it. [4] Creeping jenny is Lysimachia with round yellow flowers and a running mat that wants moisture. Salad burnet is a leafy herb, not this flower. See How to Grow Lysimachia and How to Grow Burnet.
Is scarlet pimpernel chickweed?
No. Common chickweed has round stems and white flowers. Scarlet pimpernel has square stems and salmon-orange flowers.
Is scarlet pimpernel creeping jenny?
No. Creeping jenny is Lysimachia with yellow flowers and a moist running mat. Scarlet pimpernel is Anagallis, a sunny annual.
Set scarlet pimpernel in full sun, on soil that drains, sow it on the surface after frost, leave the plants in place, and leave creeping jenny to the lysimachia bed.
FAQ
Can I grow scarlet pimpernel in a pot?
Yes, in a wide, shallow pot with a drainage hole, in full sun outdoors. Sow in the pot. Do not count on moving a seedling from a tray into the pot.
Is the blue pimpernel the same plant?
A blue form of scarlet pimpernel can show up on the same species. Blue pimpernel sold as Anagallis monelli is a tender perennial, not this catalog card. Both still want sun and soil that drains.
Is scarlet pimpernel poisonous?
Yes. Do not eat the leaves or the seed. Keep pets from grazing the mat. The plant is not a tea or a medicine crop.
Is this the same as the Scarlet Pimpernel in the novel?
No. The novel uses the flower as a sign. The garden plant is Anagallis arvensis, also called Bird's Eye on some tags.
Recommended plants
References
- [1] GardenersHQ -
https://www.gardenershq.com/Anagallis-Pimpernel.php - [2] Outsidepride -
https://www.outsidepride.com/seed/ground-cover-seed/pimpernel-seeds-scarlet.html - [3] UC IPM -
https://ipm.ucanr.edu/weeds-identification-gallery/scarlet-pimpernel/ - [4] Oregon State University -
https://horticulture.oregonstate.edu/weed/scarlet-pimpernel
More first-season notes by plant are gathered in How to Grow Guides.
Updated: Reviewed by Bosquelle Editors