Scarlet pimpernel

How to recognise it

Growth habit

Low annual with stems 5–30 cm long that lie on the ground or turn upwards, often branched from the base.

Stem

Square and hairless.

Leaf

Opposite, stalkless, oval, 1–2 cm, hairless, with small black dots underneath.

Flower

Solitary on long, thin stalks in the leaf axils, about 1 cm across, with five orange-red, sometimes blue petals, a purple eye and yellow stamens with purple hairs. They close in cloudy weather.

Fruit/Seed

A round capsule that opens with a little lid and releases many tiny seeds. After flowering, the stalk bends downwards.

Confusion with

Common chickweed, which is edible, has a round stem with a single line of hairs, leaves without black dots and small white flowers. Blue pimpernel has blue flowers with narrow petals that do not overlap; the blue form of scarlet pimpernel has broader petals fringed with many tiny glands.

Flowering: June–October

Why grow it?

• A colourful field flower that blooms from June into October, in an unusual orange-red.
• To be honest: the flowers have no nectar and mostly self-pollinate, so for bees and hoverflies it is only a small extra.
• A typical plant of arable fields and vegetable gardens, at home in a cornfield-flower border with poppies and cornflowers.
• A fun plant for ‘forecasting’ the weather with children: open flowers mean sunshine.
• A piece of farming history: it has accompanied arable farming for centuries.

Scarlet pimpernel: where does it grow best?

• In the wild in arable fields, vegetable gardens and vineyards, on waste ground, verges and open patches in the dunes.
• Full sun: the flowers only open in sunshine.
• Light, warm soil: sand, loam or chalk, fairly dry to moderately moist, open and without dense vegetation.
• In the garden: a cornfield-flower border, a vegetable garden, a gravel path or the edge of a sunny terrace.

Goes well with

• Common poppy: Red above, orange-red below: the same cornfield-flower border, on the same loose soil.
• Cornflower: Blue next to the orange-red, a classic field flower for bees.
• Scented mayweed: Small white flowers with a yellow centre in the same border.
• Field pansy: Another small field plant for the front of the border.
• Corn marigold: Golden-yellow flowers on the same sunny, sandy field soil.

Scarlet pimpernel: when and how to plant it?

1. Scarlet pimpernel usually comes up by itself in the vegetable garden or on dug soil: the seed can lie in the ground for years.
2. If you want to sow it on purpose, buy seed of native origin, often as part of a cornfield-flower mix.
3. Sow in September–October or March–April on loosened, bare soil; scatter thinly and rake in lightly.
4. Lightly cultivate the soil of a cornfield-flower border every year in autumn or spring, so that the annuals can germinate again.
5. Watering is only needed in dry weather after sowing; don’t feed.
6. Don’t take plants or seed from nature reserves, or from fields without the owner’s permission.

Care

Watering

Not needed.

Feeding

Don’t: on rich soil it is overgrown by more vigorous weeds.

Weeding

In the vegetable garden, weed the plants out before they flower; the shallow roots come out easily. Wear gloves if you are weeding a lot.

Mulching

A layer of mulch on the vegetable beds stops the seeds germinating.

Cornfield-flower border

Lightly cultivate the border every year, otherwise annual field flowers disappear among grasses and perennials.

Tip: If you want to see scarlet pimpernel in flower, look on a sunny morning or around midday: when a cloud passes or later in the day, the flowers close.

Pruning and mowing

When: Not needed: it is an annual. In autumn, pull up dead plants or leave them lying.

How:

• Pull up faded plants before the seed capsules ripen if you want fewer seedlings.
• In a cornfield-flower border, simply let them self-seed.
• Don’t put pulled plants with ripe seed on a compost heap that does not heat up: the seed survives there.

Caution: Wear gloves: the sap can irritate the skin of sensitive people.

Pruning calendar and basic rules

Propagation

Seed

Scarlet pimpernel only spreads by seed. Let a few plants self-seed, or sow on bare soil in autumn or spring.

Scarlet pimpernel: how does it get through the winter?

Hardy to −15 °C: protect young plants.

• Annual: the plants die in autumn, usually after the first frost.
• The seed overwinters in the soil and can stay viable there for years.
• In mild winters, small plants that germinated in autumn sometimes survive.

Diseases and pests

• Weed in the vegetable garden: It can come up among the vegetables. Hoe in dry weather, weed before flowering and mulch the soil.
• Poisonous: Don’t eat it and don’t confuse it with chickweed. Learn to recognise both plants well before you pick wild greens.
• Closed flowers: Not a disease: in cloudy weather and in the afternoon the flowers close. Look on a sunny morning.
• Disappearing: In a border that is no longer cultivated, it gets overgrown. Lightly cultivate the soil every year.

Through the year

• March: Seedlings appear. Sow in a cornfield-flower border.
• April: Sow. Hoe the vegetable garden.
• May: The plants grow. Weed where you don’t want them.
• June: Flowering begins on sunny days.
• July: Full flower. Look at the open flowers in the morning.
• August: Flowering and ripe seed capsules.
• September: Flowering. Lightly cultivate the cornfield-flower border and sow.
• October: Last flowers. Clear dead plants.

Did you know?

• The name scarlet pimpernel became world-famous through Baroness Orczy’s 1905 novel, whose hero uses the little flower as his sign.
• The flowers close in cloudy weather and in the afternoon; in England the plant is therefore also called poor man’s weatherglass.
• The seed capsule opens with a little lid, like a pot; botanists call this kind of fruit a pyxis.