- Name also: Key Flower, Key of Heaven, Lady’s Keys, Firy Cups, Petty Mulleins, Crewel, Buckles, Paigle.
- Family: Primrose Family– Primulaceae
- Growing form: Perennial herb. Rootstock short, erect–oblique, scaly, many-rooted.
- Height: 15–30 cm (6–12 in.). Stem leafless, hairy scape.
- Flower: Corolla regular, funnel-shaped, bright yellow and orange-spotted, 8–15 mm (0.32–0.6 in.) wide, fused, narrow-tubed, 5-lobed, lobes with notched tips. Calyx narrowly campanulate, bristly, yellowish-greenish, lobes short-tapered, with tips. Stamens 5. Pistil a fused carpel. Inflorescence a dense, one-sided, 4–30-flowered umbel terminating scape.
- Leaves: In rosette; stalk winged, shorter than crinkly blade. Blade elongated ovate with blunt or cordate base, tip rounded, margin unevenly toothed, sparsely haired on top, underside densely haired especially when young.
- Fruit: Elongated, ovalish, 5-valved, 11–15 mm (0.44–0.6 in.) long capsule. Seeds flat, dark and granular.
- Habitat: Broad-leaved forests, coppices, rich sloping meadows, banks. Also ornamental and an escape from cultivation.
- Flowering time: May–June.
Cowslip’s scientific name, meaning ’the first little one of spring’, refers to the plant’s early flowering time, and in many languages, e.g. Norwegian and Swedish, its colloquial name refers to a set of keys. (English common names include key flower, key of heaven snd lady’s keys.) This is probably based on the appearance of the inflorescence, which resembles a medieval bunch of keys. According to the classic version of the tale, Virgin Mary or Saint Peter dropped the golden keys to heaven and either an angel or a high-flying bird like an eagle, hawk or skylark returned them to their owner. Cowslip then grew with its golden yellow flowers where the keys fell to honour the event.
Cowslip is a versatile healing plant and its fragrant root has been used as an expectorant and a diuretic. Its flower makes good tea and cowslip wine, and the young leaves can be eaten in salads. Cowslip is however the only poisonous member of the Primrose family, so it is not recommended to use it at home, and it is so rare on mainland Finland that it should be left alone in any case. The best chance of finding it is on the south-western archipelago and coppices on the Åland Islands in the springtime. Cowslip is the national flower of the Åland Islands.
Cowslip can be easily mixed up with oxlip (P. elatior), but the latter has a tighter calyx (cowslip has a looser ‘collar’). Another differentiating factor is the form of the leaves: the widest part of cowslip’s ovate leaf blades are the base, while oxlip’s blades are widest in the middle.