Narrow-leaved Everlasting Pea
- Name also: Flat Pea (USA)
- Family: Pea Family – Fabaceae (Leguminosae)
- Growing form: Perennial herb.
- Height: 50–180 cm (20–70 in.). Stem limp, flat, widely winged, glabrous.
- Flower: Corolla zygomorphic, red, 13–20 mm (0.52–0.8 in.) long, Petals 5; the upstanding the ‘standard’, the lateral two the ‘wings’, the lower two united to form the ‘keel’, overall shape of corolla being butterfly-like. Calyx 5-lobed. Stamens 10. A single carpel. Inflorescence long-stalked, 3–10-flowered raceme.
- Leaves: Alternate, stalked, stipulate. Leaf-stalks narrowly winged. Blade pinnate, 1-pairs, terminal leaflet modified into a tendril. Leaflets lanceolate–narrowly ovate, 5–15 cm (2–6 in.) long, with entire margins. Stipules narrower than stem.
- Fruit: 40–70 mm (1.6–2.8 in.) long, brown, 5–15-seeded (pod) legume.
- Habitat: Rich hillside forests, forest margins, hedgerows, roadsides and embankments, waste ground.
- Flowering time: July–August.
Narrow-leaved everlasting pea is one of the most handsome pea plants. Its 2-metre (6.5 feet) stem lies on the ground or climbs up low trees and bushes and trees’ lower branches. It uses its prehensile organs to climb, and it has more tendrils than its other Finnish relatives. Both the terminal leaflet and uppermost pair of leaflets have evolved into tendrils, so there is only one pair of leaflets left – and in extreme situations there are only tendril-like branches.
Narrow-leaved everlasting pea’s ornamental flowers and special stem structure easily catch the eye of even casual passers-by. The species favours fairly abundant nutrition, light and heat in sparse broad-leaved hillside forests and dry hillside meadows, where it looks exotically southern. The species looks like its close southern European relative sweet pea (L. odoratus), which is a common sight in Finnish gardens. It is grown as an ornamental, but it sometimes escapes into the wild.