Lathyrus aphaca aka Yellow Vetchling

Lathyrus aphaca is an annual in the pea family, Fabaceae. Its common names include yellow pea and yellow vetchling. Its native range spans Macaronesia, the Mediterranean, and central Asia. It also reaches the Indian subcontinent. The RHS lists it as native to Britain and Ireland. It grows in temperate regions, in dry, open places. Wild sites include sand, gravel, and chalk.

This scrambling plant reaches about 3 feet [0.9 metres] high. It uses tendrils to climb through nearby growth. Its leaf structure is unusual and worth a close look. The true leaves have changed into tendrils. The stipules take on the role of leaves instead. It flowers from June to August. Each flower has both male and female organs. Bees pollinate the flowers, though the plant is also self-fertile. Seeds ripen from August to September.

Grow it in full sun rather than shade. It grows easily in reasonably good garden soil. Sandy soil, loam, and clay can all suit it. Good drainage matters more than a single soil type. It accepts dry or moist ground. It tolerates mildly acid, neutral, and alkaline soil, including very alkaline conditions. It can grow in cultivated beds. Bacteria in its root nodules fix nitrogen from the air. The plant uses some of this nitrogen. Nearby plants may also gain some benefit.

Seed offers a way to raise new plants. Soak it in warm water for one day before sowing. Sow in a cold frame in early spring. Move seedlings into separate pots once large enough to handle. Plant them outside in summer. Direct sowing in mid-spring is another option. In the wild, most seeds sprout in autumn. Many of those seedlings fail to survive winter. This makes autumn germination no guarantee of plants the next year.

The seeds need caution despite their recorded food use. PFAF lists cooked, immature seeds as edible in small amounts. It gives the plant a low food-use rating. The seeds contain a toxic amino acid. Large amounts can cause lathyrism, a serious nerve disease. Fully ripe seeds may also have narcotic effects. Reported medicinal uses involve ripe seeds and flowers. These records do not establish safe home treatments. PFAF assigns a low medicinal rating and lists no other uses.