Lathyrus vernus

Lathyrus vernus is a perennial herbaceous plant with a bushy habit. This small bush is an early variety and long-lived in any good garden soil. It spreads rapidly from April to June, reaching a height of up to 40 cm (16in), even though its growth is slow in the first year. It flowers in soils where many plants do not flower, both in shade and in sunlight. In spring, clusters of three to six bluish-purple flowers appear, which turn almost greenish-blue when they fade. These pendulous flowers measure 1 to 2 cm (0 to 1in) long.

Its medium to dark green foliage hangs on upright stems, forming a compact display. The leaves are divided into two to four leaflets, measuring 3 to 8 cm (1 to 3in) long. They are lanceolate (shaped like a lance) and acuminate (ending in tapered points). This Lathyrus, native to continental Europe, Turkey, the Caucasus, and Siberia, is common in woodlands in mountainous regions and less widespread elsewhere.

Also known as Spring Vetchling, Lathyrus vernus is very hardy. It can tolerate temperatures as low as -20°C (-4°F).  It pairs well with narcissus and tulips as they have the same flowering period. It can also be planted with Ranunculus ficaria. Its secret weapon is having roots that absorb nitrogen from the air, allowing it to survive in poor soil.