I someone would ask me, I would say that no garden is complete without at least one member of the ephemeral genus of Corydalis. The more common is the delightful Corydalis solida and varieties but wait until you meet the lord of the genus: Corydalis nobilis. If lucky to be able to drive you can see it in flower at Lost Horizons Nursery. It does not look quite like a Corydalis and it is hard to believe that it will become dormant in early summer.
Sometimes called Siberian Corydalis, Corydalis nobilis (Fam. Fumariaceae) was introduced in cultivation in Sweden in 1765 due to a fortunate mistake. The seeds received by Linnaeus were collected from Siberia (Altai mountain range) and believed to be of Lamprocapnos spectabilis. This wonderful Corydalis still grows happily in Carl Linnaeus’ gardens at Upsalla and at Hammarby. Unfortunately, the prediction of “a great horticultural future” for this species has not become true yet. Not being very easy to propagate might have something to do with this. It is available only from a few specialty nurseries in Europe and North America, and of course some years at Lost Horizons.
Corydalis nobilis is very hardy and will start growing quite fast in the spring achieving a 30-50 cm tall clump with juicy stems and green-blue ferny leaves. It produces lots of inflorescences, very dense, with 20-35 flowers, golden yellow with the inner petals dark violet at the top. Flowering lasts for about three weeks in April-May, and it has a spicy fragrance.
Origin: NW. Siberia, Kazakhstan, Mongolia, N. Xinjiang (China). Propagated by seed (sown immediately when ripe, otherwise the ants will run away with them to feed on the elaiosomes) or by division in the fall. Corydalis nobilis has an irregularly branched, fragile rootstock, not easy to divide; you can see it here (courtesy of Rare Books – Missouri Botanical Garden Library). It can grow in full sun or shade, but will thrive best in a place reasonable dry during the summer. A focal point in the spring garden, the Lord of the genus Corydalis never fails to attract attention and questions from the visitors.