These are herbaceous plants, tall and short, that have fleshy roots, quickly spreading to give good clumps of flowering stems. To multiply the plants, lift the roots every few years and simply mix them with more compost and spread them around - there is no need to plant individual pieces. The flowers are the usual characteristics shape, in many varieties in shades of blue.

Corydalis flexuosa 'China Blue' is a form of a species that was a great introduction in the 1990's. I has delicate, pale olive-green foliage growing through the winter, after a dormant season in late summer. Then in spring the stems are topped with the distinctive clear sky-blue flowers, over a long flowering period. It will soon form a good patch, which can be split to provide a lovely ground cover between shrubs.