Horticulture/Corydalis lutea

Corydalis lutea (Yellow Corydalis) is a low-growing herbaceous plant native to the southern foothills of the south-western and central Alps of Italy and Switzerland, but widely introduced elsewhere.

Description
Yellow Corydalis grows to 30–38 cm (12–15 in) tall and its grey-green foliage is attractive from spring until autumn. The 2 cm (¾ in) flowers are borne above the leaves from spring until mid-summer and sometimes later. The species often grows wild in cracks in old walls where drainage is excellent.

Growing Conditions
Yellow Corydalis grows in USDA Hardiness Zones 5 to 10 (average annual minimum temperature –29 °C or above); it does best in light shade, but will tolerate both full sun and deep shade. Excellent drainage is vital and the soil should be liberally supplemented with peat moss or leaf mould.