Of all the numerous offspring of the prodigiously promiscuous Corydalis flexuosa, Corydalis x ‘Craigton Blue’ is surely one of the finest. It is suitably robust in the many categories that a gardener demands their plants perform in. Long flowering, almost perpetual leaf cover and unfussy about position; it’s a pretty easy going plant.

Long lost parents
The ‘x’ in Corydalis x ‘Craigton Blue’s name denotes it’s hybrid parentage. You will see it variously described as the result of a cross between Corydalis flexuosa and Corydalis elata, Corydalis cashmeriana or Corydalis omeiana. I’m going with omeiana as described by Ian Young (of SRGC bulb log fame). He’s the chap who discovered ‘Craigton Blue’ as a chance seedling in his garden, and quite a discovery it was too. It is also described as a cross between flexuosa and omeiana by Messrs. Tebbitt, Lidén and Zetterlund. I’ve not known their book to be wrong on any other subject, so I don’t suppose they are here.

Both of it’s parents originate from the higher elevations of the forests of Sichuan Province, China. As such, warm, wet summers on fertile woodland soils suit ‘Craigton Blue’ to a tee. However, it’s hybridity gives it much less particular tastes – coping with drier summers much better than either of it’s parents.
In the Garden
‘Craigton Blue’s electric blue flowers come out in spring and, on the proviso that it has a suitably moist summer, it can flower right through to the autumn. (As with many Corydalis and Dicentra, it will go dormant in a dry summer) Beneath it’s flowers lies an almost perpetual carpet of lime green foliage from which the red-tinged flower stems arise.
Where some of the herbaceous Corydalis from the rather confusing flexuosa complex of species are a little tricky to grow, depending on your specific conditions, Corydalis x ‘Craigton Blue’ is one of the more forgiving hybrids available, and also the most generous. It is a star performer here, a plant that comes highly recommended. Keep it as moist as your conditions allow during the summer, and it will reward you with a very long lived display of flowers.
What a striking blue, wish I could order some from you!
Yes, it’s quite an intense blue, especially when the flowers are freshly emerged. I know, it’s a real pain – there are some excellent bulb suppliers in the Latvia and Lithuania, but buying from them is now prohibitively expensive due to all the paperwork. Hopefully things will settle down in the future!