(Revised 24 Nov 2017)
This is a delicate and elegant class of perennials like their relative, Dicentra. The blue flower varieties are particularly precious, but they are not the easiest to grow here. I like Corydalis enough that I tolerate some of them that tend to self-sow wildly and bordering on weedy. Fortunately, they are relatively easy to weed.
Corydalis ‘Wildside Blue’
This is probably the best blue Corydalis in my garden. It is similar to Corydalis elata; vigorous and does not go summer dormant. It appears to bloom earlier and slightly darker blue than elata, but I need to observe a few years and under different exposure to be sure.
It orinated from Wildside Nursery in UK.
This is a lovely Corydalis with flowers start out an attractive reddish pink and gradually faded somewhat to a beautiful soft lilac pink colour. It flowers in early spring, but the whole plant disappears after flowering until the following spring. It is one of my most eagerly awaited flowers each spring. Although it looks better in a realatively bigger patch, I tried to divide it and spread to another area in the hope that the voles cannot destroy it in one go.
It is found in northeastern North Korea adjacent to China.
This is one of my favourite blue Corydalis because it is vigorous and one of the easiest ‘blue’ Corydalis to grow. The flower colour of the stock in cultivation appears to vary; ranging from purplish blue to blue. I have the plant for quite a few years. The purplish tone appears to vary from year to year or locations, but mostly blue.
It came from Sichuan Province of China, and the first C. elata was from plants collected on Mount Omei, and propogated by Elizabeth Strangman of Washfield Nursery in Kent, England [paghat].
Corydalis flexuosa ‘Blue Panda’
This is one of the many clones of Corydalis flexuosa. As far as ‘garden look’ goes, it is quite ‘similar’ to Corydalis elata but much smaller and weaker, and usually dies down in summer, at least in my garden. I hope the plant in my possession was correctly labelled.
It originated from a micropropagated Corydalis flexuosa from a Washington nurseryman, and was brought to UK under the cultivar name of ‘Blue Panda’.
Corydalis flexuosa ‘Purple Leaf’
It is another Corydalis flexuosa clone similar to ‘Blue Panda’, and is also known as ‘Blue Dragon’. It has a cute a little purplish patch on each leaf. It is much more vigorous and easier to grow than ‘Blue Panda’, and may not go summer dormant, or at least leaves re-emerge in the fall. My little patch is under constant threat from voles. I tried to divide and spread it in th hope of a great chance for their survival.
It was introduced from China by British botanists in 1989. (The following is an interesting excerpt from the RHS Encyclopedia of Perennials: “… their Chinese hosts drove them through woods carpeted with blue, but were relunctant to stop so that the visitors can examine them. Eventually, they were persuaded and small pieces of three different plants were packed in a moss-lined film canister. On their return, the three different pieces were distributed to three different nurseries….They were first grown under the reference numbers given by the collectors, and eventually named ‘Purple Leaf’ (CD&R528a), ‘Pere David’ (CD&R528b), and ‘China Blue’ (CD&R528c)…)
Despite its rude self-sowing habit, I put up with it because it has nice ferny foliage, is long blooming and easy going, lives in shade, and is a Corydalis. Fortunately, it is very easy to remove ‘excess’ Corydalis lutea; no stubborn invasive root or carpet sowing tiny plants.
It is native to central and western European Alps. From more recent genetic research, it is supposed to be re-classified as Pseudofumaria lutea, and Corydalis lutea is considered a synonym.
Most books talk highly of this Corydalis, but I find it sloppy and messy. It needs a fair bit of room, and I am not certain that it deserves it.
I like this much more than Corydalis lutea because the flower is white, and does not self-sow as wildly (but close). My stock came from a batch of seeds I sowed many years ago. The seeds did not germinate the first season, but I did not get around to throw the contents away. I was very surprised to find seedlings sprouted the following season. It is an important filler plant for me; both for the foliage and the flowers. I understand that it often grows on cliff and rock outcrop in its natural habitat, and naturalized on city walls of old towns. I should try to grow some like that to get a deeper flavour of its true beauty.
It is native to northwestern Balkans and northern Italy. Recent research has resulted in its re-classification as Pseudofumaria alba, and Corydalis ochroleuca is used as synonym.
Corydalis sheareri ‘Silver Septre’
This is an illusive plant in my garden. I thought I have lost it, but it re-appeared, and occasionally offered me a few blooms to surprise me. May be I have been neglecting and ignoring it too much. I like the colour of its flowers.
Corydalis sheareri is common is central and southern China. Corydalis sheareri ‘Silver Septre’ is a clone collected by Dan Hinkley in Sichuan.
Corydalis shihmienensis ‘Blackberry Wine’
Apart from a cool name, it has nice purple lilac flowers. It is similar to Corydalis taliensis in flowers and leaves and equally floppy. However, taliensis is a true perennial and self-sow wildly (almost as bad as Corydalis Lutea), and shihmienensis ‘seems to be usually annual or biennial’. That could explain my first trial a few years ago lasted two seasons. I will keep an eye on the current one which was obtained last year.
Corydalis shihmienensis is native to central Sichuan, China. (Some books suggest that it may be a hybrid of Corydalis flexuosa.)
It appears to self sow extensively in Marion Jarvie’s garden in a beautiful range of colours. My plant came from Lost Horizon and is their red form.
Corydalis taliensis (金钩如意草)
It is quite similar to Corydalis shihmienensis in flower colour and floppy habit. It self-sows quite readily, and I have to try to separate it from other less rude Corydalis by confining it to its own areas. My Corydalis reference book states that “…it does not seed spontaneously..”. It makes me wonder whether my plant is mis-identified, but looking at the image from Chinese reference seems to suggest that it is the closest.
It originated from Yunnan and Sichuan of China.
When I was really excited when I received this plant. It came with a few heavenly pale blue flowers that really enchanted me. It is a small plant intended for my ‘rock’ garden. Unfortunately, the voles have been very active under where it was planted, and destroyed before it has a chance to try our winter. I wish I can buy it again but it is no longer available anywhere.
Its origin is wide spread from Siberia to northeastern China and Korea.