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Corydalis

© Marge Talt

Corydalis seedpods are produced in quantity, but hard to see on the plant as they are tiny and blend into the foliage. Each pod has several seeds that have a caruncle that attracts ants who carry the seed to new locations. From what I've read, it seems the seeds also explode out of the pod, making purposeful collection tricky and making sure plants pop up some distance from the mother.

Fresh seed germinates quickly and in quantity. Seed of most species is short-lived; drying can send it into deep dormancy that may require more than one cycle of warm, cold, warm to wake them. Seedlings for many species will appear in autumn of the same year or the following spring when fresh seed is sown outdoors, either by you or the plant.

Many species require a cold period to initiate germination. The following germination requirements are from the Ontario Rock Garden Society Seed Germination Guide - a marvelous resource. Check it for species not described in this article.

• Corydalis lutea - Sow immediately. The viability of these seeds is short; seed is destroyed by dry storage for six months. Sow at 39ºF (4ºC) for two weeks, then move to 50ºF (10ºC) for germination.

• Corydalis ochroleuca - Sow immediately. The viability of these seeds is short; best with fresh seed. Sow at 68ºF (20ºC) for six weeks, then place 39ºF ( 4ºC) for six weeks, then slowly raise temperature to 50ºF (10ºC) for six weeks. If there is no germination, repeat the cycle.

• Corydalis solida - Sow immediately. The viability of these seeds is short; best with fresh seed. Sow at 68ºF (20ºC) for six weeks, then place 39ºF ( 4ºC) for six weeks, then slowly raise temperature to 50ºF (10ºC) for six weeks. If there is no germination, repeat the cycle. Leave seedlings in the same pot as seed was sown for the first year.

• Corydalis sempervirens - Sow immediately. The viability of these seeds is short; best with fresh seed. Sow at 68ºF (20ºC). Seed germinates within three months. Requires light for germination.

• Other species. If you can't find definitive germination instructions, you can either sow seeds in late summer or autumn and leave the pots outside all winter to expose them to fluctuating temperatures. I cover flats of pots with window screening to keep animals and debris out of the pots. It's even better if you can plunge the pots in soil or sand.