Corydalis (pronounced kor-ID-ah-liss) starts blooming in May with the late spring-blooming Tulips and is still blooming with fall’s Asters. The best part is that this plant never requires deadheading to keep the flowering show going strong, so it is considered the longest of the long-blooming Perennials.
Corydalis lutea or Yellow Corydalis blooms are so interesting with their flared, spur-like tubes of brilliant yellow that it doesn’t matter that they are only an inch or so long. They do a grand job at lighting up a shady garden spot despite their size.
Corydalis only appears to be delicate. In fact, it is a tough, undemanding, maintenance free, partial shade plant that looks delightful in the garden. It grows in a fifteen-inch ball shape and holds this lacy, refined shape all season. Its small size, pristine compactness, and long bloom time gives this charming little plant status for being planted as an edger along the front of the border. For the same reasons, Corydalis is an attractive plant for a container or planter. Its preference for good drainage and alkaline soil also gives it priority as a rock garden plant as long as the area is somewhat shady, for it prefers cool conditions.
Corydalis resembles a smaller version of Dicentra or Bleeding Hearts because they are related. Both perennials have the lacy, blue-green, deeply divided foliage and uncommon flowers, but Corydalis will not go dormant when summer temperatures heat up. One other factor is that Bleeding Hearts are a hardy zone-three perennial while Corydalis is listed as a zone-5, but it grows beautifully and winters well in my Brigham City gardens. The constant blooming of Corydalis provides a wealth of seedling germination while Dicentra rarely reseeds. The seedlings can be transplanted or weeded out by simply turning the soil in spring but the Corydalis plant is short-lived in comparison to Bleeding Hearts. For this reason, I recommend letting some seedlings reach maturity. Pictures of both perennials show their very unique flowers.