Propagating Corydalis should be done in early spring/late winter because this is one perennial that will bloom from spring, March/April, until early fall, but only in cooler climates, Zone 5, otherwise in warmer zones it has a tendency to go dormant in mid summer and may or may not sprout again in the fall. In warmer zones I suggest that you plant in an area that does not get afternoon sun and that is susceptible to wind for a longer blooming period and since it does not appreciate summer drought make certain the soil is a heavy rich mixture and not sand nor gravel. Corydalis will reach a height of up to 12" and variety colors range from purple, chocolate, pink, yellow, white, red, blue, tends to be deer resistant, is evergreen and fragrant.