This evergreen ferny little plant blooms on and off most of the year. It has happily reseeded so I have spread them throughout the shady garden. Yes, corydalis prefers shade. I also have corydalis 'Blackberry Wine', that dies back in the heat, but spreads a good six feet, producing its purple blooms for several months in spring. Most corydalis have blue or yellow blossoms. I prefer this white with green and yellow markings, but corydalis is a species I plan to pursue.