Blue Cohosh a shade-loving plant valued for its bluish-green foliage that emerges smoky-purple in spring, as well as its clusters of blue, fruit-like seeds that appear in summer and last into fall. It is best grown in shady areas in rich, moist soils typical of a woodland floor where it is found naturally. It needs consistently moist soil that does not dry out. Plants grown from seed typically take three to four years to flower. It eventually forms colonies, making it a suitable option for naturalizing shade gardens or establishing vegetation in the understory of deciduous trees.