The Iris 'Alida', Iris reticulata , is a tiny iris that blooms in late winter and tolerates either sun or shade. Plant these pale blue irises at the base of the perennials that are slow to appear as "living flags" to help keep you from stepping on newly emerging shots in spring.
These are dwarf, bulbous irises, flowering in late winter and bringing most welcome early colour to the garden. The flowers are relatively large, barely twice their own height above the soil, but are followed by much taller, slender leaves. They reach a height of 6 inches.