Iris tectorum Alba
Iris tectorum ‘Alba’ is a prized selection of the Chinese roof iris. No, it’s not from Japan despite rumors to that effect and a poorly chosen common name. The slowly-spreading semi-deciduous patch is composed of wide light green foliage. Starting often in mid-March and continuing well into May in NC, the easy-to-grow clumps are topped with frilly white flowers held above the foliage. Iris tectorum ‘Alba’ thrives both in dry shade and on damp roofs…anywhere as long as the drainage is good.