The ideal time for division is every three to five years between late summer and early fall (July to September). This ...
They are reliably perennial, so dwarf irises will come back every year as long as you choose a variety that suits your plant hardiness zone. Allen Pyle, a horticulture expert and outreach specialist ...
I visited her just after she had bought some iris bulbs at her local nursery and learned how they multiply, with the mother plant in the middle producing a circle of youngsters around her.