Q.Irises after stopped blooming
I live in Central Oregon. I have several Irises in my garden. When they stopped blooming, how should I cut them, or not cut them. I do not store them in the winter. They always come back in the spring.
Do I fertilize them and when? And with what?
Certified GKH Gardening Expert
It is not necessary to cut them back. They are naturalized just about everywhere, and can survive unaided. This article will offer insight to get them looking their best: https://www.gardeningknowhow.com/ornamental/bulbs/iris/iris-plant-care.htm
Iris require only division every 3 years or so. Without this, the tubers become crowded and fewer blooms are produced. Yearly addition of 1-2 inches of compost is all that is required for nutrition. If your soil is poor, a long-acting, balanced "flower" fertilizer may help. The large tuber that produced a bloom this year will never bloom again. These are discarded when dividing plants. Iris are one of the few plants that can be divided in late summer although choose a period of moderate weather, preferably cloudy. For now, prune out the flower stalk and let the leaves build up new tubers. When dividing, cut the leaves back to 6 inches tall and make sure each division has a fan of at least 3 leaves. https://www.gardeningknowhow.com/ornamental/bulbs/iris/iris-plant-care.htm