Late summer is not only the best time to plant Bearded Iris for a jump start on spring growth, but also the time to care for your existing Iris by trimming old foliage back and, if mature enough, dividing and re-planting (or giving away to friends and neighbors)! Here are a few tips on planting and care to get you busy in the garden!
Planting New Irises
There are two different planting cycles for Bearded Iris – spring and fall. Typically, Bearded Iris are planted as rhizomes in the fall and potted plants in the spring. We have over 15 varieties of Bearded Iris rhizomes available to plant now. The benefit of planting Bearded Iris in late summer is to establish their roots before winter, giving them a jump start on growth in the spring. This results in the plants most likely blooming in their first year. The extra growth on top of summer-planted rhizomes is from last season; it can either be kept on or clipped off, it does not affect the actual growth of the plant.
Caring for/Dividing Existing Plants
Late Summer is the best time to care for and divide your existing Irises; their life cycle is at a point where they can be tended to, up-rooted, divided and re-planted. You will notice old foliage starting to wilt from the heat (especially this year!) – This foliage should be trimmed back regardless if you are planning to divide or not. Trimming also helps when dividing iris because it helps keep the moisture of the plant in the root system, not the foliage.
Dividing your Iris is fairly simple. Carefully dig the mature Iris up, making sure not damage any of the root systems. Cut each rhizome vertically with a sterile knife and be sure that each faction has at least 2-3 fans. If possible, try dusting the freshly-divided rhizomes with organic fungicide to prevent root rot or bores. Dig a shallow hole and spread roots out; make sure to leave the rhizome partially exposed (do not bury it completely) and water well. Bearded Iris are not only the epitome of elegance and grace, but are the true backbone of the perennial garden and are extremely easy to grow and care for, especially in late summer.