3rd week of September:
I notice you've cut down irises already. Is that okay?
- S.J. -
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It's perfectly okay. Irises, peonies, coneflowers, daylilies, we're cutting at will, now. Some for their health, most for our visual pleasure.
Some perennials, including peonies and iris, are better cut early than late. When we remove iris foliage from the bed after early September, we're also fending off next year's pests by removing iris borer eggs laid on those leaves. We cut peonies early to stay ahead of botrytis, a leaf disfiguring, flower bud killing disease. By October what were just purple-brown blotches on the leaves and stalks at Labor Day may have traveled down the stem and infected the crown, ready to start trouble in the new year.
Pest trouble aside, we don't cut gardens down all at once in late fall. It's too depressing to go from merry fullness to moonscape in one day. Instead, we cut a bit at a time throughout fall. We're not out to scalp anything, just take away all the tall stems and debris. Perennials that develop a basal rosette for winter keep that nice looking new foliage. Others produce some new growth after the cut, which is not a loss to the plant and can even refresh a late fall scene.
We've been doing this ruthless cutting for 30 years without ill effect, ever since it occurred to us that Ma Nature does the same thing in our region when killing frost comes earlier than usual, in September. That the plants survive this means they must be capable of early check out. And why not? By Septemebr they've had a 5 month growing season, and that's plenty.
Ma Nature's killing frosts can start cutting things down in September in our region. So we have no qualms about cutting early.
- Janet -
We do make exceptions. We ask ourselves before the cut: