Cutting perennial’s dead foliage to the ground in the fall certainly won’t hurt them. Once the stems are dead, they’re dead! Cutting plants back also means one less task in the spring and keeps things looking neat and tidy.
However, cutting back the dead stuff may hurt any beneficial bugs that have moved into their winter digs aka the hollow stems and dead foliage of your plants. Just as they’re happily settling in for a long winters nap, snip, snap, whoosh, go your pruners and there goes their winter home.
If this bothers you, but the sight of all the dead foliage or the thought of all that work awaiting come spring bothers you more, there are some compromises that can be made.
You can cut the foliage down, and then carefully transport it – bugs and all – to a sheltered corner of your yard and pile the debris where it won’t blow around in the winter winds. Once spring temperatures are consistently above 10 degrees Celsius you can safely assume the bugs have made their winter exit and the foliage can quickly be popped into the compost bin.
If you live in an area that gets lots of chinooks that result in wildly fluctuating temperatures and snow melting and returning over the winter like I do, leaving the foliage in place not only benefits the bugs, but helps shade and trap snow around the base of the plants. The snow acts like an insulating blanket which helps ensure the plants survival during extreme conditions.
Some gardeners find the sweet spot by electing to cut their perennials down by half. Shorter stems remain to trap the snow – and provide much needed habitat for bugs – while leaving things looking tidier with less work come spring. Any top parts you cut off can still be carefully stowed somewhere for the insects, as described earlier.
Personally I love the look of snow and frost on the dead foliage. A lot of gardeners refer to this as “winter interest”. It also makes me happy to think of all the bugs dwelling inside. However, I live on an urban lot and have one of a very few front yard gardens. While we don’t have a HOA, I still try to appease the neighbours by keeping the front as tidy as possible. A lot of my garden is on what is technically city property. If no one complains the city looks the other way. Since I covet every precious inch of space I can garden on, I don’t want anyone to complain. The backyard, on the other hand, is left tall and wild going into the winter. It is also where my stack of front yard “half clippings” reside.
Thanks for reading, wherever you are, and however you choose to prune!