Leave the seed heads be
Autumn colors have started to paint the landscape. As beautiful as those reds, oranges and yellows are, many gardeners tend to focus too much on the formerly green perennials that are now a crispy brown.
What may seem ugly to you, however, is a happy winter home for a beneficial insect or food for an overwintering bird. Therefore, try your best to only remove what is really necessary.
Wait for a few hard frosts to occur and then assess the plants in your yard. Perennials with foliage that is browned or blackened, like peonies, daylilies and speedwell should be removed. Hosta plants should be cut back and all foliage removed to avoid harboring slug eggs over the winter.
In the vegetable garden, clean up can be thorough. Pests that plagued your crops this year may overwinter in the plant debris so clean that out. Likewise, pull weeds now before they become established.
Diseased perennials are the last category of plants to remove. Bee balm and phlox are often victims of powdery mildew. Even if they were not afflicted this year, cutting them back will help avoid that next season.
Remember to put any diseased plant parts in the garbage or bury them but not in the compost, unless your compost pile is active and reaches temperatures above 131 degrees Fahrenheit for at least four hours. Be sure to clean your tools and gloves after handling them.
Beyond that, many perennials can — and should — be left standing in your landscape. Low-growing evergreen or semi-evergreen perennials like hardy geraniums, heucheras, moss phlox, dianthus and hellebores should not be cut back.
Marginally hardy perennials such as garden mums and anise hyssop also will be better protected if left standing during the winter. The plants will collect leaves and snow, providing them with insulation and moisture.
What else should you leave in place? Plants that will provide winter interest such as ornamental grasses. They will flutter in the late fall breeze and then offer three-dimensional beauty to your snow-covered landscape. The grasses can be cut down in the spring once new growth appears.
Keep any cut or broken stems in the flower bed to provide a winter habitat for beneficial insects. Hollow stems offer a place for native bees to nest and other insects to lay their eggs.
Flowering perennials such as black-eyed Susan, purple coneflower, Joe-pye weed and stonecrop contain seeds that can sustain overwintering birds. In addition, leaving these plants standing allows them to catch leaves, giving them extra insulation.
Speaking of leaves, don’t be in such a hurry to rake them up and put them in the compost pile. Leaves are an excellent insulator on your flower beds, or they can be mulched on the grass with a mower. They are also important habitat for woolly bear caterpillars and provide protection for the bumblebee queen who burrows into the soil under a cover of leaves.
As you gaze out at your “messy” fall landscape, know how much the birds, bees and beneficials appreciate you.
(Amy Simone is a University of Vermont Extension master gardener from South Burlington.)