Fall gardens can be absolutely glorious, with an abundance of lush foliage, copious blooms, showy seedheads, and brightly colored fruits. Once a few frosts have zapped your plantings, though, the show is pretty much over for the year. You may simply retreat indoors, leaving your plants to fend for themselves and delaying any cleanup chores until spring. Or you may choose to do a complete cleanup, cutting off the tops of your perennials just above the ground, followed by a thorough mulching once the ground has started to freeze.
Most gardeners end up taking an approach somewhere in the middle, such as cutting down some of their perennials but applying no mulch or leaving all the top growth on their plants and mulching around them. For the most part, perennials are surprisingly tough, so they’ll probably survive the winter just fine regardless of what you do or don’t do.
The “Let’s Get It Over With” Approach
If you think you want to do at least some cleanup before winter, don’t be too quick to get started. It’s fine to snip off the seedheads of any plants you don’t want reseeding as soon as their flowers fade. Go ahead and pull out any annual companions that got nipped by the first frost, too. Other than that, though, give your perennials a chance to die back naturally. You’ll know it’s time when their leaves and stems turn brown and dry — usually in early to mid-November.
One advantage of late-fall cleanup is that you’ll save yourself a lot of time in spring, when there are always so many other things that need to be done. You’ll also eliminate some places where insect and animal pests and disease-causing organisms can survive through the winter, possibly reducing problems when spring returns. If certain perennials frequently produce seedlings in your garden, getting rid of their seedheads can save you a lot of weeding next year. Removing debris right away means that you won’t have to worry about leaves matting down and smothering perennial crowns or emerging bulbs in early spring. And if you’re of the mindset that dead stems and seedheads simply look messy, then a late-fall cleanup will give you a tidy “blank slate” to look at through the winter.
The “I’ll Do It Later” Strategy
Procrastinators, rejoice: There are just as many good reasons to put off garden cleanup until spring as there are for doing it in the fall. For one, you get to enjoy an abundance of striking seedheads and fascinating plant forms through the winter months. Below is a precleanup view of the same area, showing the surprising amount of color and textural interest gardens can offer well into winter if you hold off on cleanup chores.
The remaining stems and foliage have practical benefits, too: They provide natural protection for ground-level buds and roots, and they trap and hold other leaves that blow into the garden, essentially making their own mulch. While all this “leaf litter” can shelter some problem pests, it also provides winter homes for lady beetles, ground beetles, and many other beneficial insects. Also, delaying cleanup gives the dead stems and leaves time to decompose right in place, so you’ll have a whole lot less debris to deal with — a big bonus if you don’t have much room for composting or if you have lots of gardens to deal with.
Wild critters will also appreciate your putting off cleanup for a while. Perennials such as goldenrods (Solidago), purple coneflowers (Echinacea), and ornamental grasses provide an abundance of seed that attracts a wide variety of migrating and resident songbirds in fall and winter.
The “Now and Later” Compromise
Most gardeners fall somewhere in between the all-fall and all-spring cleanup strategies, so they get the benefits of both approaches. Instead of tackling one big cleanup session, spread your cutting-back chores all through fall and winter, starting with perennials that have lost their good looks after the first few frosts. If you’ve had problems with fungal diseases on your peonies, summer-blooming phlox, or other perennials, put them on your early-cleanup list as well. By spring all you’ll have left to cut down are those with really long-lasting structure, such as warm-season ornamental grasses and fall-flowering asters.
Waiting until spring seems to be a good approach with agastaches, salvias, and other hollow-stemmed plants, too, the theory being that fall-cut stems provide a conduit for water to enter their crown and possibly cause winter damage. Spreading out your cleanup chores over several sessions also eliminates the big buildup of garden debris that you need to deal with all at once — a big help if you have limited space for composting!
Nancy J. Ondra
Nancy J. Ondra is a freelance garden writer and editor who owned and operated a small rare-plant nursery for six years. She is the author or coauthor of a dozen gardening books, including Fallscaping; Foliage: Astonishing Color and Texture Beyond Flowers, which won the 2008 Book Award from the American Horticultural Society); The Perennial Gardener’s Design Primer (winner of a 2006 Silver Award from the Garden Writers Association); Grasses: Versatile Partners for Uncommon Garden Design; and her newest release, The Perennial Care Manual. She currently gardens on her own four acres in Bucks County, Pennsylvania; works as a horticulturist at Linden Hill Gardens in Ottsville, Pennsylvania; and contributes to two garden blogs: www.hayefieldhouse.com and www.gardeninggonewild.com.