Now that spring is on our doorstep, many of us are getting anxious to head out to the garden and clean things up. I know I am. We see all the dead ornamental grass stalks, the spent perennial stems, and the autumn leaves collected in our gardens and they give us spring fever. We want to bolt outside and spring clean the garden as soon as we can because we know that as the days get warmer, there will be more and more gardening chores to do. But, don’t head out with your favorite clippers and rake just yet! There’s a right way and a wrong way to do a spring garden clean up.
You may recall that last fall I wrote a post on all the reasons why you shouldn’t do a fall garden clean up. The post encouraged you to let your garden stand all winter in order to provide habitat for many of the beneficial insects and other creatures living in it. The post went viral (!!!). So now, spring has arrived, and if you didn’t do a fall garden clean up as I recommended in that post, you now have a big spring garden clean up facing you. Along the same vein as my fall post, I’d like to now offer you some spring garden clean up tips that encourage a similar level of habitat preservation for beneficial insects.
How to do a spring garden clean up the RIGHT way:
Step 1: Cut, bundle, and tie.
In early spring, many insects are still in diapause (a physiological state akin to hibernation). In other words, they’re still sleeping. Sometimes they wake up because the weather warms and sometimes they wake up because the day-length increases. Lots of beneficial insects, including pollinators like tiny native bees and pest-munching predators like syrphid flies, lacewings, and parasitic wasps, spend the winter hunkered down in hollow plant stems either as adults or pupae. Cutting down the dead plant stems too early in the spring will disturb them before they have a chance to emerge. Wait as long as you can to do your spring garden clean up. Ideally, you should wait until the daytime temperatures are consistently above 50 degrees F for at least 7 consecutive days. But, that being said, I’m well aware that gardeners like to cut down old plant stems before new growth starts, so as an alternative to delaying your spring garden clean up, here are two other options:
- Toss cut perennial and woody plant stems onto the compost pile very, very loosely, or spread them out at the edge of the woods. Many of the insects taking shelter inside the plant stems will still be able to emerge when the time is right. When you cut off the plants, leave about 8 inches of stubble behind. These hollow stems will serve as overwintering sites for future generations of insects and the new growth will soon hide them.
- Another option (and the one I prefer) is to take the cut stems and gather them into small bundles of a few dozen stems each. Tie the bundles together with a piece of jute twine and hang them on a fence or lean them against a tree on an angle. Again, the insects sheltering inside of them will emerge when they’re ready. An added bonus of this method: More insects, especially native bees, will move in to the stems and possibly use them as brood chambers all summer long.
Related post: Supporting native bees
Step 2: Do a CAREFUL leaf clean up
Again, waiting as long as possible to rake leaves out of perennial beds is the best idea. Hold off on your spring garden clean up until daytime temperatures consistently reach the 50s, if possible. Scores of beneficial insects – ladybugs, assassin bugs, and damsel bugs, for example – hunker down for the winter in leaf litter as adults. Others do so as eggs or pupae. And, adult butterflies, such as morning cloaks, question marks, and commas, nestle into leaf litter for the winter. Luna moths spend the winter in cocoons that look just like a crinkled brown leaf. As you clean up your leaves keep a sharp eye out for these insects and do your best not to disturb them.
Step 3: Don’t mulch… yet!
There are also many beneficial insects and pollinators who overwinter in soil burrows as either eggs, pupae, or adults. Some examples include the hummingbird clearwing moth, soldier beetles, and many native bees. Covering the ground with a layer of mulch too early in the spring may block their emergence. Hold off on mulching chores until the soil dries out a little and the weather warms.
Related post: 5 late-blooming pollinator friendly plants
Step 4: Prune with great care
If part of your spring garden clean up involves pruning back woody perennials or shrubs, keep a sharp eye out for cocoons and chrysalises. Some of our most beautiful moths and butterflies spend the winter in a delicate cocoon dangling from a branch, including the swallowtails (see feature photo), the sulfurs, and spring azures. Allow any branches with a cocoon or chrysalis present to stay intact. You can always cut them back later in the season.
A proper spring garden clean up should NOT be a destructive process. By taking your time and doing it right, you and your garden can reap the many benefits of a healthy population of pest-munching beneficial insects and pollinators.
Do you have any other tips for conducting an insect-friendly spring garden clean up? Share them with us in the comment section below.