Holding off on spring clean-up

If snow, sleet, and freezing rain would stop falling, we’d all like to get outside and start our spring garden clean-up, right? Well, hold off a little longer. An update from my beneficial insect guru Jessica Walliser advises that we need to let last fall’s leaves lie and stems stand until temperatures warm up.

    Last year I learned I needed to adjust my approach in two ways to avoid interrupting the life cycles of insects I want to foster in my garden. There are several reasons to put out the welcome mat for insects. Beneficial insects prey on leaf-eating insects and help keep them in balance. 

Ladybugs eat leaf-eating insects

Pollinators are another desirable group of insect visitors, needed to help plants reproduce and make fruits, whether they’re cucumbers, squash, melons, apples, blueberries, or a host of other crops we take for granted. Even more importantly, we need a wide variety of insects for other animals to feed on. They form the base of the food web; without insects, larger animals will go hungry.

    Last year I heard that chopping up my fall leaves in the leaf shredder could mean I was chopping up insect eggs too. It would be better to let the leaves lie undisturbed through the winter so the eggs have a chance to hatch. So in the fall I cut back on shredding leaves and let more lie on the beds whole. 

Insects eggs laid on fall leaves will hatch in spring

My past practice has been to move these to the compost pile as early as April. Jess advises not to rake up those leaves until the daytime temperature is consistently reaching 50. 

    Second, I learned from Jess’ piece on fall clean-up that it’s best to leave plant stalks standing because many insects hide inside them through the winter. This went against my grain. It looked messy to have perennial stalks poking out of the snow, but I refrained from cutting them down. 

Insects could be hiding in this dead foxglove stem

     At this point I can cut the stems and pile them gently on the compost pile or under the evergreens at the back of the garden, or I can wait a few more weeks for the insects to emerge from their form of hibernation, called diapause. For more of Jess’s tips, see her spring clean-up post at Savvy Gardening.

    Last fall I also restrained myself from cutting down seed heads. Here the idea was that I could offer food for birds if I’d let the seeds stay. Birds are already singing their spring calls, so we know they’re out foraging for food, and I hope the flower seeds I left for them are helping them through the lean days of early spring. 

I left seeds on this spirea for birds to eat

     I’ve seen a few bees visiting the first crocuses, heralding the start of this year’s insect activity. I’ll be interested to see whether the changes I made in my fall and spring clean-up will bring a noticeable increase in the yard’s insect population this spring.

A bumblebee has already found these crocuses