How to Support Pollinators Through the Winter

Photo courtesy of Cynthia Brast
Leafcutter Bee Megachile.

Photo courtesy of Cynthia Brast Leafcutter Bee Megachile.

After blustery storms displace sprinkles of red, orange, and yellow autumn leaves, one may be tempted to rake the mess out of their yard, but local entomologist Cyntha Brast urges you to think twice before you do! Over-raking or over-pruning in the winter can wreak havoc on the important pollinators seeking shelter that will come out in the spring.

“We have overwintering pollinators and also very important overwintering pest predators,” Brast said. “Both need to have vegetative cover in order to survive the winter and emerge in spring.”

Due to there being no winter time pollinators, it can be easy to adopt an out of sight, out of mind way of thinking about the important insects, but the impacts of that will be apparent once spring comes around. Unbeknownst to many, when disturbing the insects in the leaves and branches, this is already setting the stage for spring and whether or not it will be a successful one for flowers, crops, and other vegetation.

According to Brast, some of the overwintering pollinators consist of flies, native solitary bees, bumble bees, wasps, moths, ladybugs, lacewings, and butterflies. These insects may be developing in perennial plant stems, pupating under fallen leaves, twigs, and branches, beneath edges of bark on trees, as cocoons attached to shrubby plants, rolled along edges of leaves, in woody debris on the forest floor, and even under rocks, or in the ground. Some have pupal cases or eggs that are attached to shrubs and tree branches. Many also lay eggs on associated host plants, so that hungry hatchlings have a buffet waiting when they emerge in spring.

“Each species seems to find or have its own special niche,” said Brast.

In fact, the island’s native shrub Ocean Spray, is a very valuable host plant.

“If you prune this native shrub and cart off all the clippings, you are eliminating the lives of over 16 different species of Lepidoptera that utilize this shrub for development, including some really beautiful butterflies like the Elegant Sheepmoth,” said Brast.

It may seem unreasonable to leave a mess of leaves or branches in your yard, but Brast has a way of working around that.

Pruning and clipping is fine, she said, as long as those clippings are left nearby rather than burning or chipping them. In fact, it’s a good idea to make mounds of clipping and prunings for the pollinators to take shelter in, said Brast. If you can, leave your perennial stems and garden clean up until temperatures have reliably warmed to a daytime high of around 50 degrees.

As for leaves, she said it is beneficial to the pollinators to wait until spring to tidy up, encouraging people to not be afraid of a little bit of mother nature’s mess.

These clippings and leaves can also be utilized by creating shelters for other animals, like birds and reptiles, she said.

Keep in mind that many of our pollinators aren’t going to be out flying until late April to mid May, and timing of emergence will typically occur with the blooming of available food sources.

Thinking about starting a garden? “Pollinators are critical in our environments to help with food production and the perpetuation and preservation of the life cycle of many trees, flowers, plants, and shrubs that not only feed humans, livestock, and our pets, but also feed the lives of the multitude of other living organisms we share the planet with,” Brast said. “They are an essential part of our food web!”