Marissa Ahlering is science director for The Nature Conservancy in Minnesota and the Dakotas. She’s a trained prairie ecologist. But she also has a small patch of native plants in the backyard of her Moorhead home.
“It's nice to have the flowers in the summer. But if you really want to think about a pollinator garden, you have to think about it all year long,” she explained as she checked the sprawling collection of milkweed plants.
“Most of our pollinators and insects are nonmigratory, the one that gets all the attention is the monarch, which migrates. And so it actually doesn't spend the winter here. But most of them do. And so we have to think about where they live over the winter.”
The same plants you might see bees snacking on in the summer, provide winter protection for a variety of insects.
“Leave the plants standing, leave the dead vegetation,” said Ahlering. “I will pretty much leave all of this untouched for the fall, and through the winter, and then even somewhat into the spring,” of her top recommendation for fall pollinator garden care.
“And certainly our bees will be in some of the leaves, some of the leaf litter, in the soil. Other things can do that, like wasps. Some of the butterflies and moths don't really usually burrow into stems, but they will attach to leaves or to the base of grasses, like down in the dead vegetation, to spend the winter there,” she said.
MPR News is Reader Funded
Before you keep reading, take a moment to donate to MPR News. Your financial support ensures that factual and trusted news and context remain accessible to all.
“Some of them burrow into stems of flowers, and some of them burrow into leaf litter, and some of them burrow into the ground. And so you need to make sure you've got, you know, kind of that variety of habitat for them to overwinter.”
Leaving native plants standing over winter will also provide habitat for birds.
“The birds really like the dead standing stuff, and also the seeds,” said Ahlering. “Like if you've got coneflower, they love those seeds. And so as they're migrating through in the fall, but then also if you leave it, in the spring, it can be really great for the birds.”
Another fall recommendation, leave some leaves. Some insect species will live under that ground cover through the winter. But it’s also important to have some bare soil.
“Bare ground is important for a lot of our bees, they will burrow into the ground to overwinter. And so if you have a lot of really dense leaf litter, that can make it really difficult for them to get through and really kind of inhibit them from from nesting there, and some of them actually nest there during the summer too,” Ahlering explained. “Having some variation in leaf litter, or dead vegetation and bare ground in your pollinator garden will be good for supporting the different variety of insects.”
Those standing grasses and flowers also might catch snow over the winter, providing a good soaking for the garden when the spring thaw arrives.
And Ahlering isn’t in a hurry to clean up the garden in the spring. Even if the plants are flattened by snow, insects might still be living inside.
And if you do cut down dead vegetation in the spring, leave the stalks in the back of the garden until early summer to ensure the insects can safely emerge.
Ahlering suggests following a simple rule.
“Messy is good. You know, prairies are not manicured places. And that's where most of these species evolved and are used to living,” she said. “So if we're trying to create habitat for them, you know, kind of mimicking that messiness is good, having all of the different diversity of structures.”