Late summer is a buzzy time for pollinators!


The last lazy, hazy days of August may be a time of rest for many of us, but it’s a buzzy time of year for our natural pollinators. Read on and learn how to make our backyards, gardens, and green spaces a late summer haven for pollinators.

Monarch butterflies

Monarch on Swamp Milkweed

Our local Monarchs are busy preparing to head south to Mexico for the winter, feeding as they go. Milkweed is a common native perennial which is getting ready to release its seeds at this time of year in Ottawa. It’s also the snack of choice for Monarch caterpillars that rely on it to get the nourishment they need to turn into butterflies.

Their diet makes the caterpillars (and butterflies) toxic to many predators, which they warn off with their bright colours. Monarchs take about four weeks to change from tiny caterpillars to beautiful butterflies. They spend the summer trying to build up their population levels, which are sadly declining. And in late summer, the last generations of Ottawa Monarchs need to eat well to fuel their marathon flight to Mexico.

“If you have Milkweed on your property, consider yourself lucky,” says Amy MacPherson, an avid naturalist and planner with the City of Ottawa whose work includes watching over the City of Ottawa’s pollinator garden. “It’s the host plant for Monarch caterpillars, and its flowers attract a wide range of other pollinators.”

“Adult Monarchs and other butterflies are less picky in their feeding choices and will visit a variety of flowers for nectar. It’s important to ensure that our gardens and meadows provide a diversity of flowering plants that bloom at different times of the year.”

Bumblebees on Goldenrod

Did you know? Although the tall and sunny Goldenrod is often blamed for late-summer allergies, ragweed is the likely culprit this time of year. So, don’t disturb this tall beauty in your garden or yard. It’s an important source of nectar for bees, butterflies and beetles!

Yellowjacket wasp on flower

Bees and yellowjackets

It’s easy to confuse some bees and yellowjackets (wasps) but they are very different. Late summer/early fall is an especially important time for both kinds of insects. Bumblebees and domestic honeybees are working harder than ever collecting reserves for winter colonies. Solitary bees are tucking their offspring away for the winter in burrows underground, or inside plant stems or holes in wood.

While yellowjackets are arguably less popular than bees, the species is very busy at this time of year, defending their underground nests and looking for food for themselves and their colony’s young. They can make gardening, mowing the lawn and even having a picnic a painful experience. But they’re helping us by hunting garden pests and scavenging spoiled fruit. With proper attention, you can preserve your garden for bees and protect yourself from yellowjackets!


Picture of Woolly Bear caterpillar

The cute Woolly Bear caterpillar delights kids and parents with their fuzzy coats. They are hatching now and will soon be munching on dandelions and grasses to prepare for winter hibernation. You may see the adults again in October when they look for a protected place to call home for the cold months. Mourning Cloak butterflies are also very active insect this time of year. If you look closely, you can watch them building up their food reserves to prepare for hibernation.

Did you know? Mourning Cloaks are considered the longest living butterfly, with a 10-month average life span for an adult. (source: Canadian Wildlife Federation)

Tips to make your garden pollinator friendly in late summer

Butterfly and bee on New England Aster

  • Fall is a great time to plant native perennials! This time of year, many gardeners will split their plants or collect seeds. Keep an eye on local neighbourhood networks to see if anyone near you is selling or sharing their plants and be sure to take advantage of end-of-season sales at local nurseries. Some good varieties that bloom at this time of year are asters, goldenrods, and wild sunflowers.
  • Don’t tidy up too soon! Pollinators don’t care that our mid-summer plants and flowers have lost their luster. They are still an important food resource. So, put away the shears and enjoy watching the natural pollinators take advantage of the late summer harvest.
  • Once the leaves start falling, resist the urge to rake! Keep at least some leaves in place and use them to mulch your garden beds. Leaf litter is an important habitat for many overwintering pollinators and other small wildlife.
  • For wildlife-friendly gardening, less is more. Dead plant stems are shelter for native bees and leaving seed heads in place over the winter provides food for goldfinches, chickadees and other resident birds

So, let August roll by with its droopy petals and plants and remember that our late summer gardens, yards, and green spaces are an important source of food and shelter for our City’s native pollinators.

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