Category Archives: Bees & Pollinators

Advice, Bees & Pollinators, Garden Design, Native Plants

Diversity: One Earth, Many Ways to Grow

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By Amanda McIlmoyle, Master Gardener in Training

“Nature does nothing uselessly.”  Aristotle

Diversity is one of nature’s greatest strengths. Every organism, from the smallest insect to the largest tree, plays a unique role in the overall health of a garden. Nature is purposeful, deeply connected, and rewards us with incredible beauty when we provide our plants with the environment they need to thrive.

There are countless ways to think about diversity in the garden. From the types of plants we select, the wildlife that populates them, to the gardening practices that encourage a healthy microbiome in our soil, the topic of diversity is vast.  As gardeners, we spend a great deal of time planning our spaces to make them uniquely our own. However, when people think about diversity, their focus often shifts to visual diversity. While aesthetics are absolutely important, as our spaces are, after all, a reflection of our personality and preferences, the visual piece is just one part of a much larger puzzle. Let’s look beyond the visual appeal for a moment and explore a handful of other ways diversity truly matters.

Why Diversity Matters:

  • A diverse garden supports a healthy soil microbiome.  Diversity helps manage harmful pathogens, it improves nutrient cycling and feeds the beneficial organisms in the soil. 
  • Diversity also improves the soil structure.  A variety of plant root systems can help create channels within the soil that improve the flow of water and oxygen while providing different habitats and food sources for soil organisms.
  • Diversity in the garden also supports native pollinators, such as bees, butterflies and even beetles, wasps and hummingbirds along with all sorts of other beneficial wildlife.  A variety of plants provides these vital creatures, with a continuous supply of nutrients and areas for shelter.

How Do We Work Towards Diversity:  

  • Incorporate native plants into your garden, as these provide food and shelter for local wildlife while also supporting pollinators and wildlife.  Its important to become familiar with the native plants in your specific area as these plants thrive in local growing conditions along with local ecosystem. 
  • Choose a variety of plants with different shapes, sizes and bloom times to provide broader options of food sources and shelter for pollinators and wildlife throughout each growing season.   
  • Avoid harmful chemicals, as much as possible as they can alter the health of the soil and negatively impact the beneficial bugs in the garden. 
  • Leave spent foliage in the fall as dead stalks, mounds of leaves or dead flower heads can provide food and shelter to wildlife and pollinators during the colder months. 

Nature provides us with what we need to not only survive but to also thrive.  In a natural environment, there is a continuous exchange amongst producers (organisms that create their own food), consumers (all living things that rely on producers for food) and the decomposers (organisms that turn waste back into essential nutrients that feed producers). 

As gardeners, we act as environmental stewards; whether consciously or unconsciously, through the basic act of gardening.   For me, it doesn’t matter if your garden consists of a handful of houseplants , containers on a balcony,  an assortment of perennials or natives or expansive fields as part of the larger farming community.  Simply by gardening, we have an opportunity to contribute to the health and diversity of our planet. 

In short, diversity matters!

Resources

Bird-Friendly Gardens: Supporting Bird Habitat in Every Season

5 Reasons to Grow a Diverse Garden

Why is Plant Diversity Important for a Garden?

Pollinator Garden: A Toronto Master Gardeners Guide

Advice, Bees & Pollinators, Botanical Names, Butterflies and Moths, Invasive, Native Plants, New Gardens, Planting, Shade Gardening, Sun Gardening, Wildflowers, Winter Sowing

Beware those Wildflower Mixes!

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    By Emma Murphy, Master Gardener

    The Oxford Dictionary defines “wildflower” as “a flower of an uncultivated variety or a flower growing freely without human intervention.”  It has nothing to do with the species’ native range, its benefits for pollinators, or its impacts on ecosystems. A “wildflower” could be native, non-native or at worst invasive.

    Last year at this time, I wrote a blog post about roadside wildflowers. Most of these flowers (like chicory [Cichorium intybus] on the left or Oxeye Daisy [Leucanthemum vulgare]) are non-native opportunists from Europe or Asia that colonize quickly on disturbed sites or ditches and wetlands and outcompete native species, but lots of people assume they are native because they’re everywhere along roadsides (I did for years!).

    The bottom line? Wildflower does not equal native.

    So, if you want to buy a wildflower mix to create a long-term habitat for native pollinators, beneficial insects, and bees in your gardens, the mixes found at big box stores and large nurseries are probably not the mixes you want.

    Why the Label can Mislead

    A lot of retail “wildflower” mixes are designed for fast colour. They focus on non-native annual flowers, which bloom quickly and beautifully in the first season but fail to support local pollinators (and isn’t that the point?), or can even become invasive.

    While mixes don’t need to be exclusively comprised of species native to Ontario to provide good habitat for pollinators and beneficial insects (although that’s the best case scenario), they shouldn’t be invasive and should be perennials so that your garden continues to look good year after year.

    Why is this Important?

    Pollinators need more than flowers that simply look pretty. They need plants that fit local conditions and provide food, shelter, and nesting support over time – that are beneficial to the local ecosystem.

    What’s the biggest red flag? Seed mixes that only provide the common names of species instead of the scientific (Latin) names. While common names can be easier to remember and pronounce, they also vary by region, and one plant can have several different common names. This can cause confusion about what the actual species is.

    A Case in Point

    Last year at the PMG A Day for Gardeners a lady approached me with a large bag of pollinator seed mix as I was working on the advice table. She wanted to know if it was good. There were no Latin names (first red flag) so I asked her to leave it with me to investigate.

    After checking as best I could we determined that almost 80 percent of the seeds were not native and were annuals. She planned on returning the bag to the store.

    The Problem with Mixed Seed Packets

    • Big companies that sell across Canada create one seed mix to sell across the entire country but what might be native in Alberta probably won’t be in Ontario
    • Seeds have different germination requirements so you may find some seeds don’t germinate at all
    • Different seeds may not grow well together
    • Some seeds may not like your site conditions and others may become dominant

    The worst problem is if they contain non-native, invasive seeds.

    Let’s look at an example. McKenzie Wildflowers Pollinator Mix.

    1. Only five flowers native to Ontario (*) and all less than 5% of the mix except for the Purple Coneflower, which is 12.67% and Lanceleaf coreopsis, which is 6.33%
    2. The first three flowers, which comprise over 42% of the mix, are all non-native
    3. Your seeds are only 14% of the mix – the rest is vermiculite (filler)

    Here’s a full breakdown.

    Better Ways to Choose

    The best seed mixes are transparent. They tell you exactly which species are included, how much of each is in the packet, and whether the plants are native to your region. Regional native mixes can be useful, especially when they include a balance of annuals and perennials and are clearly suited to your regional climate.

    If you’re serious about supporting biodiversity, the most important thing you can do is choose seeds that are native to your specific region.

    I’ve seen several companies create better wildflower mixes in the past few years, including Northern Wildflowers, Native Plants in Claremont, OSC and, for large projects, St Williams Ecology Centre. I’m sure there are others I have missed so be sure to comment if you know any!

    One key thing to remember with native plant seeds is that most need winter stratification (a cool, wet natural dormancy period over winter) to germinate well. That means that direct garden sowing should take place in the late fall after the first frost (mid-September to November, depending on your region), not in the spring. If seeds can’t be stratified, many will not germinate until the following spring and germination rates may be slightly lower.

    A Simple Rule for Gardeners

    If your goal is to truly help pollinators, choose local native plants first and sow your seeds in the fall for best germination. Avoid mystery mixes (especially those with only common names), check the label closely, and be cautious of bags that promise an instant meadow without giving details. Colourful flowers are nice, but real pollinator support comes from the right plants in the right place, and that doesn’t happen overnight.

    Choose the Right Seeds – Go Native, Not Just “Wild”


    Additional Reading

    Bees & Pollinators, Hedging, Shrubs & Trees, Wildflowers

    Huzzah for the Hedgerow! The Hardworking Helper Our Countryside Needs

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    By Thomas Luloff, Master Gardener

    This past fall, I had the opportunity to spend several weeks in southwest England while completing a teaching secondment at Hartpury University. As a conservation biologist from Ontario, I expected to learn about agriculture, veterinary science, and education. What I didn’t expect was to become completely fascinated by hedgerows.

    Everywhere I looked, the English countryside seemed stitched together by them. Ancient lines of hawthorn, blackthorn, hazel, dog rose, and mature trees divided fields into a patchwork quilt of green. Even in heavily farmed landscapes, there was always a hedge nearby. For wildlife, these weren’t simply field boundaries; they were highways, restaurants, nurseries, and safe havens all rolled into one.

    In the United Kingdom, approximately 70% of the land is farmed, leaving relatively little truly wild space for nature. Yet despite this, England still contains roughly 400,000 kilometres of managed hedgerows; enough to circle the Earth almost ten times. These hedgerows are considered the most widespread semi-natural habitat in the British countryside and support hundreds of species of plants, birds, mammals, reptiles, insects, and fungi.

    Walking through the countryside, it became obvious why they are so important. Hedgerows are alive. Their spring blossoms feed pollinators. Their berries sustain birds through winter. Their tangled branches provide nesting sites for songbirds. Badgers use them as travel corridors. Bats follow them like aerial highways. And of course, perhaps their most famous resident, the hedgehog, relies heavily on hedgerows for shelter, nesting sites, and protection from predators. Hedgerows are often described as “wildlife corridors,” but that phrase barely captures their value. They are entire ecosystems stretched across the landscape.

    What struck me most was how different this is from much of rural Ontario.

    Across Canada, agricultural fields have grown steadily larger as machinery has become larger and more efficient. Fence rows have disappeared. Small woodlots have been removed. Wetlands have been drained. In many areas, hedgerows have been sacrificed in the pursuit of uninterrupted fields that can accommodate modern equipment.

    For us, crossing a large corn or soybean field might seem insignificant. We can simply walk across it in a few minutes. But imagine being a sparrow, salamander, garter snake, or tree frog. Suddenly, that open field becomes a vast and dangerous desert. There is no shade. No shelter. No water. No protection from predators overhead.

    Many songbirds move through landscapes one patch of cover at a time, flitting from branch to branch and shrub to shrub. A large exposed field can become an effective barrier, isolating populations and making it difficult for wildlife to access food, nesting sites, and mates. Research consistently shows that hedgerows improve habitat connectivity and allow wildlife to move safely through agricultural landscapes.

    The benefits extend beyond wildlife.

    Hedgerows are remarkably effective environmental infrastructure. They reduce wind speeds, helping protect crops and soils. They capture snow during winter, slowing runoff and helping recharge groundwater. They reduce soil erosion, intercept nutrients before they reach waterways, and store significant amounts of carbon in both their woody biomass and surrounding soils. Research has shown that hedgerows can substantially increase soil carbon storage while also supporting biodiversity.

    These benefits feel especially relevant in Central Ontario, where severe windstorms and extreme weather events seem increasingly common. While we often think about climate resilience in terms of expensive infrastructure projects, sometimes the solution is as simple as planting trees and shrubs in the right places.

    The good news is that gardeners and landowners can bring some of the magic of the English hedgerow home. A hedgerow doesn’t need to be kilometres long to make a difference. Even a property boundary planted with native shrubs such as serviceberry, nannyberry, chokecherry, dogwood, elderberry (among so many others!), can provide food and shelter for wildlife throughout the year. Leave the berries standing through winter. Allow the vegetation to grow dense and somewhat untidy. Let it become a place where wildlife can hide.

    In a world increasingly dominated by large-scale landscapes and manicured spaces, hedgerows remind us that nature thrives in the margins. They are proof that conservation doesn’t always require vast wilderness areas. Sometimes it simply requires a line of shrubs connecting one patch of habitat to another.

    So here’s a hearty huzzah for the hedgerow; the hardworking helper of the countryside. Quietly holding soil in place, sheltering wildlife, storing carbon, slowing winds, feeding birds, and connecting landscapes, one branch at a time.  

    References

    Blair, J., Olave, R., & McAdam, J. (2018). Hedgerows as a Form of Agroforestry to Sequester and Store Carbon in Agricultural Landscapes: A Review. 4th European Agroforestry Conference.

    Hedgelink. (2024). Importance of Hedgerows. Retrieved from https://hedgelink.org.uk/guidance/importance-of-hedgerows/

    UK Centre for Ecology & Hydrology. (2024). Urgent Need to Enable More Farmers and Contractors to Revive England’s Network of Hedgerows. Retrieved from https://www.ceh.ac.uk/press/urgent-need-enable-more-farmers-and-contractors-revive-englands-network-hedgerows

    Woodland Trust. (2025). Hedgerows. Retrieved from https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/habitats/hedgerows/

    Royal Geographical Society. (2024). Mapping England’s Hedgerow Landscape. Retrieved from https://www.rgs.org/about-us/what-is-geography/geovisualisation/mapping-englands-hedgerow-landscape

    Advice, Bees & Pollinators, Birds, Garden Cleanup, Spring

    Spring Awakening, Silent Loss: What Ontario’s Bill 5 Means for Your Garden

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    By Thom Luloff, Master Gardener

    As the snow melts and the first shoots of green push through the soil, spring invites us back into our gardens with optimism. It’s a season of planning and of imagining birds returning, pollinators buzzing, and life rebuilding after winter. But while we prepare our gardens for renewal, something far less hopeful is unfolding across Ontario: the quiet weakening of protections for the very wildlife we love. 

    At the center of this shift is Bill 5, a sweeping piece of legislation that is fundamentally changing how species at risk are protected in our province. Under Bill 5, the Endangered Species Act, once considered a global gold standard for conservation, is being removed. Bill 5 narrows the definition of “habitat,” focusing only on spaces where species physically are, rather than the full landscape the species needs to survive. It also removes certain prohibitions, such as protections against “harassing” species, making it easier for disturbance to occur. 

    For wildlife, especially birds, this matters enormously. Habitat loss is the primary driver of species decline. When protections weaken, landscapes become more fragmented, nesting sites disappear, and food webs begin to unravel. The spring chorus we look forward to each year depends on intact ecosystems, and those ecosystems are increasingly under pressure.

    So where do gardeners fit into this? Right at the center of the solution.

    If policy is stepping back provincially, stewardship must step forward. Your garden is no longer just a personal space, it is a piece of habitat in a much larger, increasingly fragmented system. And the choices you make this spring can directly support species that are losing ground elsewhere.

    One of the most powerful actions is deceptively simple: leave some areas (especially the hard to get to ones!) wild. Resist the urge to clean everything up. Leaf litter, fallen branches, and standing stems provide critical overwintering habitat for insects. These insects are the foundation of the food web, feeding birds during breeding season when they need protein the most. Tidying too early can erase an entire generation of life before it has a chance to emerge.

    Planting native species is another essential step. Native plants support significantly more insects than non-native ornamentals, which in turn support birds, amphibians, and other wildlife. Even a small patch of native plants can function as a high-value habitat.

    Reducing harm is equally important. Avoid pesticides, which ripple through ecosystems. Make windows bird-safe to reduce collisions. Provide water sources and dense shrubs for shelter. These actions may seem small, but collectively they create real, measurable impact.

    Bill 5 is a reminder that conservation cannot rely on legislation alone. As gardeners, we are not powerless observers. We are active participants in shaping the landscapes around us.

    This spring, as you plan your garden, think about habitat. Think refuge. Think resilience.

    Because in a time when protections are being pulled back, the spaces we cultivate may matter more than ever.


    Reference


    The Narwhal. (2025). Ontario’s endangered species law is barely being enforced — and wildlife is paying the price. Retrieved from https://thenarwhal.ca/ontario-species-conservation-act-enforced/ 

    [Link to Bill 5]

    Bees & Pollinators, Birds, Bugs, Butterflies and Moths, Information, Insects, Native Plants, Tools, Websites

    iNaturalist — a tool to help you garden more ecologically

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    By Silvia Strobl, Master Gardener

    Are you curious about the birds, insects, and other wildlife visiting your garden? iNaturalist (free iOS/Android app) lets you photograph organisms, get AI suggestions on identification, and submit observations that expert naturalists can verify and researchers can use. Knowing which organisms are using your garden both gives you a greater appreciation of its contribution to the local ecology and can help you support visiting wildlife’s needs. A few examples of how you can use iNaturalist follow.

    • You can easily generate a summary of observations in your garden in iNaturalist–in my case 68 species of butterflies and moths in my garden north of Peterborough since 2021.
    This is just a partial summary of the species of butterflies and moths observed in my garden. Custom summaries can easily be generated in iNaturalist–no need to keep your own list!
    • Two summers ago I found caterpillars eating my Snowberry (Symphoricarpos albus). iNaturalist identified them as Snowberry Clearwing Moth (Hemaris diffinis). After pupating, they overwinter in leaf litter — so leaving leaves under trees and shrubs can protect its pupae and that of many other butterflies and moths.
    (Left) Caterpillar of the Snowberry Clearwing Moth feeding on Snowberry shrub but I have only ever seen the adult of the closely related Hummingbird Clearwing Moth (Hemaris thysbe) adult (Right), here nectaring on Salvia in my garden.
    • You can use iNaturalist to learn which species use your garden and then plant their host plants (required to feed its caterpillars). In 2024 I recorded a rare Spicebush Swallowtail (Papilio troilus) visiting Bee Balm (Monarda didyma). Its hosts are Sassafras and Spicebush — plants of the Carolinian Forest ecoregion. Researchers using citizen science records over an 18-year period have already documented North American butterfly range changes towards cooler and wetter locations with climate warming (da Silva and Diamond 2024). The next spring, I planted 12 seedlings of Spicebush. Although planting native species from further south of your location is generally not recommended, small experiments can be informative.

    I submitted the above 2 photos to iNaturalist. My observation was reviewed by one of Ontario’s foremost butterfly experts, Rick Cavasin, who verified it was actually a Spicebush Swallowtail. It is one of only a few observations to date of this butterfly in central Ontario.

    • You could also use iNaturalist to identify a species you want to attract to your garden. I recently heard about a Brooklyn Bridge Park (New York City) gardener’s success in attracting the pollen specialist Spring Beauty Mining Bee (Andrena erigeniae) by planting hundreds of its host plant, Spring Beauty (Claytonia virginica), over several years. Twenty-five percent of eastern North America’s 770 native bumble bee species are pollen specialists that can only raise their larvae on pollen from either a group of closely-related plant families, a single genus, or, even just a single species (Fowler & Droege 2020).
    Eastern Spring Beauty (above) and Carolina Spring Beauty (Claytonia caroliniana) bloom in early spring in northeastern North American woodlands. The pollen specialist, Spring Beauty Mining Bee can only raise its larvae on their pollen.
    • I am winter sowing Wild Geranium (Geranium maculatum) to support spring pollinators and to try attracting the Cranesbill Miner (Andrena distans) another pollen specialist, but this may be challenging because there are no reports of this species north of Peterborough (see map below). The lack of records could be due to fewer iNaturalist observers in this location and gardeners’ casual contributions could provide a more complete picture of biodiversity from their gardens.
    Observations of Cranesbill Miner (Andrena distans) on iNaturalist as of February 18, 2026.

    Getting Started with iNaturalist

    I hope you are inspired to use this tool. You can download either the iOS (for an iPhone) or android version of iNaturalist from the App Store. This quick video shows you how to use iNaturalist while this one provides more details and shows how you can use data in iNaturalist to learn which species have been observed in your local area.

    To Learn more about Ecological Gardening watch this TED Talk by Rebecca McMackin which has more than 450,000 views. 

    If you like butterflies, you may find this pocket guide to Ontario’s butterflies and moths by Rick Cavasin helpful. 

    Research Cited

    da Silva, C. R. B., & Diamond, S. E. (2024). Local climate change velocities and evolutionary history explain multidirectional range shifts in a North American butterfly assemblage. Journal of Animal Ecology, 00, 1–12. https://doi.org/10.1111/1365-2656.14132

    Fowler, J. and S. Droegge. 2020. Pollen Specialist Bees of the Eastern United States. https://jarrodfowler.com/specialist_bees.html

    Related

    Hosting butterflies

    The Kiss Principle–Winter Sowing 101

    Advice, Bees & Pollinators, Birds, Books, Communication, Dreams, Fruits, Greenhouses, Health, Herbs, Houseplants, Information, Native Plants, Overwintering, Perennials, Propagation, Vegetable Gardening, Wildflowers

    Time for Reading Garden Books

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    by Christine Freeburn, Master Gardener

    In this day and age, we spend so much time on our computers, googling all the information we want and need. But there is something about sitting by a sunny window on a cold winter’s day with a good book.

    The winter months are a great time to pull out an old gardening book or invest in a new one. The days are now getting longer and spring is coming, but actual gardening is a few months away. Time to learn something new to help you improve your gardening skills. There are many good Canadian and zone appropriate books that can help you.

    Below, I have listed a few of my favourite books on my bookshelf. I have also asked my fellow Master Gardeners to share their favourites. Some of the books are out of print, but check your local library, used book stores or online sites. Enjoy!

    For the Houseplant Gardener

    The New Plant Parent

    Darryl Cheng gives advice that is full of common sense. He explains that leaves do die and plant care should be enjoyable, not a chore. He discusses basic requirements for healthy plants including the right light, soil care and proper watering. Great illustrations and nineteen plant varieties are listed in detail. Look for his newer books also.

    For the Vegetable Gardener

    Plant Partners

    Companion planting has been around for years. Jessica Walliser gives us “science-based companion planting strategies” that help with disease and pests, improves soil and supports pollinators. Lovely illustrations throughout will have you dreaming of your next vegetable garden.

    Growing Under Cover

    Niki Jabbour is the Canadian half of the popular website Savvy Gardening (along with Jessica Walliser). She has several books out, but this one gives great information about how to reduce pests with row covers. Niki has several books out, so check them out.

    The Kitchen Garden

    Peterborough MG Silvia Strobl first toured Patrick Lima and John Scanlan’s garden on the Bruce Peninsula over 40 years ago and was inspired by both their colourful perennial and productive vegetable gardens. Each spring, she still refers to this book’s excellent information to refresh her memory on time to sow, spacing, thinning, harvesting, etc. for the vegetable crops she grows! Unfortunately, this book is out of print, but you may find a used copy online.

    Incredible Edibles

    This book by Sonia Day is recommended by Peterborough MG Deb Fraser. It is very basic for the beginner gardener. It answers when, where, how, as well as other questions for herbs and vegetables. She even gives a recipe for each plant. Another book that is out of print. Try used book sites.

    Encyclopedia of Herbs, Spices & Flavorings

    Deb also suggests the Encyclopedia of Herbs, Spices & Flavorings, a cook’s compendium by Elisabeth Lambert Ortiz. Originally British but published in Canada by Readers Digest, 1992. It is beautifully illustrated and very detailed about the origin of herbs, spices, oils, sauces, coffees and teas around the world. She details the origin of these, how to cook with them and a recipe. When the weather is frightful with a nice warm drink in hand it makes for interesting reading, perhaps planning to add a few herbs to your garden next spring.

    For the Perennial Gardener

    The Well-Tended Perennial Garden

    Peterborough MG Gladys Fowler’s favourite book is the Well Tended Perennial Garden. Tracy DiSabato-Aust’s book has an extensive encyclopedia of perennial species and cultivars and she explains the maintenance and pruning needs of each plant. The explanations and illustrations are excellent.

    For the Native Plant Enthusiast

    The Gardener’s Guide to Native Plants of the Southern Great Lakes Region

    For Peterborough MG Emma Murphy, definitely this one on native plant gardening – for our region, gives everything you need to know about growing the plant, including propagation, wildlife value and what butterflies and moths it is a larva host for. For a full book review she did on Rick Gray and Shaun Booth’s book when it was published in 2024 click here.

    A Garden for the Rusty-Patched Bumblebee

    Peterborough MG Sharleen Pratt says this book by Lorraine Johnson and Sheila Colla not only goes into great detail about Ontario native plants, vines, shrubs and trees, but it also encourages us all to think about the spaces we create so that pollinators can thrive.

    For the Environmentalist

    Our Green Heart

    Peterborough MG Carol Ireland says it feels good to sit down and read something that requires absolute attention while at the same time causes you to make all the connections between what you are reading and the place trees have in the survival of our planet. This one by Diana Beresford-Kroeger is also on my reading list!

    What is your favourite gardening book? What do you have on your list to find and read next? Eleven more weeks till spring!

    Check out previous reviews on our website

    Favourites From My Bookshelf

    Four Great Books

    Bees & Pollinators, Native Plants, Perennials, Shade Gardening, Sun Gardening

    What’s Still Feeding Pollinators in Your Fall Garden?

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    by Silvia Strobl, Master Gardener

    It has been a warm start to the fall season, but despite a little more frequent rain in September, the summer drought has continued here north of Peterborough in my 4b Plant Hardiness Zone garden. My soil is also sandy and dry. So what could still be blooming and feeding our most effective pollinators, the native bumble bees?

    Although bumble bees are more active in spring and summer, they still need nectar and pollen in fall because the gynes, unmated females that will become next year’s new queen bees if fertilized, are mating and then must build up fat reserves and find a place to overwinter (The Xerces Society 2025). At this time of year you may see bumble bees sleeping on flowers in the morning, especially after a cold night or overnight rainfall. These are mostly the solitary male bumble bees that sleep outdoors. They are searching for a mate, and then they will die. Bad weather may also force female bumble bees to sleep outdoors, but their preference is to return to the hive at night (St. John 2023).

    Here are a few drought-hardy native species that were still blooming and supporting pollinators in my garden on October 10th. All are resistant to deer. Sun, soil and moisture requirements, height, bloom colour and bloom time are noted for each.

    Smooth Aster (Symphyotrichum laeve)

    Full sun – light shade; Sand, loam, clay; Dry to Medium; 4 feet tall; Lavender to light blue; September – October

    Smooth Aster has very frost-hardy flowers that often bloom into early November. The lavender to light blue flowers provide a lavish display. It has an upright form, is salt tolerant, and has the ability to survive drought.

    Given that it blooms into early November, Smooth Aster is an important food source for late season bumble bees. The backdrop of Sugar Maple in full fall colour contrasts nicely with its lavender blooms.

    New England Aster (Symphyotrichum novae-angliae)

    Full sun – Part sun; Sand, loam, clay; Moist-average soil; Tolerates dry soil but may look scraggly; 2-5 feet tall; Purple, pink; August – October

    New England Aster is another late bloomer, often lasting until it is hit by a few hard frosts (Booth nd). It is a clumping perennial that can be divided every 3-5 years and also “politely” seeds into garden gaps. To keep it from flopping over in fertile soils, it can be “Chelsea-chopped” in mid-June to restrict its height. It is an important nectar plant for migrating Monarch butterflies, as well as a larval host for 5 butterflies and more than 40 moth species (Booth and Gray 2024).

    A male Common Eastern Bumble Bee (Bombus impatiens) sleeping on New England Aster blooms.

    Zig Zag Goldenrod (Solidago flexicaulis)

    Part shade to Full Shade; Prefers, fertile loam but tolerates heavy clay; Well-drained soils; 1-3 feet tall; Yellow; August – October

    Zig Zag Goldenrod is a non-aggressive goldenrod that is a great addition to the shade garden. It provides pollen and nectar for both short- and long-tongued bees, wasps, flies and butterflies and it is the larval host plant for over 45 species of moths (Booth and Gray 2024).

    The leaves of Zig Zag Goldenrod can also change colour in fall, adding to the plant’s aesthetic value.

    Blue-stemmed Goldenrod (Solidago caesia)

    Part shade to Full Sun; Most well-drained soils, tolerates poor soil; 1.5 – 3 feet tall; Yellow; August – October

    Blue-stemmed goldenrod has yellow clusters of flowers that bloom all along the purplish-blue stem in early autumn, creating streaks of gold if planted in large patches. Unlike other goldenrods, it does not spread aggressively. Its leaves host larvae of 45 moth species (Gray and Booth 2024).

    Common Eastern Bumble Bee on Blue-stem Goldenrod.

    Button Blazing Star (Liatris aspera)

    Full Sun; Dry-Medium; Sand, loam; 2 – 5 feet tall; Yellow; August – October; Purple-Pink

    Button Blazing Star is one of the most drought tolerant blazing stars. Unlike Dense Blazing Star (Liatris spicata) its flowers are held on individual stems rather than in spikes and the corms cannot be divided. Birds especially prefer its seeds (Diboll and Cox 2023).

    Button Blazing Star provides nectar to migrating Monarchs in my garden on Sept. 2. It was still blooming on October 10th.

    The evening of October 9th we had a second hard frost (-6oC with wind chill) but the next day all of these native perennials were still blooming. If you are looking at your garden this Thanksgiving and not seeing any plants still flowering and supporting pollinators, maybe make plans to add one or two of these next spring?

    REFERENCES

    Booth, S. no date. Native Asters for Ontario Gardens.

    Diboll, N. & H. Cox. 2023. The Gardener’s Guide to Prairie Plants. The University of Chicago Press. 636 pp.

    Gray, R. and S. Booth. 2024. The Gardener’s Guide to Native Plants of the Southern Great Lakes Region. Firefly Books. 352 pp.

    St. John, K. 2023. A Closer Look at Sleeping Bumblebees. Outside my Window blog post.

    The Xerces Society. 2025. Bumble Bees: Nesting and Overwintering.

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    Can You Help our Most Effective Pollinator?
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    Fall Colour in Your Garden
    The Late Summer/Fall Garden
    Bees & Pollinators, Insects, Websites

    The Secret Life of the Eastern Bumblebee

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    By Thom Luloff, Master Gardener in Training

    On a warm spring morning in Ontario, a familiar hum drifts through the air. Low, steady, and purposeful, it comes from a black-and-yellow visitor weaving between garden blossoms—the Eastern Bumblebee (Bombus impatiens). To most of us, it’s a sign of summer’s return, but beneath that fuzzy exterior lies a fascinating story of evolution, resilience, and quiet importance.

    Bumblebees belong to the genus Bombus, a group that diverged from honeybee ancestors around 25 to 40 million years ago (Hines, 2008). Unlike honeybees, which thrive in massive colonies, bumblebees are social but live in smaller, more seasonal groups. The Eastern Bumblebee has evolved as a master of cool and temperate climates, thanks to its thick fuzz and the ability to generate heat by vibrating its flight muscles—a survival skill that lets it fly on chilly mornings when other pollinators remain grounded (Heinrich, 2004).

    Every spring, the story begins anew with a solitary queen who has survived winter hibernation beneath leaf litter (leave the leaves!) or soil. Emerging hungry, she forages for nectar and pollen while searching for a suitable nest site—often an abandoned rodent burrow or a hollow beneath grasses. There, she lays her first clutch of eggs, which hatch into female workers. These workers soon take over foraging, allowing the queen to remain in the nest and focus on laying eggs (Colla et al., 2011). As the colony grows through summer, new males and future queens are produced. Mating occurs in late summer and early fall, after which the old colony dies, leaving only the fertilized young queens to overwinter and begin the cycle again the following year.

    Eastern Bumblebees are generalist foragers, meaning they visit a wide range of flowers. They sip nectar for energy and collect pollen to feed their larvae. Unlike honeybees, which rely heavily on certain crops, Eastern Bumblebees are flexible, visiting everything from clovers and goldenrods to tomatoes and blueberries (Goulson, 2010). Their unique ability to perform “buzz pollination”—vibrating flowers to release hidden pollen—makes them essential for crops like tomatoes, peppers, and cranberries, which depend on this technique.

    In the grand web of life, Eastern Bumblebees are lynchpins. By transferring pollen as they forage, they ensure the reproduction of wildflowers and food crops alike. This not only feeds people but also supports wildlife, since countless birds and mammals depend on the seeds and fruits that bumblebees help create. In forests, meadows, and city gardens, their work sustains plant communities that form the backbone of biodiversity.

    Despite their adaptability, Eastern Bumblebees face mounting challenges. Habitat loss from urbanization and intensive agriculture has reduced nesting and foraging opportunities. Pesticides—especially neonicotinoids—pose lethal and sublethal risks, impairing navigation and reproduction (Woodcock et al., 2017). Climate change adds another layer of stress, disrupting flowering times and exposing bees to extreme weather (Kerr et al., 2015). 

    The Eastern Bumblebee may be small, but its impact is enormous. With every hum in your backyard or park, it carries the story of millions of years of evolution, a seasonal cycle of resilience, and a vital role in keeping our ecosystems alive. Protecting them means protecting the beauty and abundance of the natural world.

    References

    Colla, S. R., Richardson, L., & Williams, P. H. (2011). Guide to the Bumble Bees of North America. Princeton University Press.

    Goulson, D. (2010). Bumblebees: Behaviour, Ecology, and Conservation. Oxford University Press.

    Heinrich, B. (2004). Bumblebee Economics. Harvard University Press.

    Hines, H. M. (2008). Historical biogeography, divergence times, and diversification patterns of bumblebees (Bombus). Systematic Biology, 57(1), 58–75. https://doi.org/10.1080/10635150801898912

    Kerr, J. T., Pindar, A., Galpern, P., et al. (2015). Climate change impacts on bumblebees converge across continents. Science, 349(6244), 177–180. https://doi.org/10.1126/science.aaa7031

    Woodcock, B. A., Bullock, J. M., Shore, R. F., et al. (2017). Country-specific effects of neonicotinoid pesticides on honey bees and wild bees. Science, 356(6345), 1393–1395. https://doi.org/10.1126/science.aaa1190

    Bees & Pollinators, Drought, Heat, Vegetable Gardening

    Hot News in the Vegetable Garden

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    by Lois Scott, Master Gardener

    Excessive heat can certainly make it hard for me to work in the garden.  It can also affect how your vegetables work.

    For most plants ideal growing temperatures range from 15 to 30 degrees Celsius (C).  When temperatures are above 32 degrees C for long periods of time plant growth is slowed and some plants will begin to show stress.  This link describes a number of heat-related issues and some solutions. 

    A neighbour and new gardener commented that he wasn’t getting any fruit forming on his only squash plant and wondered if he had a plant with only female or male flowers.  I reassured him that squash plants and other cucurbit vegetables like cucumber and zucchini all produced male and female flowers on the same plant. 

    While this is true, apparently daytime temperatures of 32 degrees C and up and night time temperatures of over 21 degrees C can change the ratio of male to female flowers to more male than female flowers.  These same temperatures can also cause flowers and small fruit to drop.  Too much or too little water can also cause flowers and fruit to drop. 

    Watering may be within our control but temperatures may not be!  There are varieties that are touted to be heat tolerant and could be a good option for our increasingly hot summers.

    Another cause of no fruit or deformed fruit is poor pollination.  Apparently, many bees don’t like to work when it’s hot.  Temperatures over 32 degrees C causes many bees to slow down and pollinate less. 

    Tomatoes may also be affected by very hot weather.  During hot spells with daytime temperatures above 29 degrees C and night time temperatures above 21 degrees C, tomato plants may become stressed, depleting the plants energy stores and changing the flower making it harder for them to be pollinated.  The flower will then drop from the plant.

    Heat may also keep your tomatoes from turning red.  Tomatoes ripen in two stages.  They are green, seeds form, the area around the seeds becomes soft and gelatinous and they are mature.  Then they turn red.  The ideal temperature for turning red is 20 to 25 degrees C. The pigments that turn mature tomatoes red are not produced when the temperature is above 29 degrees C. 

    The good news is that when the temperature is ideal, they will turn red. More here.

    Gardening provides lots of learning opportunities to improve outcomes but sometimes the weather gets in the way!

    Bees & Pollinators, Insects

    Can You Help our Most Effective Pollinator?

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    By Silvia Strobl, Master Gardener

    Pollinator insects – bees, wasps, beetles, flower flies, ants and butterflies–play an important role in the production of almost 75% of global food crops (FAO 2018). For example, only the tiny chocolate midge is able to pollinate flowers of the cacao tree and produce cacao pods! But bees, including native bees, are responsible for the biggest share at 35% of global food production (Ritchie 2021), including economically important commercial crops such as apples and blueberries! 

    Bees are such effective pollinators because of the specialized hairs and pollen carrying structures on their legs that enable them to gather and transport pollen. The vast majority of bee pollinators are wild, including over 20,000 species of native bees worldwide and 400 species in North America. In natural ecosystems, bees visit the most plants and have the most interactions with flowers as compared to other insect pollinators (Radar et al. 2020). 

    Bees have specialized hairs and pollen carrying structures as seen in the large filled pollen sacs of this Common Eastern Bumble Bee (Bombus impatiens) collecting nectar and pollen on native Shrubby St. John’s-wort (Hypericum prolificum). 

    I enjoy photographing the busy native Bumble Bees in my garden that collect pollen from a wide variety of flowers, often late into summer evenings. Here are a few species that you may see, too. 

    This Yellow-banded Bumblebee (B. terricola) with its distinct yellow and black abdominal band pattern is collecting nectar and pollen from the native Virginia Mountain Mint (Pycnanthemum virginianum). This species is ranked as “Special Concern” in Ontario, meaning it is not endangered or threatened, but may become threatened or endangered due to a combination of biological characteristics and identified threats. Its nests are often underground in abandoned rodent burrows or decomposing logs.
    Here the Perplexing Bumblebee (B. perplexus) is collecting nectar and pollen from native Anise Hyssop (Agastache foeniculum). As its name suggests, this bumble bee can be rather perplexing to identify! As it’s not very common, rather little is known about it.
    The Brown-belted (B. griseocollis) is a short-tongued Bumble Bee and native Butterfly Milkweed (Asclepsis tuberosa) is just one of the flowers it prefers. It is one of the most abundant and widespread bumble bees in northeast North America.

    You can find excellent guides to help you identify the bumble bees in your garden here and you can learn more about native bees in this excellent publication.

    Sadly, all pollinators are experiencing alarming declines due to habitat loss, pesticide exposure, invasive species, parasites/diseases and climate change. One study found that when compared to 125 years ago, 30% of plant:pollinator associations have been lost (Mathiasson and Rehan 2020).  Five Bumble Bee species, American, Gypsy Cuckoo, Rusty-patched, Suckley’s Cuckoo, and Yellow-banded, are currently listed as Endangered, Threatened or Special Concern in Ontario.

    Gardeners Can Help!

    Gardeners can help native bees by creating habitat, providing floral resources and maintaining a pesticide-free garden:

    1. Nesting & overwintering habitat 
    • Most native bees (60-70%) nest in the ground. Use a thin layer of mulch and avoid using landscape paper/fabric which prevents bees from making a nest in the ground.
    • Leave some scrubby areas in your garden for bees
    • For the 30-40% of stem nesting bees, cut back perennials later in spring leaving those with hollow stems at varying lengths (20 to 60 cm) as shown in this excellent guide. If you do cut, leave the bottom 20 cm in place, bundle the cut stems, and place them in your garden.
    An entrance hole of a bumble bee ground nest in a patch of native Pussy Toes (Antennaria neglecta) in the author’s garden.
    1. Floral resources
    • Plant a diversity of native and non-native plants to have continuous blooms, and sources of nectar and pollen, from early spring to late fall
    • Include at least one native early spring blooming shrub or tree (e.g., willow, redbud, cherry) for emerging queen bees
    1. Pesticide-free habitat
    • Avoid using pesticides. Recent research from the University of Guelph has shown that ground-nesting native bees experience reduced pollen collection, induced hyperactivity or decreased number of offspring emerging per nest even when so-called “bee-safe” pesticides were used (Rondreau and Raine 2024).

    Your habitat restoration efforts, especially adding native flowering plants, will go a long way to helping our native bee pollinators, and also our food security.

    References

    FAO. 2018. Why bees matter. https://openknowledge.fao.org/server/api/core/bitstreams/0f47dba8-ab04-4968-a2bc-8a9c06218653/content

    Mathiasson, M.E. and S. M. Rehan. 2020. Wild bee declines linked to plant-pollinator network changes and plant species introductions. Insect Conservation & Diversity. https://resjournals.onlinelibrary.wiley.com/doi/abs/10.1111/icad.12429

    Radar, R., S.A. Cunningham, B.G, Howlett, and D.W. Inouye. 2020. Non-bee insects as Visitors and Pollinators of Crops: Biology, Ecology, and Management. Annual Reviews Vol. 65:391-407. https://www.annualreviews.org/content/journals/10.1146/annurev-ento-011019-025055

    Ritchie, H. 2021. How much of the world’s food production is dependent on pollinators? Retrieved from: https://ourworldindata.org/pollinator-dependence

    Rondreau, S. and N.E. Raine. 2024. Single and combined exposure to ‘bee safe’ pesticides alter behaviour and offspring production in a ground-nesting solitary bee (Xenoglossa pruinosa). Proceedings of the Royal Society Biological Sciences. https://royalsocietypublishing.org/doi/10.1098/rspb.2023.2939