Providing Habitat for Bumblebees: Gardening With A Big Buzz

Fun Facts:

• Bumblebees are very important pollinators of both wild native plants and agricultural crops.
• Because bumblebees have the ability to fly in cooler temperatures and when it is darker, they will be pollinating flowers earlier and later in the growing season and during the lower light of dawn and dusk.
• This ability is unique to bumblebees, as they are one of the few insects that are able to generate body heat (thermoregulation) and fly when it's cold, allowing them to live in more northern climates and at higher elevations.

The Cornerstone of Pollination

Bees are a cornerstone of nature's system for the pollination and reproduction of flowering plants. Without bees, many of the planet's important web-of-life food plants that feed animals and humans would not exist. Much needed attention has been focused on the plight of the honeybee and Colony Collapse Disorder, but there is also an urgent need to protect our bumblebees. Providing habitat-friendly gardens and landscapes are the most important thing gardeners can do to make a meaningful difference in helping to conserve and protect our native bumblebees and wild bee populations. By understanding their needs and planting to support them with food, we can help to undo what mankind has been inflicting on our wonderful insect friends.

Bumblebees Are Social Creatures

Unlike most native bees, which are usually solitary, bumblebees are social insects that live in colonies. Bumblebee colonies are much smaller than honeybee hives, varying in numbers from 50 to 500 members.

They also have a much different lifespan than honeybees. Honeybees are perennial, with hives surviving the winter on stored honey and pollen. Bumblebee colonies are annual, with individual bees living one season, and only the queen bumblebee surviving through the winter. At the start of spring, she emerges from hibernation to begin foraging and looking for a suitable nesting site where she lays her eggs and re-establishes the colony. (This is an important reason to provide early-season nectar in your garden with flowering shrubs and spring-blooming perennials!)

Habitat Fit For A Queen

Providing undisturbed places for queen bumblebees to nest is a very important part of bumblebee stewardship. The following garden features can be used by a queen bee to establish a nest and shelter her colony: buildings, rock walls or rock piles, abandoned underground burrows, cavities in dead trees, abandoned bird nests and bird nesting boxes. There is much to be learned about the nesting requirements of different bumblebee species, but we know that they can use both natural and man-made structures.

Bumblebees are known to burrow in bare ground; this is why near-surface and subsurface disturbance of the ground by digging, tilling and plowing can be disastrous for bumblebees (and other native bees that also burrow in bare ground).

Don't Forget Ornamental Grass

Native bunch grasses, such as Prairie Switchgrass (Panicum), Indiangrass (Sorghastrum), Dropseed Grass (Sporobolus), Little Bluestem (Schizachyrium - of which we offer several varieties), Big Bluestem (Andropogon), and Grama Grass (Bouteloua) provide nesting sites and protection for the queen to overwinter. Not only do these Ornamental Grasses look great all year round, but they also provide important habitat. 

We highly recommend that gardeners leave our perennial plants and grasses standing over the winter. This is the best reason to hold of on trimming back until late spring, after bees have had a chance to wake up from their winter slumber.

Go Natural And Organic

One of the biggest threats to bumblebees (and all bees) is the use of chemical pesticides. Unfortunately, these toxic chemicals are most commonly associated with lawn care and the lawn care industry — and these toxic compounds are being applied by the ton to the millions of acres of land covered by lawns.

Toxins to avoid: Systemic neonicotinoids are especially harmful and widely sold at the "big box" stores and uninformed nurseries and garden centers. Often overlooked is the use of agricultural chemicals on the soil, such as diazinon to "control" ground-dwelling insects and their grubs, pre-emergent herbicides, and fungicides.  

For so many reasons, if you have a lawn, care for it organically! If you do need to protect your lawn from beetle grubs, the primary target of diazinon, use milky spore, a natural grub control. For above-ground insects, diatomaceous earth is a safe, natural alternative control.

Learning From The Xerces Society

When it comes to insects, The Xerces Society is the go-to organization for good, scientifically-based information on how we can protect our invertebrate (insect) friends. They have an outstanding book all about this incredibly wonderful group of pollinators titled Conserving Bumblebees; Guidelines for Creating and Managing Habitat for America's Declining Pollinators, available online in PDF form. This is the most comprehensive book on bumblebees, and indispensable for learning all about this wonderful group of insects.

The Perennial Question: What's For Dinner?

Bumblebees are generalists when it comes to choosing the flowers they pollinate while foraging for nectar and pollen. They typically prefer blue, purple, pink, and yellow flowers. They're actually color-blind to red flowers (unless the red flowers have ultraviolet markers they can see).

Bumblebees prefer perennial plants as opposed to annuals, more than other native bees and honeybees, as perennials tend to have larger quantities of nectar. See the list at the end of this article to learn the genera of perennial and woody plants that they prefer.

Jump To Our Recommendations: Top Plants For Bumblebees