Bringing Back the Bees

Photo by Ted Kropiewnicki.

Bringing the bees back can be as simple as 1…2…3

STEP 1:  Choosing the Right Flowers

Providing a range of plants that will offer a succession of flowers and thus pollen and nectar through the whole growing season is most beneficial to bees. This is especially important during foraging times from February to November.

  • Use local native plants. Research suggests native plants are four times more attractive to native bees than invasive species. In gardens heirloom varieties of herbs and perennials can also provide good foraging. A plant list with bloom times is provided.

  • Choose several colors of flowers. Flower colors that particularly attract bees are blue, purple, white and yellow.

  • Plant flowers in clumps. Flowers planted in clumps are more likely to attract pollinators than individual plants scattered throughout the habitat patch.

  • Include flowers of different shapes. Bees come in all different sizes, have different tongue lengths and will feed on different shaped flowers. Providing a diversity of flower shapes means more bees will benefit.

  • Have a diversity of plants flowering all season. By having several plant species flowering at once, and a sequence of plants flowering through spring summer and fall you can support a range of bee species that fly at different times of the season.

Please view our Native Plants and Bloom Phenology and Non-Native Plants and Bloom Phenology documents for more information.

STEP 2:  Recognize and Protect Habitat

Nest sites are a key component of bee habitat.

Ground-Nesting Bees

Most native bees-about 70% nest in the ground, and need access to the soil surface to dig their nest. Each female excavates her own nest tunnel and brood cells, and stocks the cells with nectar and pollen. Where possible, keep bare or partially vegetated ground. Where you can, create more.

  • Bare ground.  Simply clear the vegetation from small patches of level or sloping ground and gently compact the soil surface. These patches can be from a few insects to a few feet across ,but should be well drained, and in an open ground-will draw different bee species, so create nesting patches in different areas if you can to maximize the nesting opportunities.

  • Sandpits and piles. In a sunny, well-drained spot, dig a pit about 2’ deep, and fill it with a mixture of pale-colored, fine-grained sand and loam. Where soils do not drain well, a pile of the sand/loam mixture can help, or make a raised bed. If space is limited, you can fill planter boxes with the sand/loam mixture.

Wood-Nesting and Cavity-Nesting Bees

About 30% of our native bee species make their nests in old beetle tunnels in snags or similar locations. The female bee builds dividing walls across the tunnel to make a line of brood cells. Where you can, retain snags where this is not possible the addition of nesting boxes will suffice. Nesting boxes can be purchased at most gardening centres.

  • Nesting blocks. Bee blocks can be made by drilling nesting holes between 3/32” ’ and 3/8” in diameter, at approximate ¾” centers, into the side of a block of preservative free lumber. The holes should be smooth inside, and closed at one end. The height of the nest is not critical-8” or more is good-but the depth of the holes is. Holes less than ¼” in diameter should be 3-4” deep. For holes ¼” or larger, a 5-6” depth is best.

  • Logs and snags. Get some logs or old stumps and place them in sunny areas. Those with beetle tunnels are ideal. Plant a few upright, like dead trees, to ensure some deadwood habitat stays dry. On the southeast side of each log, drill a range of holes, as outlined above.

  • Stem or tube bundles. Some plants, like teasel, bamboo, and reed, have naturally hollow stems. Cut the stems into 6” to 8” lengths. Be careful to cut the stems close to a stem node to create a tube with one end closed. Fifteen to twenty stem pieces tied into a bundle (with the close ends of the stems together) makes a fine nest. Or, make a wooden frame to make as many stems as you like. Paper tubes can be used as well. Just make sure they stay dry.

Location of the nesting sites is important. These nests should be placed where they are sheltered from the worst of the weather, with entrance holes facing towards east of southeast, so they get the morning sun. With stem bundles, be sure that the stems are horizontal. The nests can be any height from the ground, but between three and six feet is convenient. Put them on a building, fence or stake or place them in a tree. Fix them firmly so they don’t shake the wind.

Bumble Bees

Unlike the nests built for solitary bees there are no strict size requirements for bumble bee nests-any hole large enough for a small colony will be OK. After emerging from hibernation, bumble bees nest in abandoned mouse holes in the ground or under grass tussocks. Where you can, keep patches of rough grass, or consider building a nest box or two.

  • Nest box. A simple wooden box, with internal dimensions of about 7” by 7” by 7”, made from preservative-free-lumbers will work. Drill a few ventilation holes near the top (covered with door screen to deter ants) and some drainage holes in the bottom. Make an entrance tunnel from ¾” plastic pipe, marked out on the outside with a contrasting color, and fill the box with soft bedding material, such as upholsterer’s cotton or short lengths of unraveled, soft string. The box must be weather tight; if not the larvae may become cold in a damp nest, and mold and fungus will grow.

Place the box in an undisturbed site, in partial or full shade, where there is no risk of flooding. The box should be on or just under the ground. If you bury it, extend the entrance tube so it gently slopes up to the surface. Put you nesting box out when you first notice bumble bees in the spring , or when the first willows and other flowers are blooming and be patient. There is no guarantee that bees will use your box. Only about one in four boxes get occupied. If it has no inhabitants by late July, put the nesting box into storage until next spring.

STEP 3:  Leave Toxic Pesticides Behind

Please view our Leave Toxic Pesticides Behind document for more information.