Gardening: Boost yields with a home for bees

Some of the most efficient pollinators are bees. There are a few things you can do to attract and keep these critters in your garden.

A good example of a bee house. Saskatoon

Share Adjust Comment Print

The yields of your strawberry, tomato, pepper and other fruits and vegetables may not be what you hoped for. And yet, you’re doing everything right: watering, fertilizing, controlling pests and weeding. Perhaps the problem is you don’t have enough pollinators to fertilize your flowers.

Some of the most efficient pollinators are bees. There are a few things you can do to attract and keep these critters in your garden.

First, you needn’t worrying too much about literally getting stung by inviting wild bees to your yard and garden. There are broadly two types of bees — those that live in colonies (e.g. honey bees) and solitary bees. The colony type can be aggressive and will protect themselves and their colony by stinging perceived attackers. The solitary bees, on the other hand, are much less aggressive and very unlikely to sting anyone. Instead of living in colonies, depending on the species, they will create individual cells for their larvae in the ground, decaying trees, or hollow stems of dead canes (hence ‘solitary’). It is these solitary bees that you want to attract to your yard.

To attract bees to your yard, start by planting a bee-friendly garden, one that is in continuous bloom from early spring to late fall. Avoid growing double flowering varieties. They may be showier than their single flowering sisters, but they typically have less nectar (the bees’ reward for working so hard for you) and pollen is more difficult to access. Include a bee-bath so they have access to water: a shallow container filled with large pebbles or sticks (something for the bees to land on) up to the water level. Keep the water topped up and change regularly to keep fresh.

Now that you’ve taken care of their food and water needs, like all animals, bees need shelter. Tube- or tunnel-dwelling solitary bee species will happily create their solitary nests in a bee house. These can be purchased or made in your workshop. And despite their classification as solitary, leaf cutter, mason and other solitary bees will happily create their solitary nests close to one another.

Whether purchased or homemade, make sure your bee house provides the following:

— Protection from the rain — needs a roof overhang.

— Made from untreated wood (i.e. not pressure treated): large diameter dry branches or logs, lumber scraps or hollow bamboo stems.

— A variety of hole sizes, 2-10 mm (~1/16-3/8 inch), to suit different species. Depth can vary but at least the length of your drill bit (~ 5 cm or 2 inches).

— Holes have a smooth entrance and interiors (no splinters).

— Holes must have a solid back (not open-ended wind tunnels).

Bee houses should be placed in the open, in full sun (east or south) and at least a meter (3 feet) off the ground. Make sure to securely anchor/attach your bee house so it does not swing or sway in the wind.

Adult solitary bees do not overwinter. Instead, what overwinters are the pupae in the tubes/tunnels. It is wet more than cold that is their enemy. To help them survive and keep them dry, move your bee house to a dry, unheated shed or garage, no warmer than 10°C. As soon as it starts to warm in the spring, put your bee house back outside.

Replace your bee house every two years in mid-summer after the latest generation emerges to avoid the build-up of moulds, mites and other pests.

If you have trouble attracting solitary bees to your yard, you can ‘cheat’ a little by purchasing leaf cutter bee larvae from backyardpollinator.ca, a Saskatchewan online company. There is also great information elsewhere online about bees and plans for making your own bee house.

 

Erl gardens in Saskatoon and tweets about it on occasion @ErlSv.

This column is provided courtesy of the Saskatchewan Perennial Society (SPS; saskperennial@hotmail.com ). Check our website (saskperennial.ca) or Facebook page (facebook.com/saskperennial) for a list of upcoming gardening events: Garden Tour, July 14, 2019, 2 p.m., 238 Brightwater Way.

Comments