I can count on one hand the number of honeybees that we saw in Marjorie’s garden last year, while native bee species, mason bees and various bumblebees, were abundant. In June the catnip stems were in motion from dawn to dusk as bumblebees danced among the flowers.
At first light we would find bumblebees sleeping on sunflower heads where they spent the chilly night dusted with golden pollen. We would gently stroke their hairy bodies and think them dead, then watch them come to life in the warmth of the first sunbeam.
Depending on these native bees to pollinate our garden plants, we spend the last days of winter preparing their homes, cleaning out the old ones, building new ones. These homes look nothing like a beehive.
Unlike non-native honeybees that live together in hives, mason bees are solitary, each female requiring her own private nest site. Bumblebees are more social, living in underground colonies during the summer, but the number of bumblebees per colony seldom approaches the population size of a honeybee colony. In winter, new bumblebee queens hibernate underground alone to start new colonies come spring.
Female solitary bees lay their eggs in hollow plant stems, such as raspberry canes, or in the holes made by other insects in dead trees and fence posts. The bees bring pollen and nectar to the holes, mix it into the proper-sized lump and lay an egg into it. Then with mud, they fashion a thin but strong cell wall. They continue until all the holes are filled or they run out of eggs. The larvae eat the food, spin cocoons about themselves, and inside the cocoons metamorphose into adult bees. They hibernate over winter to come out in the early spring, mate and start the process over again.
Because the population of solitary bees can be limited by lack of natural nesting sites, placing nesting boxes built from wooden blocks around the garden can increase the numbers of these gentle bees at work there. The boxes should be placed in the garden in early spring, mid-March to late April, since solitary bees start searching for nest sites in May.
Solitary bee nest boxes are easy to make using construction plans available from several Internet sites. Enter “making native bee nest boxes” in your search engine. Adults and older children can do the sawing and drilling while the younger children personalize each box with a drawing done in water-based paint or crayons.
Pay close attention to the placement of your nest boxes, installing them between three and five feet above ground and facing southeast so that the early morning sun warms the nest. And don’t be surprised if your new nest boxes are largely ignored the first year — bees seem to prefer an old fixer-upper.
Providing homes for bumblebees is more a matter of keeping a portion of your garden out of cultivation. While there are several styles of bumblebee nest boxes available commercially, they are rarely used if there is an old mouse or vole hole nearby, or an underground cavity in a clump of grass.
If you want to attract bumblebees, be less tidy in the garden. In Marjorie’s garden where the catnip grows, an old tree stump slowly rots, each year sinking a little deeper into the earth, the holes left by decayed roots providing perfect nests for the bumblebees. They live where they work, a perfect arrangement that reminds me of my graduate school days.
Send queries to Gardening Questions, P.O. Box 418, Ellsworth 04605, or to firstname.lastname@example.org. Include name, address and telephone number.