A bee house, often called a bee hotel, is a structure that provides nesting sites for solitary native pollinators, such as mason and leafcutter bees. Unlike honeybees that live in large, social colonies, these bees nest alone in tunnels where they lay their eggs and provision them with pollen. Successfully attracting these insects requires deliberate placement and maintenance of the house, along with ensuring the surrounding habitat meets their specific biological needs.
Selecting the Ideal Location and Timing
The physical placement of the bee house is the first step in creating an attractive nesting environment. Solitary bees are cold-blooded and rely on the sun’s warmth to become active enough for foraging and nesting. Therefore, the house must be mounted to face between southeast and east, capturing the gentle warmth of the morning sun. This orientation allows the bees to warm up and begin work earlier, while protecting the developing brood from the intense rays of the afternoon sun.
The structure should be mounted securely to a stable, fixed surface like a fence, wall, or sturdy post. The house must not swing or sway in the wind, as movement will deter bees from using the nesting tubes. An ideal height is between five and seven feet off the ground, which offers protection from ground-level moisture and helps deter predators like mice. Placing the house under a slight overhang, such as an eave, also provides shelter from heavy rain, keeping the nesting tunnels dry.
Timing the installation is based on the emergence of the earliest occupants. Mason bees are active in early spring, coinciding with the bloom of fruit trees and other early flowers. The house should be placed outside before temperatures consistently reach 50°F to ensure it is available when adult bees emerge from their winter cocoons and begin seeking new nest sites. Leafcutter bees will emerge later in the summer when temperatures are consistently higher, utilizing the same structure.
Providing Essential Nesting Resources
Once the bee house is optimally placed, the surrounding environment must provide the materials necessary for nesting and survival. Solitary bees have short foraging ranges, meaning that pollen and nectar sources must be readily available within a few hundred feet of the house. Mason bees, being early spring fliers, rely heavily on early-blooming native plants and trees like willows, fruit trees, and dandelions. Leafcutter bees, which are active later in the season, require summer-blooming flowers for their pollen and nectar.
It is beneficial to have a continuous succession of native, pollen-rich flowers blooming throughout the spring and summer months. This consistent food supply ensures both the early mason bees and the later leafcutter bees have ample resources to provision their young.
Beyond food, these bees require specific materials to construct the partitions between their egg cells. Mason bees are named for their use of moist clay or mud to build the internal cell walls and cap the entrance of their completed nests. If your environment lacks naturally moist, clay-rich soil, you can create a small, muddy patch within about 50 yards of the house. Leafcutter bees use their strong mandibles to cut semicircular pieces of soft, non-hairy leaves, such as roses or lilacs, to line and seal their nesting tubes.
Maintaining the Structure’s Appeal
Long-term success depends on the regular maintenance and hygiene of the nesting structure. Solitary bees are less likely to occupy tunnels that are soiled or harbor pests and pathogens. Therefore, it is important to use removable and replaceable nesting materials, such as cardboard tubes, paper liners, or natural reeds, rather than permanent drilled holes in wood blocks. These removable tubes should be at least six inches long to encourage the production of female offspring.
The annual process of cleaning and harvesting cocoons is necessary to prevent the buildup of diseases like chalkbrood and to manage parasitic wasps and mites. In late fall or early winter, once all bee activity has ceased, occupied tubes should be removed and stored in a sheltered, unheated location to protect developing cocoons from weather and predators. In early spring, cocoons are placed near the house for emergence, and old tubes are replaced with fresh, clean ones, ensuring a healthy start for the new generation.
Protection from predators is also a maintenance concern to preserve the nesting population. Birds, particularly woodpeckers and nuthatches, may attempt to pull cocoons out of the nesting tubes. A simple solution is to attach hardware cloth or chicken wire with a half-inch grid size over the front of the bee house. This mesh allows the bees to easily enter and exit the nesting tubes but physically blocks larger predators from accessing the cocoons.