Bees are among the planet’s most important organisms, performing the biological service of pollination that sustains both natural ecosystems and agricultural food production. Understanding the resources that support their survival is a practical way to encourage their populations. The needs of bees extend beyond floral rewards, encompassing shelter, water, and specific nutrients that contribute to the health and reproduction of diverse species. Providing a stable environment that meets these fundamental requirements supports native and managed bee populations.
Floral Preferences for Nectar and Pollen
Bees select flowers based on sensory cues, with color being the most immediate attractant. They possess a sophisticated vision system sensitive to the ultraviolet range, allowing them to see patterns invisible to the human eye that act as “nectar guides.” Bees are particularly attracted to colors in the blue, violet, and yellow spectrum, which stand out sharply against green foliage.
The shape of a flower also significantly influences which bee species can access its resources. Short-tongued bees, such as native solitary species, prefer shallow, open-faced blossoms that provide easy access to pollen and nectar. In contrast, long-tongued bees, like certain bumble bees, are adapted to forage efficiently from tubular flowers where nectar is stored deeper within the corolla. This specialization reduces the bee’s foraging energy expenditure.
Beyond visual appeal, chemical cues in the form of floral scent guide bees over long distances. Fragrance is composed of volatile organic compounds that signal the presence of nectar and pollen, which is helpful when flowers are obscured by dense vegetation. Nectar provides the necessary carbohydrates for energy, while pollen supplies the essential proteins, lipids, and vitamins required for larval development.
A continuous supply of these resources throughout the growing season is necessary to support bee populations from spring emergence through fall. Planting a succession of different species ensures that food is available across the entire active period of the bees. This strategy, known as succession planting, supports a wider variety of bee species whose foraging periods may not overlap.
Essential Non-Food Resources
While flowers provide the primary food source, bees also require non-floral elements, most notably water. Bees use their proboscis to lap up water, which is stored in their crop for transport back to the nest or hive. They cannot drink from deep, open water sources, so they seek out shallow spots to land, such as damp earth, muddy puddles, or the edges of ponds with exposed stones.
Water is used within the colony for several purposes, including regulating temperature through evaporative cooling during hot weather. Worker bees spread a thin layer of water inside the hive and fan their wings to create a natural air conditioning system. Water is also incorporated into the food fed to developing larvae, such as royal jelly.
Bees frequently prefer “dirty” water sources because they contain dissolved minerals and salts. They seek out trace elements like sodium, potassium, and magnesium, often found in damp soil or mineral-rich mud. This mineral collection is important during periods when their diet is less varied, such as in the fall when pollen nutritional content may be lower.
Housing and Habitat Requirements
The majority of native bee species, approximately 70%, are ground nesters, requiring access to bare or lightly vegetated soil to excavate their homes. These solitary females dig individual burrows, often in sunny, undisturbed locations with good drainage. They create a central tunnel and lateral cells for their offspring. Leaving patches of open soil, rather than covering all ground with mulch or dense plantings, directly supports these widespread species.
The remaining native bees are cavity nesters, utilizing existing holes and hollow spaces for reproduction. These bees use natural materials to construct their nests, dividing the cavity into a linear series of cells. Mason bees are named for their use of mud to seal and separate cells, while leafcutter bees use precisely cut pieces of leaves for the same purpose.
Cavity nesters commonly use hollow plant stems, abandoned beetle tunnels in dead wood, or the sheltered spaces of abandoned rodent burrows, which are favored by bumble bee queens. Providing materials like pithy stems, untreated wood blocks with pre-drilled holes, or simply leaving dead wood to decay naturally offers suitable nesting sites. Protecting these sheltered, undisturbed areas supports the next generation of pollinators.