Maximizing biodiversity in home gardens requires understanding the unique traits of diverse animal pollinators—including bees, wasps, butterflies, moths, beetles, flies, birds, and bats—and cultivating the specific floral features that attract them. Each pollinator plays a distinct ecological role and is drawn to specific shapes, colors, scents, and habitats.
1. Bees: The Premier Pollinators
- Biology and Mechanism: In the United States, there are over 4,000 species of bees, though their populations are currently in decline. Bees are highly efficient because their short bodies are covered in hairs and specialized pockets designed to collect large amounts of pollen. As they busily forage for pollen and nectar to take back to the hive to feed their larvae, they transfer pollen between flowers of the same kind, facilitating cross-pollination. Honeybees alone are responsible for pollinating 130 types of fruits and vegetables.
- Attraction Strategies: To attract bees, gardeners should plant a diverse array of flowers, particularly native species. Bees are visually attracted to flowers that are bright white, blue, or yellow and possess a mild, fresh scent. Key plants include aster, foxglove, bee balm, and black-eyed Susan.
2. Wasps: Sweet-Toothed Insect Helpers
- Biology and Mechanism: Wasps belong to the same order of insects as bees (Hymenoptera) and are also active pollinators. However, unlike bees, they have slender, smooth bodies and longer, thinner legs. Because their bodies are not hairy, far less pollen sticks to them, making them generally less effective at collecting and transferring pollen. The most notable pollinating wasp groups are fig wasps, European wasps, and the common wasp.
- Attraction Strategies: Wasps are highly drawn to sweet smells. Gardeners can entice them by planting species such as spearmint, sweet fennel, Queen Anne’s Lace, or yarrow. Planting flowers with extra nectaries (glands that secrete nectar outside the flower) is another effective way to attract them.
3. Butterflies: Visual and Sunny Foragers
- Biology and Mechanism: Butterflies are widely recognized pollinators whose long, thin legs collect pollen as they feed from flowers. However, they collect less pollen than bees because their body structures do not hold pollen as effectively.
- Attraction Strategies: Butterflies rely heavily on their sense of vision. To attract them, a garden should feature flowers with flat “landing pads” and bright colors like red, yellow, purple, orange, and pink. Examples of appealing plants include lavender, aster, and marigolds. To support them long-term, gardeners must provide host plants where butterflies can lay eggs and where caterpillars can feed. Additionally, gardens should include a wet sand “puddling” spot where butterflies can drink and extract essential minerals, and flat stones placed in the sun so they can bask and warm their wings.
4. Moths: Crucial Night-Shift Pollinators
- Biology and Mechanism: Moths are major pollinators that differ from bees and butterflies by primarily pollinating at night, often visiting plant species that bees do not. While some species like the Luna moth are strictly nocturnal, others like the Hummingbird moth are active during the day.
- Attraction Strategies: To attract moths, plant flowers that are white, pink, or dull red, have an abundance of nectar, and release a strong, sweet scent at night. Examples include jasmine, tobacco, yucca, and morning glory. Gardeners should also avoid excessive hard landscaping (like gravel), cultivate a range of shrubs and grasses for caterpillars, and plant trees like oaks.
5. Beetles: Ancient and Abundant Pollinators
- Biology and Mechanism: Beetles are essential to the global ecosystem, pollinating up to 88 percent of all flowering plants worldwide. Common pollinating beetles include soldier beetles, blister beetles, and soft-winged flower beetles.
- Attraction Strategies: Because beetles consume pollen directly, they require flowers that produce abundant pollen and moderate nectar. They need wide, bowl-shaped flowers with exposed reproductive organs to allow easy access. They are attracted to white and dull green flowers and rely heavily on their sense of smell, preferring odors that range from fruity to rancid. Plant species like magnolias and goldenrod are highly attractive to them.
6. Flies: Weather-Resistant Laborers
- Biology and Mechanism: Though often considered pests, flies—particularly hover flies and blowflies—are the most important pollinators after bees. The hairs on their thorax and head can carry thousands of pollen grains. Flies can travel long distances and are far more tolerant of cold, wet, and windy weather than bees.
- Attraction Strategies: Hover flies are strongly attracted to pollen and nectar. Planting species like wild carrot, sweet alyssum, wild mustard, and Queen Anne’s Lace will invite hover flies to the garden.
7. Hummingbirds: Energetic Day Visitors
- Biology and Mechanism: Hummingbirds have incredibly high caloric needs to sustain their rapid, fluttering flight, requiring them to visit between 1,000 and 3,000 flowers every day. As they drink nectar, they pick up and carry pollen from flower to flower.
- Attraction Strategies: Hummingbirds are easily attracted to bright red, tubular flowers. Key plant species include columbines, cardinal flower, lupine, and trumpet vine. Hanging bright red feeders filled with sweet artificial nectar also helps attract them.
8. Bats: Important Mammalian Pollinators
- Biology and Mechanism: Bats pollinate approximately 500 species of plants, including ecologically and commercially vital species like eucalyptus, bananas, mangoes, and wild agave. This bat-mediated pollination process is called chiropterophily, which occurs as bats carry pollen stuck to their fur to new locations.
- Attraction Strategies: Bats pollinate at night and are drawn to pale, night-blooming flowers with strong fragrances. Helpful plants include thyme, honeysuckle, and evening primrose. Gardeners can also construct tight roosting spaces (bat houses) mounted on a pole at least 12 feet high.