A diverse array of pollinators supports the countless species of flowering plants that fill up our gardens, agricultural fields, and natural ecosystems. Unfortunately, bees tend to get all the credit and concern. Read on to learn about the non-bee pollinators that work their magic on the plants in your garden.
Why Is Pollinator Diversity Important?
By now everyone knows how important pollinators are to the survival of nearly all species and systems on Earth. Roughly 80% of the plants on our planet produce flowers, seeds, and fruit as a means of reproduction.
The presence of multiple types of pollinators is important because plants have developed relationships with different pollinators to increase the chance of their pollen grains landing on the right mates. Pollinators also have an incentive to be loyal – a closer relationship means their plant of choice is likely to be full of pollen and nectar. Plants can still be visited by multiple different types of pollinators but their unique color, shape and/or scent makes them a priority to their favorites.
Flowers with blue and violet petals are especially attractive to bees, while hummingbirds prefer red. Very bright orange, pink and red flowers are most attractive to butterflies. Night-blooming flowers tend to be white and are pollinated by nocturnal creatures like moths and bats.
Flower shapes have also evolved to accommodate specific pollinators. Deeper flowers are meant for pollinators with long tongues or beaks, like hummingbirds and some butterflies. Flowers with shorter petals or petals that fold back can be pollinated by ones with shorter tongues or beaks, like bees. If a flower has a very unusual or complex shape it’s likely that the plant has a close relationship with a specific pollinator.
If you plant a wide variety of plants in your garden, you will notice many different types of pollinators among them.
Beetles
Beetles were some of the first pollinators, pre-dating the evolution and emergence of bees. Fossil records demonstrate bees visiting flowers about 200 million years ago. While beetles are estimated to help pollinate about 90 per cent of the world’s flowering plants, they aren’t primary pollinators for most of the plants that grow in temperate regions.
Some of today’s beetles that pollinate flowering plants include tumbling flower beetles, soldier beetles, and checkered beetles. You’re likely to spot beetles in your garden at any time, since there’s such a wide range of species with different shapes, sizes, and preferences for plants.
There are, however, invasive beetles like the Japanese beetle that should be eradicated from your garden. Some gardeners dislike beetles in general, since some unfortunately tend to chew through and defecate on plants as they pollinate.
Wasps
Wasps share several physical characteristics with bees but lack the fuzzy hairs that trap pollen grains. The smoothness of wasp bodies makes them a less effective pollinator, but they still move pollen around as they move from plant to plant to drink nectar. Fig trees (Ficus carica) are exclusively pollinated by fig wasps.
Wasps are beneficial in gardens because they hunt other insects that could harm your plants, such as aphids, hornworms, cabbageworms, and tent caterpillars. They use their stingers to capture insects and spiders as food for their larvae. Just make sure you steer clear from any wasp nests!
Most wasps do not have stingers. Even the dreaded yellow jacket rarely stings away from their nest, provided you don’t make it mad.
Flies
Flies are incredibly important pollinators, second only to bees. They help pollinate hundreds of different food crops, as well as ornamental plants. Like wasps, most flies lack pollen-trapping fuzz, though some “bee mimics” like bee flies, are hairy.
Some species of flies have close relationships with a specific plant, while others are generalists. Plants that have putrid odors, like decomposing plant or animal material, are most likely involved with fly pollination. It’s even a common tactic for mango farmers to place containers full of roadkill among their trees to attract fly pollinators.
Butterflies
Butterflies are considered a “charismatic” pollinator, unlike beetles, wasps or flies. They are valued for both their striking beauty and their role as pollinators for many edible and ornamental plants. Most of the staple vegetables and herbs in the brassica, carrot, mint, legume, and sunflower families rely on butterfly pollination to produce seeds for the next generation of plants.
Butterflies sit on the edge of flowers and extend their long tongues into them to drink nectar. Pollen attaches to their feet and wings and disperses to other flowers as they search for more nectar.
Unfortunately, multiple butterfly species have been declining in recent years. Gardeners have taken to planting species that attract and support butterflies, such as butterfly weed (Asclepias tuberosa), swamp milkweed (Asclepias incarnata), butterfly bush (Buddleja davidii) and the purple coneflower (Echinacea purpurea). Butterflies also love flowering trees like crab apples (Malus).
Moths
Moths pollinate flowers similar to butterflies, though they generally feed at night rather than during the day. Moths tend to visit the same night-blooming flowers as bats, some of which only open at night to become more fragrant to nocturnal pollinators. Some plants, like yucca, depend on specific species of yucca moths to perpetuate future generations.
White or very lightly colored flowers are easily spotted by moths in the dark. Artificial lighting at night is starting to interfere with nocturnal pollination, so if you decide to plant a night-blooming garden for moths it’s best to do so away from any lighting.
Ants
Ants often visit low-growing flowers to collect energy-rich nectar or to hunt other insects, accidentally pollinating plants as they crawl from bloom to bloom.
Ants are generally not good pollinators, despite their abundance and diversity. They tend to secrete anti-microbial substances that end up killing pollen grains and they only forage short distances from their nests, so pollen grains aren’t transported over long distances.
There are cases of plants that have adapted to ant pollination because of a lack of other pollinators, such as low-growing succulents in harsh drylands. Other plants prefer to use ants to defend them from herbivorous insects, rather than as pollinators, by secreting nectar from glands outside of the flowers.
Birds
Birds are another charismatic pollinator that people are happy to attract to their gardens. The most famous of them are hummingbirds, but there are roughly 2000 bird pollinators around the world. Birds like honeyeaters and sunbirds are especially important for tropical fruit production.
Birds pollinate flowers by dipping their beaks deep into flowers to drink the nectar. The pollen grains stick to the bird’s bill and gets deposited into the next flower it visits. In flowers with both male and female parts, a hummingbird nudging the flower or flying near it can result in pollination.
To attract bird pollinators, try plants that are bright red, orange or yellow with deep, tubular flowers that produce copious amounts of nectar like honeysuckle (Lonicera), trumpet flower (Campsis radicans), and red hot poker (Kniphofia spp.).
Bats
Bats are nectar lovers that pollinate hundreds of different plants around the world and are important pollinators of tropical and Southern plants like mango, bananas, cashews, almonds, cacti, and agave. They are nocturnal and prefer night-blooming species with large, light-colored, and sweet-smelling blooms with tubular shapes.
While bats are not major pollinators in temperate regions, you can attract them with night-blooming plants, such as night-blooming jasmine (Cestrum nocturnum) and honeysuckle (Lonicera spp.). Bats will also eat nocturnal insects that would otherwise eat these plants. Some bat enthusiasts even install bat houses to help local bat populations.
There are many other animals that pollinate plants besides bats and birds. The list continues to grow with the interest in non-bee pollinators. Some of the cutest include Cape Rock sengis, black and white ruffled lemurs, honey possums, and large-spotted genets. Even reptiles have been found to pollinate specialized blossoms. Humans are also taking up the pollination mantle in the face of declining pollinator populations and the need for efficient food production.
Written by: Marika Li
