University of Vermont
Department of Plant and Soil Science

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TEN TOP PERENNIALS TO PLEASE POLLINATORS

Annie White, Research Assistant, and
Leonard Perry, Horticulture Professor
University of Vermont
   
Many plants and pollinators have the kind of relationship we all look for in everyday life—one that is mutually beneficial. Pollinators help move pollen to fertilize flowers, and in return, the plant offers the insect a food reward of pollen or nectar or both. Female bees collect the protein-rich pollen from flowers and combine it with nectar to form a food product for their larvae. In addition to bees, other insects like butterflies and wasps visit flowers just to sip on nectar—a sugary energy source. Unbeknownst to them, they also help in a small way to move pollen from flower to flower.

The size, shape, color, and bloom time of flowering plants all influence what types of pollinating insects will visit, so planting a diversity of flowers is the best way to attract a diversity of pollinators. To help support more beneficial pollinators in your gardens and landscape, consider these ten native, and hardy species of perennial plants. All are listed to grow to at least USDA zone 4 (-20 to -30 degrees Fahrenheit average minimum temperature annually).
   
1. Wild Bergamot (Monarda fistulosa).  This native perennial offers nectar and pollen to pollinators during its long mid-summer bloom period. Long-tongued bumblebees are the most frequent visitors to wild bergamot, but hawk moths and hummingbirds also visit to sip on the consistent nectar source. The plant prefers well-drained soils with dry to medium moisture in full to partial sun. Wild Bergamot’s foliage is susceptible to powdery mildew so plant where there is plenty of air circulation and sunlight.
   
2. Purple Coneflower (Echinacea purpurea).  This native perennial is also one of the most popular garden flowers in the U.S. It features showy daisy-like flowers from mid- to late-summer. The large central cone of the coneflower is made up of hundreds of tiny flowers called disc florets. Bees and butterflies can be seen circling around the cone, visiting each floret to sip nectar or gather pollen. These plants are happiest when grown in well-drained soils with dry to medium moisture in full sun. Only those cultivars (cultivated varieties) that are selected from the species may be useful to pollinators.  Many hybrids and double forms may not.
   
3. Culver’s Root (Veronicastrum virginicum).  The towering spikes of a Culver’s root plant provides a nice vertical element in the garden. The tiny white flowers that cover these spikes are most frequented by bees, flies, and butterflies, but are also a favorite of other beneficial insects, including predatory wasps and parasitoids. This perennial prefers moist, well-drained soils in full to partial sun, but will tolerate a variety of soil conditions. The pale purple-flowered cultivar Lavender Towers has proven quite attractive to pollinators.
   
4. New England Aster (Symphyotrichum novae-angliae). This is one of the last flowers to bloom in the fall, making it an essential food source for many pollinators. Because of its abundance of small, purple, daisy-like flowers, both honeybees and pre-hibernation bumblebee queens flock to this aster for the plentiful nectar and pollen. Asters are also the preferred nectar source for many butterflies and moths in the fall. New England asters are easily grown in well-drained soil with medium moisture and full sun.
   
5. Spotted Joe Pye Weed (Eutrochium maculatum).  This bold and statuesque native perennial attracts many bees and butterflies during its mid- to late-summer bloom. Most visitors are seeking out the abundant nectar found in the numerous tiny disc florets clustered on the large flower heads. Wasps, flies, and moths can also be observed visiting the flowers. While the spotted Joe Pye weed prefers wet to moist soils, Joe Pye weed (Eutrochium purpureum) is more tolerant of partial shade and drier soils.
   
6. Anise Hyssop (Agastache foeniculum).  This and other wild hyssops provide long-lasting, nectar-rich summer blooms. This clump-forming perennial features tiny lavender to purple flowers densely packed along upright spikes. Honeybees and bumblebees are the most frequent visitors, both collecting pollen and feeding on nectar. Butterflies and moths also feed on the plant’s nectar. Anise hyssop grows best in well-drained soils with dry to medium moisture and full to partial sun exposure.
   
7. Wild Blue Indigo (Baptisia australis).  Tall spikes covered in deep-purple flowers of this species bloom in late spring, attracting bumblebees and serving as a host plant for some moths and butterflies. Accessing the nectar inside the closed pea-like flowers is challenging for most pollinators, but the size and strength of bumblebees enables them to pry the flowers open and reach the nectar reward. Wild blue indigo grows best in well-drained soils with dry to medium moisture and in full or partial sun.
   
8. Marsh Milkweed (Asclepias incarnata). Marsh milkweeds are rich in nectar and attract pollinators of all kinds with their highly fragrant and showy pink flowers. Milkweeds are also the host plant for monarch butterflies. Marsh milkweed prefers medium to wet soils in full sun. An alternative for drier sites is the orange-flowered butterfly milkweed (A. tuberosa).
   
9. Beardtongue (Penstemon digitalis).   Blooming in late spring, beardtongue’s white tubular flowers are a favorite of small- and medium-sized native bees. Smaller bees like sweat bees and mason bees are well suited for accessing the flower’s hidden nectar and pollen. Bumblebees, honeybees, and flies also visit beardtongue. The plant grows best in dry to medium soils in full sun.
   
10. Sneezeweed (Helenium autumnale).  Do not let this plant’s misleading common name deter you: it really doesn’t make you sneeze! It is a magnet for all insect pollinators late in the season. The bright-yellow daisy-like flowers bloom from late summer to early fall and are especially attractive to honeybees, bumblebees, and butterflies.  Sneezeweed grows easily in medium to wet soils in full sun.

These 10 flowering plants are just a handful of the many tried-and-true native perennials that flourish in New England gardens, and are known to attract and support a variety of pollinators. If you are looking at other perennials or selections of these 10, try mainly native species, and mainly perennials without double or exotic flower types. Be cautious, too, of perennials that have been bred to bloom much of the summer.  This benefit for we human beings often means that the flowers are sterile, perhaps offering few benefits for pollinators.  You can find more pollinator resources and recommendations, including design tips, online; for starters, please visit pollinatorgardens.org.

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