By Pamela Sleightholm
After planting three Joe Pye weed (Eutrochium purpureum) seedlings in my front garden last year, this was the summer I got to reap the rewards of this stunning plant. Without fail, the Joe Pye weed is the centre of the action on a visit to my garden – native bees, butterflies, hover flies, and beetles are always buzzing around its towering pale pink blooms.
The draw is its combination of height, colour, flower shape, scent and extended bloom times. Each of these characteristics evolved alongside native insects, making them a perfect fit for local pollinators.
Height
If left to its own devices, Joe Pye weed can reach an astonishing eight feet! For flying insects, that height is a beacon – the plants are recognisable and easily accessible.
Understandably, this isn’t a plant we recommend for boulevard gardens where sightlines are key! At these heights, it’s a candidate for seasonal privacy plantings – or you can give it a spring Chelsea Chop to keep the height a bit lower.
Colour
Humans may not see pale pink or purple flowers as powerfully vibrant colours – we’re more drawn to red, orange, yellow or bright pink. But insects have different colour perception than humans. Though the highest frequency light we can see is violet, many insects can perceive higher frequency ultraviolet light. And on the lower frequency of the spectrum, humans see red as bright, warning and obvious, but many insects can’t see red at all.
It’s this difference in perception that explains why the pale colours of some native plants are so attractive to pollinators.
If you want to learn more about how insects perceive flower colours and patterns, here’s a great video from Nature Bites with David Attenborough:
Flower Shape
Insects need to be able to reach the nectar and pollen to be able to get their food and pollinate! Joe Pye weed's blooms are grouped on big, round umbels (almost shaped like an umbrella). The umbels provide enough room for large insects to land and stand on while feeding, and the anthers of each flower (where the pollen is located) are easily accessible.
Scent
On July days when Joe Pye weed first comes into bloom, its warm vanilla scent is another sensory pull on pollinating insects.
Bloom Times
Planning for three seasons of blooms is one of the most important considerations for habitat gardens. For early emerging insects, we plant early blooming perennials, trees and shrubs. Likewise, for those whose life cycles extend from summer into the cooler autumn months, having late summer and early fall blooms like Joe Pye weed, asters and goldenrods is crucial.
And when the blooms are done birds like American goldfinches will feast on the seeds and Joe Pye weed’s hollow, pithy stems will shelter cavity nesting bees like leafcutter bees (Megachilidae spp.).
It’s just one species, but it packs a punch! Joe Pye weed is a towering beauty that will support a range of biodiversity in the garden right into the fall! And if you're curious about the name, it's thought that "Joe Pye" is the anglicized spelling of "Zhopai", an Indigenous medicine man who used the plant to cure an outbreak of Typhoid fever (https://www.mohican.com/joe-pye-weed/, https://www.nytimes.com/1993/09/12/nyregion/gardening-how-joe-pye-gave-his-name-to-a-weed.html).