How to Plant and Grow Hollow Joe-Pye Weed | Gardener’s Path

Eutrochium fistulosum

Hollow joe-pye weed, Eutrochium fistulosum (syn. Eupatorium fistulosum) is a flowering perennial in the Asteraceae family suited to cultivation in USDA Hardiness Zones 4 through 8.

It is native to eastern regions of North America, thriving in the full sun to partial shade of low-lying wetlands.

This impressive species reaches heights of four to seven feet and is distinguished from other Eutrochium varieties by its whorled arrangement of large leaves and distinctive hollow stems that may show purple coloring but lack spots.

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From midsummer through fall, it produces branching clusters of mauve, vanilla-scented flowers that attract bees, butterflies, and other beneficial pollinators.

The robust seed heads that follow provide valuable late-season food for migratory songbirds, including goldfinches and juncos.

In our guide to growing joe-pye weed, we cover how to cultivate wildflowers in the Eutrochium genus.

This article zeros in on hollow joe-pye weed, E. fistulosum. Here’s what I’ll cover:

Also known as trumpetweed or purple thoroughwort, E. fistulosum is an easy-care plant that expands its presence annually through rhizomatous spread and self-seeding.

It also serves as an effective erosion control plant in moist soils.

Hollow joe-pye weed is a substantial addition to the home landscape with its upright, clumping growth habit and mature width of two to four feet.

How to Grow

In its native eastern North American habitat, E. fistulosum grows in moist conditions, enduring hot, humid summers and cold, snowy winters.

It has poor drought tolerance, and leaves will scorch when water is insufficient.

Light

Plants perform best in full sun but tolerate partial shade, though stems may become leggy with sparse foliage in shadier conditions.

Soil

The ideal growing medium is moist, fertile loam with a slightly acidic to slightly alkaline pH of between 6.0 and 8.0. Soil should be well-draining and moisture-retentive.

Plants will tolerate lower-quality soil as long as it remains consistently damp and can withstand periods of flooding.

Conduct a soil test to assess fertility and amend as needed with organic matter such as compost.

Water

Plants require consistent moisture to thrive and prefer “wet feet,” similar to irises. During dry periods, water weekly to prevent the soil from drying out.

Water when the top two inches of soil is dry.

Fertilizing

When grown in fertile soil that mimics its native habitat, E. fistulosum requires no additional fertilization.

To compensate for poor soil conditions, you can apply a slow-release granular fertilizer in spring.

Where to Buy

You can generally find the species plant available at nurseries that stock a good range of natives.

Alternatively you can shop online.

Hollow Joe-Pye Weed Seeds

Hollow joe-pye weed seeds are available from Smoke Camp Crafts via Amazon.

Each package contains approximately 1,000 seeds.

There are a few cultivated varieties available, including ‘Alba’ which sports white flowers and ‘JoJo,’ a compact cultivar with mature dimensions of three to four feet tall and two to three feet wide.

‘Jojo’ has bright pink double blooms with twice the number of petals as the species. This cultivar is sterile, so plants do not self-sow.

Maintenance

Native joe-pye weed is a low-maintenance perennial requiring only basic seasonal care.

Tall stems may need staking for support, particularly in windy locations or rich soils that promote vigorous growth.

Some gardeners use the Chelsea chop pruning technique, cutting stems back by one-third in early summer to produce shorter plants with more stable stems at bloom time.

Propagation

To begin, you’ll need seeds, a division of an existing plant, or a potted nursery specimen.

Let’s discuss each method:

From Seed

At the end of the growing season, joe-pye flowers fade and seed pods form. As the pods dry, they split open to reveal fluffy seeds inside.

Collect seeds before the wind disperses them or purchase seeds for fall sowing if needed.

1. Use a garden rake to loosen the top two to three inches of soil in your desired planting area.
2. Lightly water the area, then sprinkle seeds generously over the prepared soil since germination rates tend to be low.
3. Do not cover seeds with soil as they require light to germinate.
4. Water when the top few inches of soil are dry, continuing until the first frost.
5. The following spring, after the last average frost date, resume watering the area when the top few inches of soil are dry.
6. After germination, when the seedlings have two sets of true leaves, thin them to one or two every two to four feet.

Continue watering as needed through the growing season, providing an inch of water per week, including rainfall.

By Division

Dividing mature, overcrowded plants is another effective propagation method.

After seeds disperse in autumn, push a long-handled garden shovel down into the clump to separate a section.

Work the shovel around the division, lifting as you go, until you can lift it freely from the ground.

Prepare the new planting site by working the soil to a depth of 10 to 12 inches until it is crumbly and free from debris.

Set the divided clump at the same depth it was originally growing. The crown, where roots and stems meet, should sit at or slightly above ground level.

Transplanting

To transplant a potted specimen, water it thoroughly the day before.

Prepare the soil as described above, digging to a depth equal to the pot depth and twice as wide.

Remove the plant from its container and set the entire root ball in the ground at the same depth it was in the original container, ensuring the crown sits at or just above the soil surface.

Backfill around the plant, tamp the soil firmly, and water thoroughly. Continue regular watering at approximately one inch per week, including rainfall.

Pests and Disease

When we meet its cultural requirements, E. fistulosum is not prone to pests or disease.

However, in overly dry conditions, you may encounter a few pests.

Flea Beetles

Flea beetles are small pests in the Chrysomelidae family that vary in color, shape, and size.

Adults chew characteristic “shot holes” in leaves and often carry wilting diseases, while larvae feed on roots underground.

Control measures include handpicking adults and dropping them into soapy water, tilling soil around plants to eliminate burrowing grubs, and applying pyrethrin-based insecticides when necessary.

PyGanic Gardening contains pyrethrins, naturally occurring insecticidal compounds derived from daisy flowers.

PyGanic Gardening

Apply it to foliage to target adult beetles and use it as a soil drench to eliminate grubs.

PyGanic Gardening is available from Arbico Organics.

Our guide to managing flea beetles has more information.

Grasshoppers

Young plants are most vulnerable to grasshoppers, medium to large jumping pests of various colors in the Acrididae family that can chew entire plants down to a few ragged stems.

If you can catch them, handpick the pests and drop them into a bucket of soapsuds. Treat plants with a pyrethrin insecticide as above.

Sawflies

Disease

Powdery mildew is a fungal infection that tends to show up during periods of warm temperatures and high humidity.

It appears as a grayish-white powdery coating on the surface of the foliage. Plants grown in part shade conditions tend to be more susceptible.

If there are just a few leaves showing symptoms, you can clip those off and dispose of them in the trash. You can also use neem oil to treat a more substantial infection.

Learn more about powdery mildew here.

Hello, Joe

With full sun, fertile soil, and consistent moisture, hollow joe-pye weed makes a strong vertical statement in the landscape with its tall stems and substantial flower clusters.

As a native species, it adds further value to garden spaces by supporting local wildlife and the ecosystems they inhabit.

Are you ready to welcome hollow joe-pye weed into your landscape? Let us know in the comments section below!

And for more information about growing native flowers in your landscape, add these guides to your reading list next: