Boneset
Eupatorium perfoliatum · Asteraceae
Flat heads of fuzzy white flowers in late summer on a stout native of wet meadows, whose paired leaves are joined around the stem.
- Size
- 4 ft tall, 3 ft wide
- Zones
- 3 to 8
- Light
- Full sun to part sun
- Flowers
- Early August to mid September
- Pets
- Toxic to people
- Job in a bed
- Drift
A bed built around boneset
The planner designed this bed around boneset when this page was made: a 12 × 6 ft (3.7 × 1.8 m) naturalistic planting in zone 6, full sun. It chose the other plants from the 251 that suit those conditions and its wet soil, and says below why boneset stands where it does.
The plants
- 1 Boneset × 1, white
- 2 Lingonberry × 12, pink
- 3 Mouse-ear coreopsis 'Nana' × 5, yellow
- 4 Turtlehead 'Hot Lips' × 3, pink
- 5 Gray's sedge × 3, green
- 6 Palm sedge × 3, green leaves
- 7 Poet's daffodil × 3, white
- 8 Quamash × 10, blue
Why this plant
- The only flat plates. The others are bells, daisies, spires and others. Shape reads at a distance, where colours blur.
Why here
- Anchors a back corner. At 4 ft it is the tallest plant here, and the tallest close the ends of the bed, where they stand in front of nothing.
- A step in the back row. Next to Gray's sedge (2½ ft): no two neighbours there are the same height, so the back steps up and down like a skyline.
- One plant, alone. A feature plant is seen as an object, and needs clear ground around it.
Why now
- In flower for 7 weeks. From early August to mid September.
- In company. With turtlehead 'Hot Lips' and Gray's sedge in mid August: 3 kinds at once.
Planned as a naturalistic planting: low grasses and groundcovers, the matrix, make up 68% of the planted ground. The most in flower at one time is 5 kinds, in late May. The bed is balanced: the left half carries 51% of the visual weight and the right half 49%.
The planner's own design check: 10 Excellent, 7 Good. It flags one thing to watch: Nothing on this plan is highly poisonous or an aggressive spreader.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where boneset goes in a border
At 4 ft it belongs at the back of a bed. In the planner's ten height classes it is moderately tall (3 to 4 ft).
Its job: drift. Planted in a small group of three or five, and repeated further along in the other number.
The white counterpart to Joe Pye weed, and at home in the same wet ground. Its flat white heads set off the pink domes beside it and draw an extraordinary range of insects.
- Rain gardens and wet soil
- Late nectar for pollinators
- White beside Joe Pye weed
What to plant with boneset
Plants recorded as good partners for it, and what each pairing does:
- Joe Pye weed 'Gateway': in flower together for seven weeks, from early August; bold leaves against its medium ones.
- Swamp milkweed: in flower together for two weeks, from early August.
- New England aster: in flower together for two weeks, from early September.
Questions about boneset
Does boneset need sun or shade?
Boneset grows in full sun (6 or more hours of direct sun a day) and part sun (4 to 6 hours of sun, including some afternoon sun).
It wants moist to wet soil, of average fertility, and plenty of water.
What zones does boneset grow in?
USDA zones 3 to 8. It is hardy to zone 3, which means it survives winter nights down to about −30 °F (−34 °C).
Above zone 8 it struggles: the zones measure winter cold, but a plant's top zone usually means the summers are too hot or the winters too mild for it to rest.
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
When does boneset flower in my zone?
In zone 5 it flowers early August to mid September. As a summer flower it moves about half a week for every zone: earlier where it is warmer.
| Zone 3 | Early August to mid September |
|---|---|
| Zone 4 | Early August to mid September |
| Zone 5 | Early August to mid September |
| Zone 6 | Early August to mid September |
| Zone 7 | Late July to mid September |
| Zone 8 | Late July to mid September |
Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.
How far apart should boneset be planted?
2½ ft (75 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 3 ft (90 cm), so a group knits into one patch.
It grows 4 ft (120 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many boneset plants do I need?
At 2½ ft apart, set out in staggered rows:
- 2 to fill 10 square feet (about 1 m²)
- 5 for a single row 10 ft (3 m) long
- 6 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as a group of three or five, with a second group further along in the other number.
In the bed above, the planner used one in one group.
Is boneset poisonous?
Yes: mild toxicity to people. Can cause vomiting if eaten in quantity.
Rated from NC State Extension. Where references disagree, the more cautious rating is used.
Do deer eat boneset?
Mostly not. NC State lists it as resistant to deer and rabbits. No plant is proof against a hungry deer in a hard winter, but this one is low on the menu.
What flowers after boneset?
Boneset is over by mid September. These start as it finishes and carry the same spot on, so it never goes flat:
- New England aster: from early September to mid October, 4 ft tall (a recorded partner).
- Garden chrysanthemum: from mid September to late October, 24 in tall, to stand in front of it and cover its fading stems.
- Montauk daisy: from mid September to late October, 3 ft tall, to stand in front of it and cover its fading stems.
What does boneset look like in winter?
Boneset dies down, but leave the stems standing: the seed heads stand through the winter, and songbirds eat the seed. Cut them down in early spring, before the new shoots come.
Is boneset good for bees and butterflies?
Boneset is visited by pollinators, bees, butterflies, beneficial insects and songbirds.
It is native to the United States and Canada.
In these guides
- Plants for wet soil and rain gardens
- Deer-resistant perennials for full sun
- Rabbit-resistant plants
- Native perennials for pollinators
- Garden plants native to Canada
- Plants for butterflies
- Plants for bees
- Plants that feed garden birds
- Tall perennials and grasses for the back of a border
- Plants for a white garden
Zone guides: Zone 3 · Zone 4 · Zone 5 · Zone 6 · Zone 7 · Zone 8
Every fact on record
- Type
- Perennial
- Size
- 4 ft (120 cm) tall, 3 ft (90 cm) wide
- Plant
- 2½ ft (75 cm) apart
- Height class
- Moderately tall (3 to 4 ft)
- Place in the bed
- Back
- Flowers
- Early August to mid September; flat plates; white
- Leaves
- Medium texture, herbaceous; green
- Shape
- Upright, clumping
- Hardy in
- USDA zones 3 to 8
- Light
- Full sun, part sun
- Soil
- Average, moist to wet
- Water
- High
- Feeding
- None needed
- Family
- Asteraceae
- Comes from
- Eastern and central USA and Canada
- Attracts
- Pollinators, bees, butterflies, beneficial insects, songbirds
- Stands up to
- Deer, rabbits
Checked against NC State Extension and VASCAN (plants of Canada). Flowering times are for zone 5: later in colder zones, earlier in warmer ones. Toxicity and spread information is a general gardening guide, not veterinary or medical advice, and invasive status varies by region. If a person or pet eats a plant, contact poison control or a vet. Check your local invasive species list before planting anything with a spread warning.