Canadian burnet
Sanguisorba canadensis · Rosaceae
Tall stems of upright, fluffy, white bottlebrushes in early autumn, over handsome, ladder-like leaves.
- Size
- 5 ft tall, 2½ ft wide
- Zones
- 3 to 8
- Light
- Full sun to part sun
- Flowers
- Mid August to early October
- Pets
- No toxicity recorded
- Job in a bed
- Drift
A bed built around canadian burnet
The planner designed this bed around canadian burnet when this page was made: a 12 × 6 ft (3.7 × 1.8 m) cottage garden 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 canadian burnet stands where it does.
The plants
- 1 Canadian burnet × 3, white
- 2 Lingonberry × 6, pink
- 3 Mouse-ear coreopsis 'Nana' × 17, yellow
- 4 Garden phlox 'Jeana' × 3, pink
- 5 Inkberry 'Gem Box' × 1, dark green leaves
- 6 Checkered lily × 12, purple
Why this plant
- The only spires. The others are bells, daisies and dense clusters. Shape reads at a distance, where colours blur.
- The only white. White sits between stronger colours and calms them.
Why here
- Anchors a back corner. At 5 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 inkberry 'Gem Box' (2½ ft): no two neighbours there are the same height, so the back steps up and down like a skyline.
- 3 plants in one group. Massed, one kind reads as a single shape. Scattered, it would look spotty.
Why now
- In flower for 8 weeks. From mid August to early October.
- Closes the season. For its last two weeks nothing else on the plan is in flower.
Planned as a cottage garden: 21 of the 30 plants (70%), bulbs aside, stand alone or in groups of no more than five, small enough for the kinds to mingle. The back corners are held by garden phlox 'Jeana' and canadian burnet, the tallest plants on the plan. Something is in flower for 22 weeks between mid April and early October, with a pause of 3 weeks from late June.
The planner's own design check: 9 Excellent, 6 Good, 2 Satisfactory. 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 canadian burnet goes in a border
At 5 ft it belongs at the back of a bed. In the planner's ten height classes it is tall (4 to 5 ft).
Its job: drift. Planted in a small group of three or five, and repeated further along in the other number.
A native of wet meadows that flowers when the season is nearly over. White spires at this height are rare in September. It needs moisture and stands without staking.
- White spires for early autumn
- Rain gardens and wet meadows
- Native planting
What to plant with canadian burnet
Plants recorded as good partners for it, and what each pairing does:
- New England aster: in flower together for five weeks, from early September.
- Joe Pye weed 'Gateway': in flower together for five weeks, from mid August; bold leaves against its medium ones.
- New York ironweed: in flower together for six weeks, from mid August.
Questions about canadian burnet
Does canadian burnet need sun or shade?
Canadian burnet 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, rich in organic matter, and plenty of water.
What zones does canadian burnet 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 canadian burnet flower in my zone?
In zone 5 it flowers mid August to early October. As a summer flower it moves about half a week for every zone: earlier where it is warmer.
| Zone 3 | Late August to early October |
|---|---|
| Zone 4 | Late August to early October |
| Zone 5 | Mid August to early October |
| Zone 6 | Mid August to early October |
| Zone 7 | Early August to early October |
| Zone 8 | Early August to early October |
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 canadian burnet be planted?
24 in (60 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 2½ ft (75 cm), so a group knits into one patch.
It grows 5 ft (150 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many canadian burnet plants do I need?
At 24 in apart, set out in staggered rows:
- 3 to fill 10 square feet (about 1 m²)
- 6 for a single row 10 ft (3 m) long
- 10 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 three in one group.
Is canadian burnet poisonous to dogs and cats?
No toxicity is recorded for dogs, cats, horses or people, according to NC State Extension.
"Not toxic" is not "edible": a pet that eats a lot of any plant can be sick.
Do deer eat canadian burnet?
They may. NC State does not list it as resistant to deer or rabbits. Where they visit, protect it, or plant it among ones they avoid.
Will canadian burnet spread?
It spreads sideways, by runners or roots; the risk of it taking over is moderate. Spreads slowly by rhizomes into wide clumps in wet soil.
What flowers after canadian burnet?
Canadian burnet is over by early October. These start as it finishes and carry the same spot on, so it never goes flat:
- Tatarian aster 'Jindai': from early October to early November, 4 ft tall.
- Chrysanthemum 'Sheffield Pink': from late September to early November, 2½ ft tall, to stand in front of it and cover its fading stems.
- Swamp sunflower: from late September to late October, 6½ ft tall.
What does canadian burnet look like in winter?
Canadian burnet dies down to the ground and there is nothing to see until spring. The old stems can be cut in autumn, or left until spring as shelter for overwintering insects.
More Sanguisorba
- Burnet 'Tanna' Sanguisorba officinalis 'Tanna'
- Great burnet Sanguisorba officinalis
- Japanese burnet Sanguisorba obtusa
In these guides
- Plants for wet soil and rain gardens
- Pet-safe plants for a sunny border
- Garden plants native to Canada
- Tall perennials and grasses for the back of a border
- Plants with spires: vertical accents
- Plants that flower in fall
- 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
- 5 ft (150 cm) tall, 2½ ft (75 cm) wide
- Plant
- 24 in (60 cm) apart
- Height class
- Tall (4 to 5 ft)
- Place in the bed
- Back
- Flowers
- Mid August to early October; upright spires; white
- Leaves
- Medium texture, herbaceous; green
- Shape
- Upright, spreading
- Hardy in
- USDA zones 3 to 8
- Light
- Full sun, part sun
- Soil
- Rich, moist to wet
- Water
- High
- Feeding
- None needed
- Family
- Rosaceae
- Comes from
- North America
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.