Tree peony
Paeonia suffruticosa ·
A woody shrub that does not die back, with enormous, silky flowers up to 25 cm across in late spring, and handsome, deeply cut, grey-green leaves.
- Size
- 5 ft tall, 5 ft wide
- Zones
- 4 to 8
- Light
- Full sun to part shade
- Flowers
- Early May to late May
- Pets
- Toxic (mild)
- Job in a bed
- Specimen
A bed built around tree peony
The planner designed this bed around tree peony when this page was made: a 16 × 8 ft (4.9 × 2.4 m) English border in zone 6, part sun. It chose the other plants from the 708 that suit those conditions, and says below why tree peony stands where it does.
The plants
- 1 Tree peony × 1, pink
- 2 Carpathian bellflower × 12, blue
- 3 Leadwort × 24, blue
- 4 Bee balm 'Jacob Cline' × 4, red
- 5 Foxglove beardtongue × 3, white
- 6 Palm sedge × 5, green leaves
- 7 Eastern bee balm × 3, pink
- 8 Easter lily × 4, white
- 9 Camassia × 4, blue
- 10 Red spider lily × 8, red
Why this plant
- The only bold leaves here. The rest are medium and fine. A change of leaf keeps plants distinct when nothing is in flower.
- The only open bowls. The others are bells, dense clusters, globes and others. Shape reads at a distance, where colours blur.
- Part of the bed's structure. Shrubs and grasses keep their shape when the perennials die down. So does palm sedge.
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 bee balm 'Jacob Cline' (4 ft): no two neighbours there are the same height, so the back steps up and down like a skyline.
- One plant, alone. A shrub is seen as an object, and needs clear ground around it.
Why now
- In flower for four weeks. From early May to late May.
- Part of the bed's peak. With foxglove beardtongue, eastern bee balm and camassia in late May: 4 kinds at once. No week has more.
Planned as an English border: 9 of the 9 groups (100%) are drifts, longer along the bed than they are deep. The bed is balanced: the left half carries 51% of the visual weight and the right half 49%. Leadwort is planted in six places along the bed, which gives it rhythm.
The planner's own design check: 12 Excellent, 5 Good.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where tree peony 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: specimen. A feature plant with a shape of its own. It stands alone with room around it, and repeats only at a distance.
The most opulent flower in the garden, on a plant that can outlive its owner. Shelter it from wind and hot afternoon sun, plant it deep, and never cut it to the ground.
- A treasured specimen
- Late-spring flowers in part shade
- Long-lived, low-maintenance planting
What to plant with tree peony
Plants recorded as good partners for it, and what each pairing does:
- Siberian iris: fine leaves against its bold ones; low enough (2½ ft) to stand in front of it.
- Lady's mantle: medium leaves against its bold ones; low enough (18 in) to stand in front of it.
- Cranesbill 'Rozanne': takes over when it finishes, flowering from early June; medium leaves against its bold ones; low enough (18 in) to stand in front of it.
Questions about tree peony
Does tree peony need sun or shade?
Tree peony grows in full sun (6 or more hours of direct sun a day), part sun (4 to 6 hours of sun, including some afternoon sun) and part shade (2 to 4 hours of sun, mostly in the morning).
It wants ordinary well-drained soil, rich in organic matter, and a good soak in dry spells.
What zones does tree peony grow in?
USDA zones 4 to 8. It is hardy to zone 4, which means it survives winter nights down to about −20 °F (−29 °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 tree peony flower in my zone?
In zone 5 it flowers early May to late May. As a spring flower it moves about a week for every zone: earlier where it is warmer, later where it is colder.
| Zone 4 | Mid May to early June |
|---|---|
| Zone 5 | Early May to late May |
| Zone 6 | Early May to late May |
| Zone 7 | Late April to mid May |
| Zone 8 | Mid April to early May |
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 tree peony be planted?
4 ft (120 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 5 ft (150 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 tree peony plants do I need?
Usually one. At 4 ft (120 cm) across, it is a plant you place, not one you mass. For a hedge or screen, set them 4 ft apart: three plants for a 10 ft run.
In the bed above, the planner used one in one group.
Is tree peony poisonous to dogs and cats?
Yes: mild toxicity to dogs, cats and horses. Can cause vomiting and diarrhoea in pets if eaten.
Rated from NC State Extension. Where references disagree, the more cautious rating is used.
Is there a pet-safe plant like tree peony?
These come closest to doing what tree peony does, and no toxicity is recorded for them:
- Black chokeberry: the same size and the same flowering time; an anchor, not a specimen, white, not pink.
- Dappled willow: the same job in a bed; 12 in taller, 12 in wider.
- Joe Pye weed 'Gateway': the same job in a bed and the same colour; 12 in taller, 12 in narrower.
Matched the way the planner's Swap button matches plants: the same job in a bed, then size, then flowering time.
What flowers after tree peony?
Tree peony is over by late May. These start as it finishes and carry the same spot on, so it never goes flat:
- Siberian iris: from late May to late June, 2½ ft tall, to stand in front of it and cover its fading stems (a recorded partner).
- Lady's mantle: from late May to early July, 18 in tall, to stand in front of it and cover its fading stems (a recorded partner).
- Cranesbill 'Rozanne': from early June to early October, 18 in tall, to stand in front of it and cover its fading stems (a recorded partner).
What does tree peony look like in winter?
Tree peony drops its leaves and stands as bare branches. That is when to see its shape, and to prune it if it needs pruning.
More Paeonia
- Fernleaf peony Paeonia tenuifolia
- Itoh peony 'Bartzella' Paeonia 'Bartzella'
- Peony Paeonia lactiflora
- Peony 'Bowl of Beauty' Paeonia lactiflora 'Bowl of Beauty'
- Peony 'Coral Charm' Paeonia 'Coral Charm'
- Peony 'Festiva Maxima' Paeonia lactiflora 'Festiva Maxima'
- Peony 'Karl Rosenfield' Paeonia lactiflora 'Karl Rosenfield'
- Peony 'Sarah Bernhardt' Paeonia lactiflora 'Sarah Bernhardt'
In these guides
Zone guides: Zone 4 · Zone 5 · Zone 6 · Zone 7 · Zone 8
In flower in: May
Every fact on record
- Type
- Shrub
- Size
- 5 ft (150 cm) tall, 5 ft (150 cm) wide
- Plant
- 4 ft (120 cm) apart
- Height class
- Tall (4 to 5 ft)
- Place in the bed
- Back
- Flowers
- Early May to late May; open bowls; pink, red, white, purple, yellow
- Leaves
- Bold texture, deciduous; green
- Shape
- Rounded, clumping
- Hardy in
- USDA zones 4 to 8
- Light
- Full sun, part sun, part shade
- Soil
- Rich, well-drained
- Water
- Moderate
- Feeding
- Light, in spring
Checked against NC State Extension. 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.