Itoh peony 'Bartzella'
Paeonia 'Bartzella' · Popular
A cross between tree and garden peonies: huge, scented, lemon-yellow flowers with a red flare, as many as fifty on a mature plant, on strong stems that need no staking.
- Size
- 3 ft tall, 3½ ft wide
- Zones
- 4 to 9
- Light
- Full sun to part sun
- Flowers
- Late May to mid June
- Pets
- Toxic (mild)
- Job in a bed
- Specimen
A bed built around Itoh peony 'Bartzella'
The planner designed this bed around Itoh peony 'Bartzella' when this page was made: a 12 × 6 ft (3.7 × 1.8 m) English border in zone 6, full sun. It chose the other plants from the 966 that suit those conditions, and says below why Itoh peony 'Bartzella' stands where it does.
The plants
- 1 Itoh peony 'Bartzella' × 1, yellow
- 2 Winter heath × 8, pink
- 3 Blanket flower 'Arizona Sun' × 5, red
- 4 Swamp milkweed 'Ice Ballet' × 3, white
- 5 Slender mountain mint × 3, white
- 6 Chives × 8, purple
- 7 Star of Persia × 4, purple
- 8 Hyacinth × 7, blue
Why this plant
- The only open bowls. The others are bells, daisies, flat plates and others. Shape reads at a distance, where colours blur.
- The only yellow.
Why here
- Anchors a back corner. At 3 ft it is one of the taller plants 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 star of Persia (20 in): 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 four weeks. From late May to mid June.
- Part of the bed's peak. With blanket flower 'Arizona Sun', chives and star of Persia in mid June: 4 kinds at once. No week has more.
Planned as an English border: 6 of the 6 groups (100%) are drifts, longer along the bed than they are deep. Something is in flower for 36 weeks, from late January to early October. The flowering is at its height in mid June, with 4 kinds out together.
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 Itoh peony 'Bartzella' goes in a border
At 3 ft it belongs in the middle of a bed. In the planner's ten height classes it is medium tall (2½ to 3 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.
It has the flowers of a tree peony on a plant that dies back like a garden peony, and the foliage stays good until autumn. Yellow is rare in peonies; pair it with blue iris and catmint.
- A yellow peony
- A long-lived specimen for the border
- Handsome foliage after flowering
What to plant with Itoh peony 'Bartzella'
Plants recorded as good partners for it, and what each pairing does:
- Siberian iris: purple against yellow, opposite each other on the colour wheel, if you choose those colours, in flower together for three weeks.
- Catmint 'Walker's Low': in flower together for four weeks, from late May; spires rising out of its mound.
- Salvia 'May Night': purple against yellow, opposite each other on the colour wheel, in flower together for three weeks; spires rising out of its mound.
Choosing between it and a look-alike? Peony vs Itoh peony 'Bartzella'.
Questions about Itoh peony 'Bartzella'
Does Itoh peony 'Bartzella' need sun or shade?
Itoh peony 'Bartzella' 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 ordinary well-drained soil, rich in organic matter, and a good soak in dry spells.
What zones does Itoh peony 'Bartzella' grow in?
USDA zones 4 to 9. It is hardy to zone 4, which means it survives winter nights down to about −20 °F (−29 °C).
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
When does Itoh peony 'Bartzella' flower in my zone?
In zone 5 it flowers late May to mid June. As a spring flower it moves about a week for every zone: earlier where it is warmer, later where it is colder.
| Zone 4 | Late May to late June |
|---|---|
| Zone 5 | Late May to mid June |
| Zone 6 | Mid May to mid June |
| Zone 7 | Early May to early June |
| Zone 8 | Early May to early June |
| Zone 9 | Late April to late 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 Itoh peony 'Bartzella' be planted?
3 ft (90 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 3½ ft (100 cm), so a group knits into one patch.
It grows 3 ft (90 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many Itoh peony 'Bartzella' plants do I need?
At 3 ft apart, set out in staggered rows:
- 1 to fill 10 square feet (about 1 m²)
- 4 for a single row 10 ft (3 m) long
- 4 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as one, with clear ground around it: a feature plant is seen as an object, and a group of them is a thicket.
In the bed above, the planner used one in one group.
Is Itoh peony 'Bartzella' poisonous to dogs and cats?
Yes: mild toxicity to dogs, cats and horses. Can cause vomiting and diarrhoea in pets if eaten.
What flowers after Itoh peony 'Bartzella'?
Itoh peony 'Bartzella' is over by mid June. These start as it finishes and carry the same spot on, so it never goes flat:
- Black-eyed Susan: from mid July to mid September, 24 in tall, to stand in front of it and cover its fading stems.
- Butterfly weed: from late June to early August, 24 in tall, to stand in front of it and cover its fading stems.
- Daylily: from late June to early August, 2½ ft tall.
What does Itoh peony 'Bartzella' look like in winter?
Itoh peony 'Bartzella' 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 Paeonia
- Fernleaf peony Paeonia tenuifolia
- 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'
- Tree peony Paeonia suffruticosa
In these guides
Zone guides: Zone 4 · Zone 5 · Zone 6 · Zone 7 · Zone 8 · Zone 9
Every fact on record
- Type
- Perennial
- Size
- 3 ft (90 cm) tall, 3½ ft (100 cm) wide
- Plant
- 3 ft (90 cm) apart
- Height class
- Medium tall (2½ to 3 ft)
- Place in the bed
- Middle
- Flowers
- Late May to mid June; open bowls; yellow
- Leaves
- Medium texture, herbaceous; dark green
- Shape
- Mounding, clumping
- Hardy in
- USDA zones 4 to 9
- Light
- Full sun, part sun
- Soil
- Rich, well-drained
- Water
- Moderate
- Feeding
- Light, in spring
Not yet checked against an outside reference: its figures rest on general horticultural knowledge. 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.