Peony 'Karl Rosenfield'
Paeonia lactiflora 'Karl Rosenfield' · Paeoniaceae Popular
Large, double flowers of bright crimson red on strong stems. The standard red peony since 1908.
- Size
- 3 ft tall, 3 ft wide
- Zones
- 3 to 8
- Light
- Full sun to part sun
- Flowers
- Late May to mid June
- Pets
- Toxic (mild)
- Job in a bed
- Specimen
A bed built around peony 'Karl Rosenfield'
The planner designed this bed around peony 'Karl Rosenfield' 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 peony 'Karl Rosenfield' stands where it does.
The plants
- 1 Peony 'Karl Rosenfield' × 1, red
- 2 Blue fescue 'Elijah Blue' × 8, blue-green leaves
- 3 Leadwort × 21, blue
- 4 Garden phlox 'David' × 3, white
- 5 Japanese aster 'Blue Star' × 5, lavender
- 6 Surprise lily × 12, pink
- 7 Spring starflower × 12, blue
Why this plant
- The only bold leaves here. The rest are fine and medium. A change of leaf keeps plants distinct when nothing is in flower.
- The only open bowls. The others are dense clusters, daisies and trumpets. Shape reads at a distance, where colours blur.
- The only red. The one hot colour: every other flower here is cool or neutral.
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 Japanese aster 'Blue Star' (18 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.
- Fills a gap. For four of those weeks nothing else on the plan is in flower.
Planned as an English border: 5 of the 5 groups (100%) are drifts, longer along the bed than they are deep. There is more leadwort than anything else, 21 plants in all. The scheme leans cool (blue, lavender and pink) and uses red for warmth, with white to calm things between them.
The planner's own design check: 11 Excellent, 6 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 peony 'Karl Rosenfield' 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.
A red that holds in sun and looks rich beside the blue of Siberian irises. The leaves turn bronze-red in autumn, a second season of colour.
- Red for early summer
- Cutting
- Autumn leaf colour
What to plant with peony 'Karl Rosenfield'
Plants recorded as good partners for it, and what each pairing does:
- Siberian iris: in flower together for three weeks, from late May; fine leaves against its bold ones.
- Catmint 'Walker's Low': in flower together for four weeks, from late May; fine leaves against its bold ones; spires rising out of its mound.
- Lady's mantle: red against green, opposite each other on the colour wheel, in flower together for three weeks; medium leaves against its bold ones; low enough (18 in) to stand in front of it.
Questions about peony 'Karl Rosenfield'
Does peony 'Karl Rosenfield' need sun or shade?
Peony 'Karl Rosenfield' 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 peony 'Karl Rosenfield' 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 peony 'Karl Rosenfield' 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 3 | Early June to late June |
|---|---|
| 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 |
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 peony 'Karl Rosenfield' be planted?
2½ ft (80 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 3 ft (85 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many peony 'Karl Rosenfield' plants do I need?
At 2½ ft apart, set out in staggered rows:
- 2 to fill 10 square feet (about 1 m²)
- 4 for a single row 10 ft (3 m) long
- 5 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 peony 'Karl Rosenfield' 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 peony 'Karl Rosenfield'?
Peony 'Karl Rosenfield' 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.
- Yarrow: from mid June to late August, 24 in tall, to stand in front of it and cover its fading stems.
What does peony 'Karl Rosenfield' look like in winter?
Peony 'Karl Rosenfield' 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
- 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 'Sarah Bernhardt' Paeonia lactiflora 'Sarah Bernhardt'
- Tree peony Paeonia suffruticosa
In these guides
Zone guides: Zone 3 · Zone 4 · Zone 5 · Zone 6 · Zone 7 · Zone 8
Every fact on record
- Type
- Perennial
- Size
- 3 ft (85 cm) tall, 3 ft (90 cm) wide
- Plant
- 2½ ft (80 cm) apart
- Height class
- Medium tall (2½ to 3 ft)
- Place in the bed
- Middle
- Flowers
- Late May to mid June; open bowls; red
- Leaves
- Bold texture, herbaceous; dark green
- Shape
- Rounded, clumping
- Hardy in
- USDA zones 3 to 8
- Light
- Full sun, part sun
- Soil
- Rich, well-drained
- Water
- Moderate
- Feeding
- Light, in spring
- Family
- Paeoniaceae
Checked against 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.