Double Japanese kerria
Kerria japonica 'Pleniflora' · Rosaceae
Upright, bright green canes carry golden-yellow pompoms, like small chrysanthemums, in spring and on and off through summer.
- Size
- 6½ ft tall, 6½ ft wide
- Zones
- 4 to 9
- Light
- Part sun to shade
- Flowers
- Mid April to mid May
- Pets
- No toxicity recorded
- Job in a bed
- Anchor
A bed built around double Japanese kerria
The planner designed this bed around double Japanese kerria when this page was made: a 16 × 8 ft (4.9 × 2.4 m) English border in zone 6, part shade. It chose the other plants from the 513 that suit those conditions, and says below why double Japanese kerria stands where it does.
The plants
- 1 Double Japanese kerria × 1, yellow
- 2 Woodland strawberry × 11, white
- 3 Leadwort × 11, blue
- 4 Tall astilbe 'Superba' × 3, purple
- 5 Astilbe 'Purple Candles' × 3, purple
- 6 Lenten rose × 8, pink
- 7 Bigleaf aster × 4, lavender
- 8 Canada lily × 3, orange
- 9 Double snowdrop × 12, white
- 10 Hardy cyclamen × 7, pink
Why this plant
- The bed's only structure. Shrubs and grasses keep their shape when the perennials die down, and it is the only one here.
- The only globes. The others are open bowls, dense clusters, plumes and others. Shape reads at a distance, where colours blur.
- A classic partner for Lenten rose. Both are on this plan. A pairing gardeners have proved outranks a general rule.
Why here
- Anchors a back corner. At 6½ 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 tall astilbe 'Superba' (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 five weeks. From mid April to mid May.
- In company. With woodland strawberry and Lenten rose in early May: 3 kinds at once.
Planned as an English border: 10 of the 11 groups (91%) are drifts, longer along the bed than they are deep. The bed is balanced: the left half carries 47% of the visual weight and the right half 53%. Woodland strawberry is planted in three places along the bed, which gives it rhythm.
The planner's own design check: 11 Excellent, 5 Good, 1 Satisfactory.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where double Japanese kerria goes in a border
At 6½ ft it belongs at the back of a bed. In the planner's ten height classes it is very tall (5 to 6½ ft).
Its job: anchor. A shrub that gives the bed permanent structure. Planted singly, as soon as the front edge is laid; everything else is arranged around it.
It flowers in real shade, and its green stems are a winter feature. It suckers into a thicket and looks best when the oldest canes are cut out each year.
- Flowers in shade
- Green winter stems
- Informal screens
What to plant with double Japanese kerria
Plants recorded as good partners for it, and what each pairing does:
- Hosta: its green leaves are a setting for the flowers, before and after; bold leaves against its medium ones; low enough (18 in) to stand in front of it.
- Lenten rose: purple against yellow, opposite each other on the colour wheel, if you choose those colours, in flower together for four weeks; bold leaves against its medium ones; low enough (18 in) to stand in front of it.
- Christmas fern: its dark green leaves are a setting for the flowers, before and after; low enough (20 in) to stand in front of it.
Questions about double Japanese kerria
Does double Japanese kerria need sun or shade?
Double Japanese kerria grows in part sun (4 to 6 hours of sun, including some afternoon sun), part shade (2 to 4 hours of sun, mostly in the morning) and shade (less than 2 hours of direct sun, or bright dappled light).
It wants ordinary well-drained soil, of average fertility, and a good soak in dry spells. Once settled in, it stands drought.
What zones does double Japanese kerria 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 double Japanese kerria flower in my zone?
In zone 5 it flowers mid April to mid 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 | Late April to late May |
|---|---|
| Zone 5 | Mid April to mid May |
| Zone 6 | Mid April to early May |
| Zone 7 | Early April to early May |
| Zone 8 | Late March to late April |
| Zone 9 | Late March to mid April |
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 double Japanese kerria be planted?
5 ft (150 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 6½ ft (200 cm), so a group knits into one patch.
It grows 6½ ft (200 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many double Japanese kerria plants do I need?
Usually one. At 5 ft (150 cm) across, it is a plant you place, not one you mass. For a hedge or screen, set them 5 ft apart: three plants for a 10 ft run.
In the bed above, the planner used one in one group.
Is double Japanese kerria 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.
Is there a native plant like double Japanese kerria?
Double Japanese kerria comes from Central & Southern China to Southern Korea and Japan. These North American natives come closest to doing its job:
- Pinxterbloom azalea: the same job in a bed and the same flowering time; 8 in narrower, pink, not yellow.
- Large fothergilla: the same job in a bed and the same flowering time; 20 in taller, 12 in wider.
- Siberian dogwood: the same job in a bed and the same size; flowers late May to early June, white, not yellow.
Matched the way the planner's Swap button matches plants: the same job in a bed, then size, then flowering time.
Do deer eat double Japanese kerria?
Mostly not. NC State lists it as resistant to deer. No plant is proof against a hungry deer in a hard winter, but this one is low on the menu.
Will double Japanese kerria spread?
It spreads sideways, by runners or roots; the risk of it taking over is moderate. Spreads by suckers into a wide thicket. Remove unwanted canes at the base.
What flowers after double Japanese kerria?
Double Japanese kerria is over by mid May. These start as it finishes and carry the same spot on, so it never goes flat:
- Blue false indigo: from late May to mid June, 4 ft tall, to stand in front of it and cover its fading stems.
- Foxglove: from early June to mid July, 4 ft tall, to stand in front of it and cover its fading stems.
- Northern Lights azalea: from mid May to early June, 5 ft tall, to stand in front of it and cover its fading stems.
What does double Japanese kerria look like in winter?
Double Japanese kerria drops its leaves and stands as bare branches: it is grown for green winter stems. That is when to see its shape, and to prune it if it needs pruning.
Is double Japanese kerria good for bees and butterflies?
Double Japanese kerria is visited by butterflies and hummingbirds.
More Kerria
- Japanese kerria Kerria japonica
In these guides
- Plants for dry shade
- Deer-resistant plants for shade
- Pet-safe plants for shade
- Plants for hummingbirds
- Plants for butterflies
Zone guides: Zone 4 · Zone 5 · Zone 6 · Zone 7 · Zone 8 · Zone 9
Every fact on record
- Type
- Shrub
- Size
- 6½ ft (200 cm) tall, 6½ ft (200 cm) wide
- Plant
- 5 ft (150 cm) apart
- Height class
- Very tall (5 to 6½ ft)
- Place in the bed
- Back
- Flowers
- Mid April to mid May; globes; yellow
- Leaves
- Medium texture, deciduous; green
- Shape
- Upright, spreading
- Hardy in
- USDA zones 4 to 9
- Light
- Part sun, part shade, shade
- Soil
- Average, well-drained
- Water
- Moderate
- Feeding
- None needed
- Family
- Rosaceae
- Comes from
- Central & Southern China to Southern Korea and Japan
- Attracts
- Butterflies, hummingbirds
- Stands up to
- Deer, drought
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.