Korean rhododendron 'Cornell Pink'
Rhododendron mucronulatum 'Cornell Pink' · Ericaceae
Clear, pure pink flowers cover the bare branches in very early spring, with the forsythias. The leaves turn yellow and bronze in autumn.
- Size
- 6½ ft tall, 5 ft wide
- Zones
- 4 to 7
- Light
- Full sun to part shade
- Flowers
- Late March to mid April
- Pets
- Toxic (severe)
- Job in a bed
- Anchor
A bed built around Korean rhododendron 'Cornell Pink'
The planner designed this bed around Korean rhododendron 'Cornell Pink' 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 Korean rhododendron 'Cornell Pink' stands where it does.
The plants
- 1 Korean rhododendron 'Cornell Pink' × 1, pink
- 2 Leadwort × 38, blue
- 3 Coral bells 'Firefly' × 13, red
- 4 White mugwort × 4, cream
- 5 Astilbe 'Purple Candles' × 3, purple
- 6 Palm sedge × 5, green leaves
- 7 Camassia × 5, white
- 8 Easter lily × 3, white
Why this plant
- The only open bowls. The others are dense clusters, airy sprays, plumes and others. Shape reads at a distance, where colours blur.
- The only pink.
- 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 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 white mugwort (5 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 late March to mid April.
- Opens the season. In all that time nothing else on the plan is in flower.
Planned as an English border: 6 of the 7 groups (86%) are drifts, longer along the bed than they are deep. Coral bells 'Firefly' and leadwort finish the front edge. The most in flower at one time is 3 kinds, from mid July.
The planner's own design check: 11 Excellent, 4 Good, 2 Satisfactory.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where Korean rhododendron 'Cornell Pink' 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.
The first rhododendron to flower. Pink beside the yellow of forsythia is a classic picture of early spring. Plant it where morning sun will not strike frozen flowers.
- The earliest rhododendron
- Partnering with forsythia
- Woodland edges
What to plant with Korean rhododendron 'Cornell Pink'
Plants recorded as good partners for it, and what each pairing does:
- Forsythia: in flower together for four weeks, from late March.
- Daffodil: in flower together for two weeks, from mid April; low enough (16 in) to stand in front of it.
- Siberian squill: in flower together for four weeks, from late March; low enough (5 in) to stand in front of it.
Questions about Korean rhododendron 'Cornell Pink'
Does Korean rhododendron 'Cornell Pink' need sun or shade?
Korean rhododendron 'Cornell Pink' 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 soil that stays evenly moist, rich in organic matter, and a good soak in dry spells.
What zones does Korean rhododendron 'Cornell Pink' grow in?
USDA zones 4 to 7. It is hardy to zone 4, which means it survives winter nights down to about −20 °F (−29 °C).
Above zone 7 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 Korean rhododendron 'Cornell Pink' flower in my zone?
In zone 5 it flowers late March to mid April. As a spring flower it moves about a week for every zone: earlier where it is warmer, later where it is colder.
| Zone 4 | Early April to late April |
|---|---|
| Zone 5 | Late March to mid April |
| Zone 6 | Late March to mid April |
| Zone 7 | Mid March to early 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 Korean rhododendron 'Cornell Pink' be planted?
4½ ft (130 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 6½ ft (200 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many Korean rhododendron 'Cornell Pink' plants do I need?
Usually one. At 4½ ft (130 cm) across, it is a plant you place, not one you mass. For a hedge or screen, set them 4½ ft apart: three plants for a 10 ft run.
In the bed above, the planner used one in one group.
Is Korean rhododendron 'Cornell Pink' poisonous to dogs and cats?
Yes: severe toxicity to people, dogs, cats and horses. All parts, including the nectar, are highly poisonous if eaten and can affect the heart. Even a few leaves can make a pet seriously ill.
Rated from NC State Extension and the ASPCA. Where references disagree, the more cautious rating is used.
Is there a pet-safe plant like Korean rhododendron 'Cornell Pink'?
These come closest to doing what Korean rhododendron 'Cornell Pink' does, and no toxicity is recorded for them:
- Flowering currant: the same job in a bed, the same flowering time and the same colour; 8 in wider, wants average soil.
- Summersweet: the same job in a bed and the same colour; 4 in narrower, flowers mid July to mid August.
- Camellia 'April Blush': the same job in a bed, the same flowering time and the same colour; 20 in shorter, 4 in narrower.
Matched the way the planner's Swap button matches plants: the same job in a bed, then size, then flowering time.
Do deer eat Korean rhododendron 'Cornell Pink'?
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.
What flowers after Korean rhododendron 'Cornell Pink'?
Korean rhododendron 'Cornell Pink' is over by mid April. These start as it finishes and carry the same spot on, so it never goes flat:
- Daffodil: from mid April to early May, 16 in tall, to stand in front of it and cover its fading stems (a recorded partner).
- Reblooming lilac 'Bloomerang': from mid May to early June, 5 ft tall, to stand in front of it and cover its fading stems.
- Bleeding heart: from early May to early June, 2½ ft tall, to stand in front of it and cover its fading stems.
What does Korean rhododendron 'Cornell Pink' look like in winter?
Korean rhododendron 'Cornell Pink' drops its leaves and stands as bare branches. That is when to see its shape, and to prune it if it needs pruning.
Is Korean rhododendron 'Cornell Pink' good for bees and butterflies?
Korean rhododendron 'Cornell Pink' is visited by pollinators and specialist bees.
It is native to the United States and Canada (this is a named variety of the native plant).
More Rhododendron
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In these guides
- Garden plants toxic to cats
- Garden plants toxic to dogs
- Native plants for shade
- Garden plants native to Canada
- Plants for bees
Every fact on record
- Type
- Shrub
- Size
- 6½ ft (200 cm) tall, 5 ft (150 cm) wide
- Plant
- 4½ ft (130 cm) apart
- Height class
- Very tall (5 to 6½ ft)
- Place in the bed
- Back
- Flowers
- Late March to mid April; open bowls; pink
- Leaves
- Medium texture, deciduous; green
- Shape
- Upright, clumping
- Hardy in
- USDA zones 4 to 7
- Light
- Full sun, part sun, part shade
- Soil
- Rich, evenly moist
- Water
- Moderate
- Feeding
- Light, in spring
- Family
- Ericaceae
- Comes from
- Northeastern North America
- Attracts
- Pollinators, specialist bees
Checked against NC State Extension and ASPCA poison lists. 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.