Pink evening primrose
Oenothera speciosa · Onagraceae
Silky, cup-shaped flowers of pale pink veined in rose, as wide as a palm, open by day in great numbers in early summer.
- Size
- 16 in tall, 3 ft wide
- Zones
- 4 to 9
- Light
- Full sun
- Flowers
- Late May to late July
- Pets
- No toxicity recorded
- Job in a bed
- Carpet
A bed built around pink evening primrose
The planner designed this bed around pink evening primrose when this page was made: a 12 × 6 ft (3.7 × 1.8 m) naturalistic planting in zone 6, full sun. It chose the other plants from the 715 that suit those conditions and its dry soil, and says below why pink evening primrose stands where it does.
The plants
- 1 Pink evening primrose × 3, pink
- 2 Blue moor grass × 5, purple
- 3 Heath aster 'Snow Flurry' × 4, white
- 4 False sunflower 'Summer Sun' × 3, yellow
- 5 Brown-eyed Susan × 3, yellow
- 6 Dwarf English boxwood × 1, dark green leaves
- 7 Star of Persia × 5, purple
- 8 Daffodil 'February Gold' × 12, yellow
Why this plant
- Part of the matrix. The low fabric of grasses and groundcovers that the taller plants come up through.
- The only open bowls. The others are spires, daisies, globes and others. Shape reads at a distance, where colours blur.
- The only pink.
Why here
- Under the taller plants. It runs back between them as living mulch: there its job is to cover the soil, not to be looked at.
- 3 plants in one group. Massed, one kind reads as a single shape. Scattered, it would look spotty.
Why now
- In flower for 10 weeks. From late May to late July.
- Fills a gap. For one of those weeks nothing else on the plan is in flower.
Planned as a naturalistic planting: low grasses and groundcovers, the matrix, make up 60% of the planted ground. Cool colours (pink and purple) set against hot ones (yellow), with white to calm things between them. Brown-eyed Susan and false sunflower 'Summer Sun' anchor the back corners of the bed: the tallest plants on the plan stand there.
The planner's own design check: 8 Excellent, 7 Good, 2 Satisfactory. It flags one thing to watch: Pink evening primrose spreads aggressively. Each plant's details say more.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where pink evening primrose goes in a border
At 16 in it belongs at the front of a bed. In the planner's ten height classes it is short (12 to 18 in).
Its job: carpet. A groundcover planted in threes and fives to cover the soil: along the front, and just behind it.
Beautiful and a thug: it runs underground through everything. Use it on a dry bank or a roadside strip, where it has no neighbours to swamp.
- Dry banks and roadside strips
- Hot, poor soil
- Confined beds
What to plant with pink evening primrose
Plants recorded as good partners for it, and what each pairing does:
- Little bluestem: its blue-green leaves are a setting for the flowers, before and after; tall enough (3 ft) to stand behind it; happy in the same dry soil.
- Adam's needle: in flower together for four weeks, from late June; bold leaves against its medium ones; spires rising out of its mound.
- Russian sage: in flower together for three weeks, from mid July; spires rising out of its mound; tall enough (4 ft) to stand behind it.
Questions about pink evening primrose
Does pink evening primrose need sun or shade?
Pink evening primrose grows in full sun (6 or more hours of direct sun a day).
It wants dry, sharply drained soil, on the lean side, with no feeding, and little watering once settled.
What zones does pink evening primrose 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 pink evening primrose flower in my zone?
In zone 5 it flowers late May to late July. 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 early August |
|---|---|
| Zone 5 | Late May to late July |
| Zone 6 | Mid May to late July |
| Zone 7 | Early May to mid July |
| Zone 8 | Early May to mid July |
| Zone 9 | Late April to mid July |
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 pink evening primrose be planted?
24 in (60 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 16 in (40 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many pink evening primrose plants do I need?
At 24 in apart, set out in staggered rows:
- 3 to fill 10 square feet (about 1 m²)
- 6 for a single row 10 ft (3 m) long
- 10 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as threes and fives, along the front and just behind it.
In the bed above, the planner used three in one group.
Is pink evening primrose 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.
Do deer eat pink evening primrose?
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.
Will pink evening primrose spread?
It spreads sideways, by runners or roots; the risk of it taking over is high. Spreads aggressively by underground runners and by seed, and is very hard to remove. Plant it only where it is confined.
What flowers after pink evening primrose?
Pink evening primrose is over by late July. These start as it finishes and carry the same spot on, so it never goes flat:
- Lilyturf: from early August to mid September, 16 in tall.
- Ornamental onion 'Millenium': from mid July to late August, 18 in tall.
- Black-eyed Susan 'American Gold Rush': from mid July to early October, 24 in tall.
What does pink evening primrose look like in winter?
Pink evening primrose 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.
Is pink evening primrose good for bees and butterflies?
Pink evening primrose is visited by pollinators, specialist bees and butterflies.
It is native to the United States.
More Oenothera
- Gaura 'Siskiyou Pink' Oenothera lindheimeri 'Siskiyou Pink'
- Gaura 'Whirling Butterflies' Oenothera lindheimeri 'Whirling Butterflies'
- Missouri evening primrose Oenothera macrocarpa
- Sundrops Oenothera fruticosa
- Sundrops 'Fireworks' Oenothera fruticosa 'Fyrverkeri'
In these guides
- Pet-safe plants for a sunny border
- Native perennials for pollinators
- Plants for butterflies
- Plants for bees
- Groundcover plants
Zone guides: Zone 4 · Zone 5 · Zone 6 · Zone 7 · Zone 8 · Zone 9
Every fact on record
- Type
- Perennial (groundcover)
- Size
- 16 in (40 cm) tall, 3 ft (90 cm) wide
- Plant
- 24 in (60 cm) apart
- Height class
- Short (12 to 18 in)
- Place in the bed
- Front
- Flowers
- Late May to late July; open bowls; pink, white
- Leaves
- Medium texture, herbaceous; green
- Shape
- Mat-forming, spreading
- Hardy in
- USDA zones 4 to 9
- Light
- Full sun
- Soil
- Lean, dry and sharply drained
- Water
- Low
- Feeding
- None needed
- Family
- Onagraceae
- Comes from
- Nebraska, Kansas, Missouri, Oklahoma, Texas, Mexico
- Attracts
- Pollinators, specialist bees, butterflies
- Stands up to
- Poor soil
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.