Cowslip
Primula veris · Primulaceae
Nodding clusters of small, scented, deep yellow bells, each in a pale, inflated calyx, on stalks above a rosette of crinkled leaves.
- Size
- 10 in tall, 10 in wide
- Zones
- 3 to 8
- Light
- Full sun to part shade
- Flowers
- Mid April to mid May
- Pets
- Toxic (mild)
- Job in a bed
- Drift
A bed built around cowslip
The planner designed this bed around cowslip when this page was made: a 12 × 6 ft (3.7 × 1.8 m) cottage garden in zone 6, part sun. It chose the other plants from the 708 that suit those conditions, and says below why cowslip stands where it does.
The plants
- 1 Cowslip × 13, yellow
- 2 Bloody cranesbill × 5, pink
- 3 Swamp milkweed 'Ice Ballet' × 3, white
- 4 Bee balm 'Purple Rooster' × 3, purple
- 5 Inkberry 'Gem Box' × 1, dark green leaves
- 6 Japanese aster 'Blue Star' × 3, lavender
- 7 Hyacinth 'Delft Blue' × 5, blue
- 8 Red spider lily × 7, red
Why this plant
- The only bells. The others are open bowls, flat plates, globes and others. Shape reads at a distance, where colours blur.
- The only yellow.
Why here
- Near the front. At 10 in it stands ahead of inkberry 'Gem Box' (2½ ft) without hiding it.
- 13 plants in 3 groups (5, 5 and 3). Seen again further along, the same plant ties the bed together.
Why now
- In flower for six weeks. From mid April to mid May.
- Fills a gap. For two of those weeks nothing else on the plan is in flower.
Planned as a cottage garden: 28 of the 28 plants (100%), bulbs aside, stand alone or in groups of no more than five, small enough for the kinds to mingle. Something is in flower for 26 weeks, from mid April to early October. Cowslip is planted in three places along the bed, which gives it rhythm.
The planner's own design check: 13 Excellent, 4 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 cowslip goes in a border
At 10 in it belongs at the front of a bed. In the planner's ten height classes it is low (6 to 12 in).
Its job: drift. Planted in a small group of three or five, and repeated further along in the other number.
The wild cowslip of English meadows. It takes more sun and drier soil than other primroses and will naturalise in thin grass that is mown after midsummer.
- Naturalising in grass
- Spring meadows and orchards
- Cottage gardens
What to plant with cowslip
Plants recorded as good partners for it, and what each pairing does:
- Grape hyacinth: blue against yellow, opposite each other on the colour wheel, in flower together for four weeks; spires rising out of its mound; low enough (6 in) to stand in front of it.
- Checkered lily: purple against yellow, opposite each other on the colour wheel, if you choose those colours, in flower together for four weeks; happy in the same moist soil.
- Lady's mantle: takes over when it finishes, flowering from late May; tall enough (18 in) to stand behind it; happy in the same moist soil.
Questions about cowslip
Does cowslip need sun or shade?
Cowslip 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, of average fertility, and a good soak in dry spells.
What zones does cowslip 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 cowslip 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 3 | Late April to late May |
|---|---|
| Zone 4 | Mid April to late May |
| Zone 5 | Mid April to mid May |
| Zone 6 | Early April to early May |
| Zone 7 | Late March to early May |
| Zone 8 | Late March to late 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 cowslip be planted?
8 in (20 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 10 in (25 cm), so a group knits into one patch.
It grows 10 in (25 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many cowslip plants do I need?
At 8 in apart, set out in staggered rows:
- 27 to fill 10 square feet (about 1 m²)
- 16 for a single row 10 ft (3 m) long
- 86 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as a group of three or five, with a second group further along in the other number.
In the bed above, the planner used 13 in three groups.
Is cowslip poisonous to dogs and cats?
Yes: mild toxicity to dogs, cats and horses. Can cause mild vomiting in pets if eaten.
Rated from NC State Extension and the ASPCA. Where references disagree, the more cautious rating is used.
Is there a pet-safe plant like cowslip?
These come closest to doing what cowslip does, and no toxicity is recorded for them:
- Horned violet: the same colour; an edging, not a drift, 4 in shorter.
- Shooting star: the same job in a bed; 6 in taller, flowers early May to late May.
- Woodland phlox: the same job in a bed and the same flowering time; 4 in wider, blue, lavender or 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 cowslip?
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 cowslip?
Cowslip is over by mid May. These start as it finishes and carry the same spot on, so it never goes flat:
- Lady's mantle: from late May to early July, 18 in tall (a recorded partner).
- Sweet woodruff: from early May to early June, 8 in tall.
- Creeping thyme: from early June to mid July, 3 in tall, to stand in front of it and cover its fading stems.
What does cowslip look like in winter?
Cowslip holds some of its leaves into winter, more in a mild year or a sheltered spot, and they look tired by March. Cut the old ones off as new growth starts.
More Primula
- Drumstick primrose Primula denticulata
- English primrose Primula vulgaris
- Japanese primrose Primula japonica
- Orchid primrose Primula vialii
- Polyanthus primrose Primula x polyantha
- Siebold's primrose Primula sieboldii
In these guides
Zone guides: Zone 3 · Zone 4 · Zone 5 · Zone 6 · Zone 7 · Zone 8
Every fact on record
- Type
- Perennial
- Size
- 10 in (25 cm) tall, 10 in (25 cm) wide
- Plant
- 8 in (20 cm) apart
- Height class
- Low (6 to 12 in)
- Place in the bed
- Front
- Flowers
- Mid April to mid May; hanging bells; yellow
- Leaves
- Medium texture, semi-evergreen; green
- Shape
- Mounding, self-seeding
- Hardy in
- USDA zones 3 to 8
- Light
- Full sun, part sun, part shade
- Soil
- Average, evenly moist
- Water
- Moderate
- Feeding
- None needed
- Family
- Primulaceae
- Comes from
- Europe and Algeria
- Stands up to
- Heat, humidity
Checked against NC State Extension, ASPCA poison lists 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.