Quamash
Camassia quamash ·
Spikes of starry, deep blue flowers above grassy leaves in late spring. A native of western meadows that are wet in spring and dry in summer.
- Size
- 18 in tall, 6 in wide
- Zones
- 4 to 8
- Light
- Full sun to part sun
- Flowers
- Early May to late May
- Pets
- Not checked
- Job in a bed
- Bulb layer
A bed built around quamash
The planner designed this bed around quamash 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 quamash stands where it does.
The plants
- 1 Dianthus 'Kahori' × 3, pink
- 2 Leadwort × 15, blue
- 3 Foxglove beardtongue × 3, white
- 4 Tatarian aster 'Jindai' × 4, purple
- 5 Globe arborvitae 'Danica' × 1, green leaves
- 6 Caucasian scabious 'Fama' × 3, blue
- 7 Quamash × 8, blue
- 8 Schubert's allium × 2, pink
Why this plant
- Nothing here is unique to it. Its leaf, flower shape and colour are all on the plan already. Its case rests on where it stands and when it performs.
Why here
- In the middle. At 18 in it stands ahead of foxglove beardtongue (3½ ft) without hiding it.
- 8 plants in 2 handfuls. In the gaps between other plants, which fill the space when the bulb is not in growth.
Why now
- In flower for four weeks. From early May to late May.
- Opens the season. In its first week nothing else on the plan is in flower.
- Leaves gone by midsummer. They die back and leave bare ground. A perennial that comes up late stands beside it, and grows over the gap.
Planned as an English border: 5 of the 6 groups (83%) are drifts, longer along the bed than they are deep. Blue is the colour seen most, on 3 of the 7 kinds grown for their flowers. The bed is tied together by its repeats: two kinds come round again along it, leadwort and Tatarian aster 'Jindai'.
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 quamash goes in a border
At 18 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: bulb layer. Small bulbs planted in handfuls of five or seven in the gaps between other plants, for colour before the perennials wake up.
Shorter and more intensely blue than the large camassia. It is one of the few bulbs that thrive in heavy, moist soil, and it looks best in drifts through grass.
- Naturalising in damp grass
- Rain gardens
- Bridging tulips and early summer
What to plant with quamash
Plants recorded as good partners for it, and what each pairing does:
- Golden Alexanders: blue against yellow, opposite each other on the colour wheel, in flower together for four weeks; grows up in time to hide its dying leaves; happy in the same moist soil.
- Siberian iris: grows up in time to hide its dying leaves; tall enough (2½ ft) to stand behind it; happy in the same moist soil.
- Wild geranium: in flower together for four weeks, from early May; grows up in time to hide its dying leaves; a low mound at the foot of its spires.
Questions about quamash
Does quamash need sun or shade?
Quamash 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 soil that stays evenly moist, of average fertility, and a good soak in dry spells.
What zones does quamash grow in?
USDA zones 4 to 8. It is hardy to zone 4, which means it survives winter nights down to about −20 °F (−29 °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 quamash flower in my zone?
In zone 5 it flowers early May to late 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 | Mid May to early June |
|---|---|
| Zone 5 | Early May to late May |
| Zone 6 | Early May to late May |
| Zone 7 | Late April to mid May |
| Zone 8 | Mid April to early May |
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 quamash be planted?
4 in (10 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 6 in (15 cm), so a group knits into one patch.
It grows 18 in (45 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many quamash plants do I need?
At 4 in apart, set out in staggered rows:
- 107 to fill 10 square feet (about 1 m²)
- 31 for a single row 10 ft (3 m) long
- 343 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as handfuls of five or seven, in the gaps between other plants.
In the bed above, the planner used eight in two groups.
What can I plant to hide quamash's leaves after it flowers?
A bulb's leaves have to be left to yellow for about six weeks after flowering, to feed next year's flowers. Plant it among perennials that come up late and spread wide, and they grow over the leaves as they fade:
- Wild geranium: 20 in tall and 18 in wide, a recorded partner, in flower early May to late May.
- Lady's mantle: 18 in tall and 24 in wide, in flower late May to early July.
- Catmint 'Walker's Low': 24 in tall and 2½ ft wide, in flower mid May to mid September.
What does quamash look like in winter?
Quamash is underground: it dies back after flowering and waits as a bulb until spring. Mark where it is, so a fork does not find it first.
More Camassia
- Camassia Camassia leichtlinii
In these guides
Zone guides: Zone 4 · Zone 5 · Zone 6 · Zone 7 · Zone 8
In flower in: May
Every fact on record
- Type
- Bulb
- Size
- 18 in (45 cm) tall, 6 in (15 cm) wide
- Plant
- 4 in (10 cm) apart
- Height class
- Short (12 to 18 in)
- Place in the bed
- Front
- Flowers
- Early May to late May; upright spires; blue
- Leaves
- Fine texture, summer-dormant; green
- Shape
- Upright, clumping
- Hardy in
- USDA zones 4 to 8
- Light
- Full sun, part sun
- Soil
- Average, evenly moist
- Water
- Moderate
- Feeding
- None needed
Not yet checked against an outside reference: its figures rest on general horticultural knowledge. 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.