Common camas

Common camas: how do you recognise it?

Habit

Slender bulb with a few narrow leaves and a straight flower stem of 30–50 cm.

Leaves

Narrow, linear and grass-like, fresh green; they die back in June.

Flower

Loose spikes of starry flowers 3–4 cm across with six narrow petals, in May.

Colour

Deep blue to violet, sometimes paler blue; the anthers are yellow.

Bulb

Egg-shaped bulb with a brown tunic, which forms offsets.

Flowering: May · Plants: September–November

Why grow it?

• Deep blue flower spikes in May, a colour that always stands out in the garden.
• One of the few bulbs that does well in moist, heavy soil.
• Naturalises in grass and after a few years forms a small blue meadow.
• Bees and bumblebees collect nectar and pollen from it.
• Fully hardy and easy: it comes back every year.

Common camas: where does it grow best?

• Sun to partial shade; it flowers most freely in full sun.
• Loam, clay or humus-rich peaty soil; acid, neutral or chalky.
• Moist to wet: the soil may be damp in spring, even in a boggy meadow.
• Plant 10–15 cm apart, in large groups or scattered through grass.

Light

Sun and partial shade

Soil type

Loam, clay or peat

Acidity

Not fussy

Moisture

Normal or wet

Size

0.5 m tall, 0.15 m wide

Hardiness

Hardy (to -25 °C)

Goes well with

• Snake’s head fritillary: Flowers just before the camas in the same moist soil.
• Siberian iris: Narrow leaves and blue or purple flowers at the pond edge.
• Daffodil: Also naturalises in grass and brings colour in April.
• Cuckooflower: Small lilac flowers in a damp wildflower meadow.
• Meadowsweet: Takes over in summer in a wet border.

Common camas: when and how to plant it?

Plant in September–November.

1. Plant in September–November, while the ground is not frozen.
2. Dig one hole per group or, in grass, lift a piece of turf and replace it after planting.
3. Set the bulbs 10 cm deep, pointed end up.
4. Keep 10–15 cm between bulbs; in grass, scatter them and plant where they fall for a natural look.
5. Firm the soil and water if the ground is dry.
6. In a border, mix some compost into the soil.

Care

Watering

Not normally needed. In a dry spring, water until flowering is over.

Feeding

In a border, a layer of compost in spring; in grass, do not feed.

Mowing

Only mow the grass at the end of June, once the leaves have yellowed and the seed is ripe.

Foliage

Let the leaves die back naturally after flowering: this is how the bulb builds up strength.

Spent flowers

Leave them if you want it to self-seed; otherwise cut them off in June.

Tip: Plant it in large groups in orchard grass or by a pond and do not mow until the end of June: it will then self-seed and the patch of blue gets bigger every year.

Common camas: when to prune it?

When: Common camas is not pruned. At most you cut off the faded stems in June.

How:

• Cut faded stems just above ground level in June, or leave them for seed.
• Clear the leaves once they are fully yellow.
• In grass: only mow at the end of June and do not set the mower too low.

Caution: Do not mow or cut too early: if the leaves are still green, it will flower less next year.

Pruning calendar and basic rules

Propagation

Offsets

Lift a crowded clump in July–August, once the leaves have died back, separate the bulbs and replant them in autumn.

Seed

In grass it self-seeds. You can also sow ripe seed in summer or autumn in a pot left outdoors; seedlings take a few years to flower.

Common camas: how does it get through the winter?

Hardy to −25 °C.

• Fully hardy, to about −25 °C: in Belgium it stays in the ground without protection.
• Wet winters are no problem, as long as water does not stand on the surface.
• In a pot: stand the pot against a wall so the bulbs do not freeze solid.

Diseases and pests

• Slugs: They eat the young leaves and flower buds. Pick them off in the evening.
• Mown too early: After a few years there are fewer flowers in the grass. Only mow at the end of June, when the leaves are yellow.
• Few flowers: Too much shade or clumps too crowded. Lift, divide and replant in a lighter spot.
• Yellow leaves after flowering: This is normal: the bulb is going dormant. Let the leaves die back naturally.

Through the year

• March: Leaves appear. Give compost in the border.
• April: Flower buds appear. Watch for slugs.
• May: In flower: deep blue spikes. Plenty of bees.
• June: Leaves yellow and seed ripens. Mow at the end of the month.
• July: Dormant. Lift and divide crowded clumps.
• September: Plant bulbs 10 cm deep.
• October: Plant bulbs in borders or grass.
• November: Plant the last bulbs.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Did you know?

• For the Indigenous peoples of north-western North America the bulb was an important food. They cooked it for hours in pit ovens, which made it sweet.
• The names Camassia and quamash come from the Indigenous name for the plant, camas in English.
• In 1805 the Lewis and Clark expedition was given dried camas bulbs by the Nez Perce, when the explorers came out of the mountains half-starved.