How to Grow Brodiaea Plants in your Garden

Gardener's HQ Guide to Growing Grassnut and Clusterlily

Brodiaea is a hardy bulb. Plants grow to between 30 and 90 cm (1 to 3 feet) in height.

There ares many different species in the genus, and commonly grown polants include Clusterlily, Grassnut, Blue-dicks, Firecracker flower, and Ithuriel's spear.

Brodiaea elegans
Brodiaea elegans (Elegant Cluster-lily) by Tom Hilton.

Brodiaea flowers in the spring with star shaped white or violet blooms.

Commonly Grown Brodiaea Species

Brodiaea filifolia

Brodiaea filifolia
Brodiaea filifolia (Threadleaf Brodiaea), photograph by USFWS Pacific Southwest Region; CC.

Brodiaea coronaria

Brodiaea coronaria syn. Brodiaea grandiflora.

Brodiaea coronaria
Brodiaea coronaria (Harvest Brodiaea / Crown Brodiaea), picture by A.Davey; CC.

Brodiaea Growing and Care Guide

Common Names: Clusterlily, Brodiaea, Grassnut, Fire-cracker flower, Blue-dicks, Ithuriel’s spear.
Family: Asparagaceae.
Life Cycle: Hardy bulb.
Height: 12 to 36 inches (30 to 90 cm).
Native: Americas.

Growing Region: Zones 6 to 10.
Flowers: Spring through to early summer.
Flower Details: White, purple, violet. Tube. Star-shaped.
Foliage: Herbaceous. A few basal leaves.

Sow Outside:
Seed: 1/8 inch (3 mm). Autumn. Bulb: 3 to 4 inches (7 to 10 cm). Beginning of Autumn. Spacing 3 to 6 inches (7 to 15 cm).
Sow Inside: Seeds should be sown in vermiculite and watered from below.  Germination time: one to three months. Temperature 55 to 60°F (13 to 16°C). Sow in the spring, transplant outdoors in autumn.

Requirements: Full sunlight. Good drainage. Gritty soil, loose soil. With the exception of Brodiaea peduncularis which requires a heavy soil. Regular watering during the growing season; cease watering once flowering has finished. It will take two years for seed grown plants to flower, so easier to grow from bulbs. Propagate: cormels can be planted in the autumn.

I hope that you enjoyed this guide on how to grow Brodiaea. You may also enjoy the following growing guides: How to grow Asparagus in the garden and the Common aspidistra plant.

How to Grow Brodiaea

If planning to grow Brodiaea outdoors, then seeds should be planted in the autumn. Sow seeds at a depth of 3 mm (1/8th inch). Ideally bulbs should be planted in early autumn, at a depth of 10 cm (4 inches).

When growing Brodiaea members indoors first, then it is best to sow and germinate them at a temperature of around 15 degrees Celsius (59°F).

They typically take from one to three months to germinate.

It is important to water plants from below, as their leaves tend to be sensitive to water and can decay.

The seedlings of grassnut and related Brodiaea species should then be planted out in the autumn. It will take about two years until plants bear flowers.

Ideally, Brodiaea plants should be located in a sunny area of the garden at about 10 cm (4 inches) apart. It is important to use a gritty soil that has excellent drainage.

Brodiaea douglasii
Brodiaea douglasii (Douglas' Brodiaea) by Plinkk.

Caring for Brodiaea in the Garden

Brodiaea may require to be watered during dry spells, but do not water at other times of the year.

In very damp or very hot summers, Grassnut bulbs should be moved indoors. Replant outside again in the Autumn.

Common Questions

How many members does the Brodiaea genus have?

The Brodiaea genus includes around 15 species.

Do members of Brodiaea make a good garden or landscaping plant?

Yes, Brodiaea are appreciated in gardens for their attractive, brightly colored flowers.

Which Brodiaea species are most frequently grown by gardeners?

Brodiaea 'Queen Fabiola' is often grown for its deep blue, star-shaped flowers.

Are members of the Brodiaea plant genus fragrant?

No, Brodiaea plants are not known for their fragrance, but they are loved for their vibrant blooms.

What is the perfect location to grow Brodiaea?

Brodiaea prefers full sun to partial shade and well-drained soil.

Is Brodiaea invasive in the USA?

Currently, Brodiaea is not considered invasive in the USA.

How do I remove Brodiaea plants from my garden?

To remove Brodiaea, dig out the bulbs, making sure to remove the entire bulb to prevent regrowth.


Brodiaea is a genus in the Asparagaceae family, native to western North America. These bulbous perennials are known for their star-shaped flowers that bloom in late spring to early summer, adding a splash of color to the garden.

Plant Brodiaea bulbs in the fall in a sunny or partly shaded location with well-drained soil. They are drought-tolerant once established, but need watering during the growing season. Despite their delicate appearance, they're quite hardy and can survive in various climates.

I hope that you enjoyed this guide on how to grow Brodiaea plants. You may also enjoy the following Gardener's HQ Asparagaceae family growing guides: How to grow Aspidistra elatior; Yucca thompsoniana, Mondo Grass, and Muscari plants.