Use & Care NotesCompanion Plants
Lucerne Blue-Eyed Grass: Little Blue Stars Along the Path
Save
Lucerne blue-eyed grass looks like a small ornamental grass until it blooms. Then the tuft of stiff, dark green, sword-like leaves is sprinkled with bright purplish-blue, six-petaled stars, each with a small golden eye. Despite the name, it is not a grass at all but a member of the iris family, and Lucerne has larger flowers than typical blue-eyed grass, about three-quarters of an inch across.
Lucerne at a glance
| Trait | What to expect |
|---|---|
| Botanical name | Sisyrinchium 'Lucerne' |
| Flowers | Purplish-blue stars with a yellow eye, about 3/4 inch |
| Foliage | Narrow, stiff, dark green, fan-shaped tuft |
| Size | About 10 inches tall, 15 inches wide |
| Bloom | Late May, peak early June, repeat flowers through summer |
| Hardiness | USDA zones 5 to 8 |
| Light | Full sun to part shade |
| Deer | Susceptible |
Near the lavender, not in it
Blue-eyed grass grows naturally in moist meadows and open woods, so it wants soil that drains but never dries out for long. Lavender wants the opposite. The happy compromise is a path edge or border front next to your lavender bed, where the hose or sprinkler reaches regularly and the soil stays a bit richer.
From there it does a lot for the planting. Its blue stars open in late May, before most lavender, so it gives the area color early. Its stiff, spiky leaves echo the upright feel of lavender stems at a smaller scale. Sketch where the watered edge falls in the Companion Plant Planner.
Planting and care
- Soil: average, well drained but steadily moist. Waterlogged soil can cause root rot.
- Water: regular water in summer. In hot, dry sites the leaves can brown and the plant may go semi-dormant.
- After bloom: each flower lasts a day, but new ones keep coming. Shear after the main flush to tidy and encourage more.
- Dividing: split clumps in spring every few years to keep them vigorous.
- Winter: hardy in Michigan within its zone range. Good drainage prevents winter crown rot.
Small spaces, big charm
At about 10 inches tall, Lucerne suits rock gardens, containers, rain garden edges and the front of a border. It is noted for not self-seeding aggressively, so it stays where you put it. Pollinators visit the small flowers, and the neat tufts look tidy even out of bloom.
Frequently asked questions
Is it really related to iris?
Yes. Blue-eyed grass belongs to the iris family; the flattened stems and fan of sword-like leaves give it away.
Can I cut the flowers?
Not really. They are tiny and last only a day. Enjoy them in the garden.
Plug tray or bare root?
The 72-cell plug tray is best for edging long paths or for growers. The bare root plant suits a single spot at home. See each product page for current availability.
Share how it went in your field