For a fun addition to containers and gardens, look no further than fiber optic grass. Though technically not a grass (it’s in the closely related sedge family), this unique plant forms a spreading, grasslike clump of thin, cylindrical stems. The stems grow upright at first, then arch gracefully, creating a rounded fountain shape. Small silvery white flower heads develop on each stem tip, making the plant look a bit like a bundle of fiber optic light strands. Fiber optic grass is ideal for tall containers or hanging baskets where its stems can cascade freely.
Common name: Fiber optic grass, low bulrush
Botanical name: Isolepis cernua
Plant type: Annual or short-lived perennial
Zones: 8 to 11 as a perennial; all zones as an annual
Height: 6 to 10 inches
- Sun: Full sun or partial shade
- Soil: Moisure-retentive loam, clay, or potting mix (in containers)
- Moisture: Needs constant moisture
- Mulch: None
- Pruning: Cut back in late winter
- Fertilizer: Apply diluted soluble fertilizer as needed
Pests and diseases
- No serious problems
- ‘Live Wire’ is essentially the same as the species.
- Fiber optic grass loves moisture, making it a great choice for bog gardens or the edge of ponds and water gardens.
- Fiber optic grass can be overwintered indoors as a houseplant if provided with bright light and cool temperatures.
- Fiber optic grass provides a great head of “hair” when planted in novelty face pots.
All in the family
- Fiber optic grass is a member of the sedge family (Cyperaceae), a large group containing over 5,000 species of grasslike plants.
- The largest genus in the family is Carex, which includes many moisture-loving ornamentals.
- Most sedge family plants have triangular stems, though oval-stemmed fiber optic grass is one of the exceptions.