Blue Oat Grass (Helictotrichon sempervirens) | Silver-Blue Fountain Grass

Blue Oat Grass

1 Gallon

$16.90

$16.90 $0.00

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Blue Oat Grass

Helictotrichon sempervirens

A classic evergreen grass with striking metallic silver-blue foliage and a tidy fountain form, perfect for borders and containers.

$16.90

$16.90 $0.00

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Bay Area–Based Nursery

We specialize in plants grown and delivered in their original pots and soil.
Because of their size and weight, our plants are not suitable for long-distance shipping and are delivered locally to ensure health and quality.

While delivery is limited to our local service area, we’re happy to support garden design and plant selection remotely.

For local plant professionals, we’re always glad to connect and explore ways to support your customers.

Helictotrichon sempervirens, commonly known as Blue Oat Grass, is a classic, evergreen ornamental grass prized for its striking, metallic blue-gray foliage and tidy, fountain-like form. This cool-season, clump-forming perennial grows in a dense, perfectly rounded mound of narrow, spiky, upright to slightly arching leaves that maintain their intense silver-blue color throughout the growing season. In late spring to early summer, it produces tall, slender, elegant oat-like flower spikes rising above the foliage, opening greenish-blue and maturing to soft golden-buff, adding airy height and movement. Exceptionally drought-tolerant once established, cold hardy, and adaptable to a range of well-drained soils, it is an outstanding choice for borders, rock gardens, mass plantings, containers, and as a striking accent in water-wise and Mediterranean landscapes.

Knowing how we measure the size?

When browsing our plants, you may notice size terms such as Gallon, Multi, or Stand. These describe how a plant is grown, containerized, or structured at the time of sale — not just its height. Understanding these terms will help you choose the right plant for your space and expectations.

🌱 Gallon Size (Container Size)

Gallon refers to the size of the nursery container the plant is currently growing in (e.g. 1 Gallon, 5 Gallon, 15 Gallon).

A larger gallon size generally means:
- A more established root system
- A sturdier plant
- Faster visual impact after planting
Example:
- 5 Gallon: Ideal for residential gardens, easy to handle, good balance of value and maturity
- 15 Gallon: More mature, provides quicker results in the landscape

Note: Gallon size does not guarantee a specific height, as growth varies by species.

🌳 Multi (Multi-Trunk / Multi-Branch Form)

Multi indicates the plant has multiple trunks or main stems growing from the base.

Commonly used for:
- Ornamental trees
- Feature plants
- Japanese maples, olives, crepe myrtles, etc.
Why choose Multi:
- Fuller, more sculptural appearance
- Strong visual presence even at younger ages
- Popular for design-focused landscapes

🌲 Stand (Single-Trunk / Standard Form)

Stand (short for Standard) refers to a single, dominant trunk with a raised or naturally formed canopy.

Commonly used for:
- Shade trees
- Street trees
- Orchard and structural plantings
Why choose Stand:
- Clean, classic tree form
- Easier clearance for walkways and lawns
- Preferred for long-term structure and uniformity

🌿 Choosing the Right Size

If you want instant impact → larger Gallon, Multi form
If you want long-term structure → Stand form
If you want flexibility and value → mid-size Gallon containers

If you’re unsure which size or form fits your project, our team is happy to help you select the best option based on your space, timeline, and design goals.

Foliage & Flowers: Dense, tidy, rounded fountain mound of narrow, spiky, upright to slightly arching, intensely silver-blue to blue-gray leaves; tall, slender, elegant oat-like flower spikes in late spring to early summer (greenish-blue aging to golden-buff) .
Mature Height: 24-36 inches (2-3 ft)
Mature Spread: 24-36 inches (2-3 ft)
Growth Rate: Slow to moderate
Hardiness Zones: USDA 4-9
Light Requirement: Full sun (essential for best blue color)
Core Benefits: Striking metallic silver-blue foliage, tidy compact fountain form, elegant oat-like flower spikes, drought tolerant, cold hardy, evergreen.
Best Uses: Borders, rock gardens, mass plantings, containers, xeriscape gardens, Mediterranean gardens, coastal gardens, accent specimens.

Q: How large does Blue Oat Grass get?
A: It forms a dense, tidy fountain mound, typically reaching 2-3 feet in both height and spread.

Q: How much sun does it need for the best blue color?
A: For the most intense silver-blue foliage, plant in full sun (at least 6 hours of direct sunlight daily). In partial shade, the foliage will fade to a duller green-blue.

Q: Is it drought tolerant?
A: Yes, once established, it is drought tolerant. Water regularly during its first year, then little to no supplemental water is needed. It thrives in well-drained soils.

Q: Is it evergreen?
A: Yes, it is evergreen in mild winter climates, retaining its striking blue-gray foliage year-round. In colder zones, it may be semi-evergreen.

Q: When does it bloom?
A: It blooms in late spring to early summer, producing tall, elegant oat-like flower spikes that rise above the foliage.

Q: How should I prune it?
A: In late winter or early spring, rake through the clump to remove dead or winter-damaged foliage. Avoid cutting back hard, as this can damage the plant. If needed, divide clumps in early spring every 3-4 years.