Giant Feather Grass, Stipa gigantea
Shimmering, statuesque Stipa gigantea (or Celtica gigantea, although few use this official name) is amongst the most impressive ornamental grasses to grow. Commonly known as giant feather grass or golden oats, it’s one one of the few grasses that gives year-round interest, with a basal clump of evergreen narrow leaves followed by a halo of flower spikes that emerge in early summer before the metallic inflorescences appear a few weeks later. Over the following months those tall flower heads become increasingly golden, swaying beautifully in the breeze to show-stopping effect as they catch the sun. And on most sites those stems will remain standing through winter, looking magical when frost covers the garden, too.
Here’s everything you need to know about growing this standout plant.
Photography by Clare Coulson.
Given the right conditions, Stipa gigantea requires almost no maintenance. It prefers a sunny open position in free-draining soil, so give it plenty of space. The basal foliage alone can sometimes cover a few square feet so don’t crowd it closely to other perennials or shrubs, and consider the height of the spikes as well as the overall height of the plant which can reach up to seven feet tall and as much across. Stipa ‘Goldilocks’ is a slightly more compact cultivar growing to five to six feet tall.
Stipa gigantea makes a great feature plant either as a single specimen or dotted through a border. It is especially suited to gravel gardens on open ground where it can bask in hot conditions. If choosing partners, consider the flower stems which can easily tangle with tall perennials. It’s best underplanted with shorter perennials or grasses, clipped forms, or swathes of bulbs. Or euphorbias which can be deadheaded into neat mounds just as the Stipa begins to flower. In high summer it makes a fantastic backdrop to richly colored perennials, including shorter dahlias or summer bulbs.
- Hardy in USDA Zones 5-10.
- Big, dramatic, and architectural, this is the perfect grass for big spaces and sunny aspects.
- Pair it with shorter grasses, perennials, and bulbs that will not get tangled in the Stipa’s arching stems.
- Because the stems are so light they aren’t too affected by wind, but if you want the stems to last, a slightly sheltered area is best.
Keep It Alive
- In early spring any remaining flower spikes can be completely removed. If the foliage has become messy tidy it up by removing any brown leaves and clip back to a neat mound, but avoid cutting back completely, which can be the kiss of death for the plant.
- Stipa gigantea is happiest in free draining soil and does not require mulching or watering after its first year.
- It will self-seed, although not very prolifically, and any new plants can be moved to a different position if necessary when young.
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Frequently asked questions
What is giant feather grass?
Giant feather grass, also known as Stipa gigantea, is a tall ornamental grass native to southern Europe and parts of Asia. It is prized for its large, feathery plumes that emerge in summer and add a dramatic touch to gardens.
How tall does giant feather grass grow?
Giant feather grass has a height range of 4 to 6 feet (1.2 to 1.8 meters). With its tall and elegant appearance, it serves as an excellent focal point in any garden or landscape.
What are the growing conditions for giant feather grass?
Giant feather grass thrives in well-draining soil and prefers full sun. It is drought-tolerant and can withstand a variety of climates. It is best suited for USDA hardiness zones 5 to 9.
How do I plant giant feather grass?
To plant giant feather grass, start by selecting a sunny location with well-drained soil. Dig a hole that is slightly larger than the root ball of the plant. Place the plant in the hole and backfill with soil, gently firming it around the roots. Water thoroughly after planting and regularly until the plant becomes established.
How often should I water giant feather grass?
Once the giant feather grass is established, it is relatively drought-tolerant and doesn't require frequent watering. However, during hot and dry periods, providing a deep watering every 2-3 weeks is beneficial.
How do I maintain giant feather grass?
Giant feather grass is a low-maintenance plant. In late winter or early spring, trim back the previous year's foliage to a few inches above the ground. This helps rejuvenate the plant and encourages new growth. Additionally, removing any dead or damaged leaves throughout the year will keep the plant looking tidy.
Does giant feather grass spread or become invasive?
Giant feather grass is not known to be invasive. It forms neat clumps and doesn't spread aggressively. However, its seeds can self-sow and produce new plants nearby if conditions are suitable.
Can giant feather grass be grown in containers?
Yes, giant feather grass can be grown in containers. Choose a large container with drainage holes and fill it with a well-draining potting mix. Place the grass in the container and ensure it receives ample sunlight. Water regularly but do not overwater, as the grass is sensitive to waterlogged conditions.
When does giant feather grass bloom?
Giant feather grass typically blooms in late spring to early summer. It produces tall stems with feathery silver plumes that sway gracefully in the breeze, adding visual interest and movement to the garden.
Are there any pests or diseases that affect giant feather grass?
Giant feather grass is generally pest and disease resistant. However, it can occasionally be susceptible to rust or leaf spot diseases. Regular inspection and prompt treatment with appropriate fungicides, if needed, can help control these issues.