Feather Reed Grass
Calamagrostis × acutiflora
Strictly upright and self-supporting, which is rare in a grass this tall — provided you keep it sunny and leave it unfed.
- Type
- Grass · Perennial
- Botanical family
- Mixed / other
- Foliage color
- Green · Gold and chartreuse
- Sunlight
- Full sun to partial shade.
- Watering
- Little needed once established.
- Feeding
- None required.
- Frost tolerant
- Yes
- Flowering
- June
- Pruning
- Cut to 10 cm in late February.
- Overwintering
- Hardy enough to leave standing through winter, unprotected.
- Mar–Jun Spring Growth
- Jun–Sep Flowering
- Sep–Dec Growing
- Dec–Dec Leaf Fall
- Jan–Mar Leaf Fall
- Plant spacing
- 23.6 in
- In-row spacing
- 23.6 in
- Between rows
- 2 ft 6 in
- Square-foot density
- Not suited to SFG
- Root system
- A dense fibrous mat
- Working depth
- 8–24 in
- Can reach
- 5 ft down where the soil allows
- Spread
- 24 in–4 ft across, about 1–2× the width of the plant
- Shallowest pot
- 12 in of soil
Thousands of fine roots knit the top of the soil into a turf, which is what holds a bank together and what makes an established clump so hard to lift. Prairie grasses send a few roots far below the mat as well.
The habit is Feather Reed Grass’s own; the figures are what that habit usually comes to at this size, not a measurement of this species. Roots follow the soil either way: a compacted pan, a high water table or heavy clay stops them well short of any of it, and deep open ground lets them go further.
- Rust Rust, now and then, through a humid summer.
- Center die-back in older clumps — divide to bring it back.
Grasses, like this one.
The Cottage Garden Companion — the gardener's herbarium at cottagegardencompanion.com