Feather reed grass 'Overdam'
Calamagrostis x acutiflora 'Overdam' · Poaceae
A variegated form of feather reed grass: leaves edged with cream, pink-flushed in spring, with the same narrow, upright plumes. It prefers cool summers.
- Size
- 4 ft tall, 18 in wide
- Zones
- 4 to 8
- Light
- Full sun to part sun
- Flowers
- Late June to mid September
- Pets
- No toxicity recorded
- Job in a bed
- Accent
A bed built around feather reed grass 'Overdam'
The planner designed this bed around feather reed grass 'Overdam' when this page was made: a 12 × 6 ft (3.7 × 1.8 m) contemporary bed in zone 6, full sun. It chose the other plants from the 966 that suit those conditions, and says below why feather reed grass 'Overdam' stands where it does.
The plants
- 1 Feather reed grass 'Overdam' × 2, tan
- 2 Mouse-ear coreopsis 'Nana' × 8, yellow
- 3 Creeping phlox 'Emerald Blue' × 5, blue
- 4 Siberian iris 'Caesar's Brother' × 3, purple
- 5 Arborvitae 'Mr. Bowling Ball' × 1, grey-green leaves
- 6 Wild quinine × 5, white
- 7 Hyacinth × 10, pink
Why this plant
- The only plumes. The others are daisies, open bowls, flat plates and others. Shape reads at a distance, where colours blur.
- The only tan. Tan sits between stronger colours and calms them.
- Part of the bed's structure. Shrubs and grasses keep their shape when the perennials die down. So does arborvitae 'Mr. Bowling Ball'.
Why here
- Forward of its height. At 4 ft it is taller than wild quinine (3½ ft) behind it, but airy enough to see through.
- 2 plants in 2 places. An accent is a punctuation mark: the repeat along the bed gives it rhythm.
- Fine leaf against bold. Wild quinine is beside it: the strongest contrast of leaf there is.
Why now
- In flower for 14 weeks. From late June to mid September.
- Closes the season. For its last four weeks nothing else on the plan is in flower.
- Stands through winter. Left uncut, it holds its shape until March, when the perennials have gone.
Planned as a contemporary bed: 31 of the 31 plants that stand in groups (100%) are set out in a pattern with their neighbours: a straight row, a triangle, or five like the five on a dice. Neither end outweighs the other: the visual weight is split 40 to 60, left to right. The bold leaves of wild quinine are set against the fine leaves of feather reed grass 'Overdam', the kind of contrast that keeps a bed from blurring.
The planner's own design check: 12 Excellent, 4 Good, 1 Satisfactory. It flags one thing to watch: Nothing on this plan is highly poisonous or an aggressive spreader.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where feather reed grass 'Overdam' goes in a border
At 4 ft it belongs at the back of a bed. In the planner's ten height classes it is moderately tall (3 to 4 ft). It is airy enough to see through, so it can also come forward and veil what is behind it.
Its job: accent. An upright plant used singly, like a punctuation mark, and repeated at intervals to give the bed rhythm.
Shorter and paler than 'Karl Foerster', it gives the same vertical line with a softer effect. The variegation fades in hot, humid summers.
- A lighter vertical accent
- Brightening a border
- Cool-summer gardens
What to plant with feather reed grass 'Overdam'
Plants recorded as good partners for it, and what each pairing does:
- Cranesbill 'Rozanne': in flower together for 14 weeks, from late June; low enough (18 in) to stand in front of it.
- Salvia 'May Night': in flower together for four weeks, from late June; low enough (24 in) to stand in front of it.
- Purple coneflower: in flower together for 11 weeks, from late June.
Questions about feather reed grass 'Overdam'
Does feather reed grass 'Overdam' need sun or shade?
Feather reed grass 'Overdam' grows in full sun (6 or more hours of direct sun a day) and part sun (4 to 6 hours of sun, including some afternoon sun).
It wants soil that stays evenly moist, of average fertility, and a good soak in dry spells.
What zones does feather reed grass 'Overdam' grow in?
USDA zones 4 to 8. It is hardy to zone 4, which means it survives winter nights down to about −20 °F (−29 °C).
Above zone 8 it struggles: the zones measure winter cold, but a plant's top zone usually means the summers are too hot or the winters too mild for it to rest.
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
When does feather reed grass 'Overdam' flower in my zone?
In zone 5 it flowers late June to mid September. As a summer flower it moves about half a week for every zone: earlier where it is warmer.
| Zone 4 | Late June to mid September |
|---|---|
| Zone 5 | Late June to mid September |
| Zone 6 | Late June to mid September |
| Zone 7 | Mid June to mid September |
| Zone 8 | Mid June to mid September |
Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.
How far apart should feather reed grass 'Overdam' be planted?
18 in (45 cm) apart, from the middle of one plant to the middle of the next. That is about its full width, so each plant keeps its own outline.
It grows 4 ft (120 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many feather reed grass 'Overdam' plants do I need?
At 18 in apart, set out in staggered rows:
- 5 to fill 10 square feet (about 1 m²)
- 7 for a single row 10 ft (3 m) long
- 17 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as one at a time, repeated along the bed at intervals; a slender one reads better as a clump of three.
In the bed above, the planner used two in two groups.
Is feather reed grass 'Overdam' poisonous to dogs and cats?
No toxicity is recorded for dogs, cats, horses or people, according to NC State Extension.
"Not toxic" is not "edible": a pet that eats a lot of any plant can be sick.
Is there a native plant like feather reed grass 'Overdam'?
Feather reed grass 'Overdam' is not native to North America. These North American natives come closest to doing its job:
- Little bluestem 'Standing Ovation': the same job in a bed and the same colour; 8 in shorter, flowers early August to mid September.
- Blue vervain: the same job in a bed and the same size; flowers mid July to early September, blue, not tan.
- Rattlesnake master: the same job in a bed and the same size; flowers mid July to late August, white, not tan.
Matched the way the planner's Swap button matches plants: the same job in a bed, then size, then flowering time.
What flowers after feather reed grass 'Overdam'?
Feather reed grass 'Overdam' is over by mid September. These start as it finishes and carry the same spot on, so it never goes flat:
- Garden chrysanthemum: from mid September to late October, 24 in tall, to stand in front of it and cover its fading stems.
- Blue wood aster: from mid September to mid October, 3 ft tall, to stand in front of it and cover its fading stems.
- Montauk daisy: from mid September to late October, 3 ft tall, to stand in front of it and cover its fading stems.
What does feather reed grass 'Overdam' look like in winter?
Feather reed grass 'Overdam' turns the colour of straw and, left uncut, stands through the winter. Cut it down in late winter, before the new shoots come up.
More Calamagrostis
- Feather reed grass 'Avalanche' Calamagrostis x acutiflora 'Avalanche'
- Feather reed grass 'Karl Foerster' Calamagrostis x acutiflora 'Karl Foerster'
- Korean feather reed grass Calamagrostis brachytricha
In these guides
- Pet-safe plants for a sunny border
- Tall perennials and grasses for the back of a border
- Long-flowering plants: 12 weeks or more
Every fact on record
- Type
- Grass
- Size
- 4 ft (120 cm) tall, 18 in (45 cm) wide
- Plant
- 18 in (45 cm) apart
- Height class
- Moderately tall (3 to 4 ft)
- Place in the bed
- Back, or further forward: it is airy enough to see through
- Flowers
- Late June to mid September; feathery plumes; tan
- Leaves
- Fine texture, herbaceous; variegated
- Shape
- Upright, clumping
- Hardy in
- USDA zones 4 to 8
- Light
- Full sun, part sun
- Soil
- Average, evenly moist
- Water
- Moderate
- Feeding
- None needed
- Family
- Poaceae
Checked against NC State Extension. Flowering times are for zone 5: later in colder zones, earlier in warmer ones. Toxicity and spread information is a general gardening guide, not veterinary or medical advice, and invasive status varies by region. If a person or pet eats a plant, contact poison control or a vet. Check your local invasive species list before planting anything with a spread warning.