Autumn moor grass
Sesleria autumnalis · Poaceae
A neat, long-lived tuft of yellow-green leaves with narrow, silvery-white flower spikes in late summer. It keeps its fresh colour from spring until winter.
- Size
- 16 in tall, 18 in wide
- Zones
- 5 to 8
- Light
- Full sun to part shade
- Flowers
- Mid August to early October
- Pets
- No toxicity recorded
- Job in a bed
- Carpet
A bed built around autumn moor grass
The planner designed this bed around autumn moor grass when this page was made: a 12 × 6 ft (3.7 × 1.8 m) naturalistic planting in zone 6, part sun. It chose the other plants from the 708 that suit those conditions, and says below why autumn moor grass stands where it does.
The plants
- 1 Autumn moor grass × 4, cream
- 2 Bloody cranesbill 'Max Frei' × 8, pink
- 3 Robin's plantain 'Lynnhaven Carpet' × 20, lavender
- 4 Garden phlox 'David' × 3, white
- 5 Purple milkweed × 3, purple
- 6 Inkberry 'Gem Box' × 1, dark green leaves
- 7 Spring starflower × 5, blue
- 8 Surprise lily × 5, pink
Why this plant
- Part of the matrix. The low fabric of grasses and groundcovers that the taller plants come up through.
- The only spires. The others are open bowls, daisies, dense clusters and others. Shape reads at a distance, where colours blur.
- The only cream. Cream sits between stronger colours and calms them.
Why here
- Under the taller plants. It runs back between them as living mulch: there its job is to cover the soil, not to be looked at.
- 4 plants in one group. Massed, one kind reads as a single shape. Scattered, it would look spotty.
- Fine leaf against bold. Purple milkweed is beside it: the strongest contrast of leaf there is.
Why now
- In flower for 8 weeks. From mid August to early October.
- 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 naturalistic planting: low grasses and groundcovers, the matrix, make up 50% of the planted ground. The most in flower at one time is 3 kinds, in mid July. Robin's plantain 'Lynnhaven Carpet' is planted in four places along the bed, which gives it rhythm.
The planner's own design check: 14 Excellent, 3 Good. 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 autumn moor grass goes in a border
At 16 in it belongs at the front of a bed. In the planner's ten height classes it is short (12 to 18 in).
Its job: carpet. A groundcover planted in threes and fives to cover the soil: along the front, and just behind it.
The grass that modern naturalistic planting relies on: a low, luminous, yellow-green carpet through which perennials are scattered. It tolerates drought and part shade.
- A grassy matrix between perennials
- Massed groundcover in sun or part shade
- Edging
What to plant with autumn moor grass
Plants recorded as good partners for it, and what each pairing does:
- Betony 'Hummelo': flowers first, late June to early August, so the spot is never empty; spires rising out of its mound.
- Calamint: in flower together for eight weeks, from mid August; a low mound at the foot of its spires.
- Purple coneflower: in flower together for four weeks, from mid August; tall enough (3 ft) to stand behind it.
Questions about autumn moor grass
Does autumn moor grass need sun or shade?
Autumn moor grass grows in full sun (6 or more hours of direct sun a day), part sun (4 to 6 hours of sun, including some afternoon sun) and part shade (2 to 4 hours of sun, mostly in the morning).
It wants ordinary well-drained soil, of average fertility, and little watering once settled. Once settled in, it stands drought.
What zones does autumn moor grass grow in?
USDA zones 5 to 8. It is hardy to zone 5, which means it survives winter nights down to about −10 °F (−23 °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 autumn moor grass flower in my zone?
In zone 5 it flowers mid August to early October. As a summer flower it moves about half a week for every zone: earlier where it is warmer.
| Zone 5 | Mid August to early October |
|---|---|
| Zone 6 | Mid August to early October |
| Zone 7 | Early August to early October |
| Zone 8 | Early August to early October |
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 autumn moor grass be planted?
16 in (40 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 18 in (45 cm), so a group knits into one patch.
It grows 16 in (40 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many autumn moor grass plants do I need?
At 16 in apart, set out in staggered rows:
- 7 to fill 10 square feet (about 1 m²)
- 8 for a single row 10 ft (3 m) long
- 21 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as threes and fives, along the front and just behind it.
In the bed above, the planner used four in one group.
Is autumn moor grass 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.
Do deer eat autumn moor grass?
They may. NC State does not list it as resistant to deer or rabbits. Where they visit, protect it, or plant it among ones they avoid.
What flowers after autumn moor grass?
Autumn moor grass is over by early October. These start as it finishes and carry the same spot on, so it never goes flat:
- Japanese onion 'Ozawa': from early October to early November, 10 in tall, to stand in front of it and cover its fading stems.
- Chrysanthemum 'Sheffield Pink': from late September to early November, 2½ ft tall.
- Tatarian aster 'Jindai': from early October to early November, 4 ft tall.
What does autumn moor grass look like in winter?
Autumn moor grass holds some of its leaves into winter, more in a mild year or a sheltered spot, and they look tired by March. Cut the old ones off as new growth starts.
More Sesleria
- Blue moor grass Sesleria caerulea
- Moor grass 'Greenlee' Sesleria 'Greenlee'
In these guides
- Plants for dry shade
- Plants that grow near black walnut
- Pet-safe plants for a sunny border
- Pet-safe plants for shade
- Groundcover plants
- Ornamental grasses under 3 feet
- Plants with spires: vertical accents
- Plants that flower in fall
Every fact on record
- Type
- Grass
- Size
- 16 in (40 cm) tall, 18 in (45 cm) wide
- Plant
- 16 in (40 cm) apart
- Height class
- Short (12 to 18 in)
- Place in the bed
- Front
- Flowers
- Mid August to early October; upright spires; cream
- Leaves
- Fine texture, semi-evergreen; chartreuse
- Shape
- Mounding, clumping
- Hardy in
- USDA zones 5 to 8
- Light
- Full sun, part sun, part shade
- Soil
- Average, well-drained
- Water
- Low
- Feeding
- None needed
- Family
- Poaceae
- Comes from
- Southern Europe and Caucasus
- Stands up to
- Drought, black walnut, pollution
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.