Aromatic aster 'October Skies'
Symphyotrichum oblongifolium 'October Skies' · Asteraceae
A dense, low dome completely covered in lavender-blue daisies in October. It thrives in dry, poor soil and never needs staking.
- Size
- 20 in tall, 24 in wide
- Zones
- 4 to 8
- Light
- Full sun
- Flowers
- Mid September to late October
- Pets
- No toxicity recorded
- Job in a bed
- Drift
A bed built around aromatic aster 'October Skies'
The planner designed this bed around aromatic aster 'October Skies' when this page was made: a 12 × 6 ft (3.7 × 1.8 m) English border in zone 6, full sun. It chose the other plants from the 715 that suit those conditions and its dry soil, and says below why aromatic aster 'October Skies' stands where it does.
The plants
- 1 Aromatic aster 'October Skies' × 3, blue
- 2 Cheddar pinks 'Tiny Rubies' × 19, pink
- 3 Sea thrift × 8, white
- 4 False sunflower 'Summer Nights' × 3, yellow
- 5 Little bluestem 'The Blues' × 3, tan
- 6 Silver sage × 1, silver leaves
- 7 Star of Persia × 3, purple
- 8 Schubert's allium × 3, pink
Why this plant
- A classic partner for little bluestem 'The Blues'. Both are on this plan. A pairing gardeners have proved outranks a general rule.
- The only blue.
Why here
- At the back. At 20 in it is the step between silver sage (12 in) in front and little bluestem 'The Blues' (3 ft) behind: each is seen over the one before.
- A step in the back row. Next to false sunflower 'Summer Nights' (3½ ft) and little bluestem 'The Blues' (3 ft): no two neighbours there are the same height, so the back steps up and down like a skyline.
- 3 plants in one group. Massed, one kind reads as a single shape. Scattered, it would look spotty.
Why now
- In flower for six weeks. From mid September to late October.
- Closes the season. For its last three weeks nothing else on the plan is in flower.
Planned as an English border: 5 of the 7 groups (71%) are drifts, longer along the bed than they are deep. False sunflower 'Summer Nights' and little bluestem 'The Blues' anchor the back corners of the bed: the tallest plants on the plan stand there. Cool colours (blue, pink and purple) with yellow as the warm note, and white and tan to calm things between them.
The planner's own design check: 11 Excellent, 6 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 aromatic aster 'October Skies' goes in a border
At 20 in it belongs in the middle of a bed. In the planner's ten height classes it is medium short (18 to 24 in).
Its job: drift. Planted in a small group of three or five, and repeated further along in the other number.
A neat mound all summer, then a solid dome of blue when almost nothing else is flowering. It is the easiest aster of all: no mildew, no flopping, no bare stems.
- The best aster for dry soil
- Late colour at the front of a bed
- The last nectar of the year
What to plant with aromatic aster 'October Skies'
Plants recorded as good partners for it, and what each pairing does:
- Little bluestem: its blue-green leaves are a setting for the flowers, before and after; tall enough (3 ft) to stand behind it; happy in the same dry soil.
- Sedum 'Autumn Joy': in flower together for four weeks, from mid September; bold leaves against its fine ones; happy in the same dry soil.
- Goldenrod 'Fireworks': blue against yellow, opposite each other on the colour wheel, in flower together for four weeks; tall enough (3½ ft) to stand behind it.
Choosing between it and a look-alike? New England aster vs Aromatic aster 'October Skies'.
Questions about aromatic aster 'October Skies'
Does aromatic aster 'October Skies' need sun or shade?
Aromatic aster 'October Skies' grows in full sun (6 or more hours of direct sun a day).
It wants dry, sharply drained soil, of average fertility, and little watering once settled. Once settled in, it stands drought.
What zones does aromatic aster 'October Skies' 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 aromatic aster 'October Skies' flower in my zone?
In zone 5 it flowers mid September to late October. As an autumn flower it keeps much the same dates in every zone: it answers to shortening days and cool nights more than to the warmth of spring.
| Zone 4 | Mid September to late October |
|---|---|
| Zone 5 | Mid September to late October |
| Zone 6 | Mid September to late October |
| Zone 7 | Mid September to late October |
| Zone 8 | Mid September to late 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 aromatic aster 'October Skies' be planted?
24 in (60 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 20 in (50 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many aromatic aster 'October Skies' plants do I need?
At 24 in apart, set out in staggered rows:
- 3 to fill 10 square feet (about 1 m²)
- 6 for a single row 10 ft (3 m) long
- 10 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as a group of three or five, with a second group further along in the other number.
In the bed above, the planner used three in one group.
Is aromatic aster 'October Skies' 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 aromatic aster 'October Skies'?
Mostly not. NC State lists it as resistant to deer and rabbits. No plant is proof against a hungry deer in a hard winter, but this one is low on the menu.
What does aromatic aster 'October Skies' look like in winter?
Aromatic aster 'October Skies' dies down, but leave the stems standing: the seed heads stand through the winter, and songbirds eat the seed. Cut them down in early spring, before the new shoots come.
Is aromatic aster 'October Skies' good for bees and butterflies?
Aromatic aster 'October Skies' is visited by pollinators, butterflies and songbirds.
It is native to the United States (this is a named variety of the native plant).
More Symphyotrichum
- Aromatic aster 'Raydon's Favorite' Symphyotrichum oblongifolium 'Raydon's Favorite'
- Aster 'Wood's Purple' Symphyotrichum 'Wood's Purple'
- Blue wood aster Symphyotrichum cordifolium
- Calico aster 'Lady in Black' Symphyotrichum lateriflorum 'Lady in Black'
- Heath aster 'Snow Flurry' Symphyotrichum ericoides 'Snow Flurry'
- New England aster Symphyotrichum novae-angliae
- New England aster 'Alma Pötschke' Symphyotrichum novae-angliae 'Andenken an Alma Pötschke'
- New England aster 'Purple Dome' Symphyotrichum novae-angliae 'Purple Dome'
- New York aster Symphyotrichum novi-belgii
- Smooth aster 'Bluebird' Symphyotrichum laeve 'Bluebird'
In these guides
- Deer-resistant perennials for full sun
- Rabbit-resistant plants
- Drought-tolerant perennials for full sun
- Pet-safe plants for a sunny border
- Native perennials for pollinators
- Plants for butterflies
- Plants that feed garden birds
- Plants that flower in fall
- Plants with blue flowers
Every fact on record
- Type
- Perennial
- Size
- 20 in (50 cm) tall, 24 in (60 cm) wide
- Plant
- 24 in (60 cm) apart
- Height class
- Medium short (18 to 24 in)
- Place in the bed
- Middle
- Flowers
- Mid September to late October; daisies; blue
- Leaves
- Fine texture, herbaceous; green
- Shape
- Mounding, clumping
- Hardy in
- USDA zones 4 to 8
- Light
- Full sun
- Soil
- Average, dry and sharply drained
- Water
- Low
- Feeding
- None needed
- Family
- Asteraceae
- Comes from
- U.S.A. to North East Mexico
- Attracts
- Pollinators, butterflies, songbirds
- Stands up to
- Deer, rabbits, drought, poor soil
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.