New England aster 'Purple Dome'
Symphyotrichum novae-angliae 'Purple Dome' · Asteraceae
A compact New England aster that makes a low, wide cushion, hidden under deep violet daisies for a month in early autumn.
- Size
- 20 in tall, 2½ ft wide
- Zones
- 3 to 8
- Light
- Full sun
- Flowers
- Early September to mid October
- Pets
- No toxicity recorded
- Job in a bed
- Drift
A bed built around New England aster 'Purple Dome'
The planner designed this bed around New England aster 'Purple Dome' 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 966 that suit those conditions, and says below why New England aster 'Purple Dome' stands where it does.
The plants
- 1 New England aster 'Purple Dome' × 1, purple
- 2 Dianthus 'Kahori' × 9, pink
- 3 Winter heath × 13, white
- 4 Wild quinine × 5, white
- 5 Brown-eyed Susan × 5, yellow
- 6 Sea kale × 1, white
- 7 Ornamental onion 'Purple Sensation' × 3, purple
- 8 Grecian windflower × 10, blue
Why this plant
- Nothing here is unique to it. Its leaf, flower shape and colour are all on the plan already. Its case rests on where it stands and when it performs.
Why here
- In the middle. At 20 in it is seen over winter heath (10 in) in front of it.
- One plant. Three or more is usual for a plant of this kind, and reads better.
Why now
- In flower for 7 weeks. From early September to mid October.
- Closes the season. For its last two weeks nothing else on the plan is in flower.
Planned as an English border: 5 of the 6 groups (83%) are drifts, longer along the bed than they are deep. White is the colour seen most, on 3 of the 8 kinds grown for their flowers. Neither end outweighs the other: the visual weight is split 47 to 53, left to right.
The planner's own design check: 11 Excellent, 4 Good, 2 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 New England aster 'Purple Dome' 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.
It gives the colour of the tall asters without the staking or the bare legs. Mass it in front of goldenrod or switchgrass for the purple and gold of an American autumn.
- Autumn colour at the front and middle
- Late nectar for butterflies
- A hardy alternative to chrysanthemums
What to plant with New England aster 'Purple Dome'
Plants recorded as good partners for it, and what each pairing does:
- Goldenrod 'Fireworks': purple against yellow, opposite each other on the colour wheel, in flower together for six weeks; tall enough (3½ ft) to stand behind it.
- Switchgrass 'Shenandoah': its green leaves are a setting for the flowers, before and after; tall enough (4 ft) to stand behind it.
- Sedum 'Autumn Joy': in flower together for six weeks, from early September; bold leaves against its medium ones.
Questions about New England aster 'Purple Dome'
Does New England aster 'Purple Dome' need sun or shade?
New England aster 'Purple Dome' grows in full sun (6 or more hours of direct sun a day).
It wants ordinary well-drained soil, of average fertility, and a good soak in dry spells.
What zones does New England aster 'Purple Dome' grow in?
USDA zones 3 to 8. It is hardy to zone 3, which means it survives winter nights down to about −30 °F (−34 °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 New England aster 'Purple Dome' flower in my zone?
In zone 5 it flowers early September to mid 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 3 | Early September to mid October |
|---|---|
| Zone 4 | Early September to mid October |
| Zone 5 | Early September to mid October |
| Zone 6 | Early September to mid October |
| Zone 7 | Early September to mid October |
| Zone 8 | Early September to mid 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 New England aster 'Purple Dome' be planted?
24 in (60 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 2½ ft (75 cm), so a group knits into one patch.
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 New England aster 'Purple Dome' 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 one in one group.
Is New England aster 'Purple Dome' 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 New England aster 'Purple Dome'?
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 New England aster 'Purple Dome'?
New England aster 'Purple Dome' is over by mid October. These start as it finishes and carry the same spot on, so it never goes flat:
- Bodnant viburnum 'Dawn': from early November to late December, 10 ft tall.
- Common witch hazel: from mid October to late November, 15 ft tall.
What does New England aster 'Purple Dome' look like in winter?
New England aster 'Purple Dome' 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 New England aster 'Purple Dome' good for bees and butterflies?
New England aster 'Purple Dome' is visited by pollinators, specialist bees, butterflies, beneficial insects and songbirds.
It is a host plant: the caterpillars of pearl crescent feed on its leaves. A butterfly can only lay its eggs on its host plants, so these do more for it than any nectar flower.
It is native to the United States and Canada (this is a named variety of the native plant).
More Symphyotrichum
- Aromatic aster 'October Skies' Symphyotrichum oblongifolium 'October Skies'
- 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 York aster Symphyotrichum novi-belgii
- Smooth aster 'Bluebird' Symphyotrichum laeve 'Bluebird'
In these guides
- Pet-safe plants for a sunny border
- Native perennials for pollinators
- Garden plants native to Canada
- Plants for butterflies
- Plants for bees
- Plants that feed garden birds
- Plants that flower in fall
- Host plants for the pearl crescent
Zone guides: Zone 3 · Zone 4 · Zone 5 · Zone 6 · Zone 7 · Zone 8
Every fact on record
- Type
- Perennial
- Size
- 20 in (50 cm) tall, 2½ ft (75 cm) wide
- Plant
- 24 in (60 cm) apart
- Height class
- Medium short (18 to 24 in)
- Place in the bed
- Middle
- Flowers
- Early September to mid October; daisies; purple
- Leaves
- Medium texture, herbaceous; green
- Shape
- Mounding, clumping
- Hardy in
- USDA zones 3 to 8
- Light
- Full sun
- Soil
- Average, well-drained
- Water
- Moderate
- Feeding
- None needed
- Family
- Asteraceae
- Comes from
- Eastern North America
- Attracts
- Pollinators, specialist bees, butterflies, beneficial insects, songbirds
- Host plant for
- Pearl crescent
Checked against NC State Extension and VASCAN (plants of Canada). 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.