Symphyotrichum novae-angliae 'Purple Dome'
(previously known as Aster novae-angliae)
Overview
Uses: Front and middle of sunny borders, mass planting and drifts, pollinator gardens, outdoor containers and large planters, autumn seasonal displays.
Benefits: A compact selection of the New England aster that solves the one real problem with the species — it stays low and dense instead of stretching to four feet and flopping. Deep purple daisies with gold centers cover the entire mound in early fall and hold for several weeks.
USDA Hardiness Zones: 4–8
Sun: Full Sun
Life Cycle: Hardy Perennial
Growth Habit: Mounding, Clumping — dense low dome from a tight crown
Bloom Color: Deep Purple
Mature Height: 1.5–2 ft.
Mature Width: 2–3 ft.
Bloom Season: Late summer through fall
Growth Rate: Moderate
Summary
The New England aster is one of the great fall perennials and also one of the floppiest. Purple Dome keeps the flower and loses the flop.
It builds through summer as a low green cushion, no more than knee high, and then in late summer the whole thing disappears under bloom — small daisies in a saturated blue-purple with bright gold centers, packed tightly enough that the foliage is hard to see. The display runs three to four weeks and lands exactly when the rest of the border is winding down.
The mound holds its shape through wind and rain without staking, which is what makes it usable at the front of a bed or in a container where the species version would need cutting back twice a summer to stay upright.
Late-season asters are among the most valuable nectar plants in the garden. This one is heavily worked by bumblebees, and monarchs moving south in September and October feed on it regularly.
Care
Purple Dome New England Aster Care
Plant in full sun. Six hours minimum, more is better. In part shade the mound loosens, the stems stretch, and the plant loses the compact habit it was selected for.
Give it average, well-drained soil with steady moisture. New England asters resent drought at the root more than most fall perennials, and dry soil in midsummer causes the lower leaves to brown and drop before bloom.
Water regularly through the first season, and during dry spells thereafter. Good air movement around the plant reduces powdery mildew, which is common on the species and much less of an issue on this selection.
Feed lightly if at all. One spring application of slow release fertilizer is sufficient; rich soil or heavy nitrogen undoes the compact habit.
No pinching is required — that is the point of this selection. Cut the plant to the ground in late winter, and divide every three or four years in spring if the center begins to open up.
In containers, water more often than you would in the ground and use a pot wide enough for the mound to fill out. Plants hardy in the ground may require winter protection when grown in containers in colder zones.
Size
What Size is the Purple Dome New England Aster for Sale Online?
Our Purple Dome New England Aster ships in a greenhouse-grade grow pot and is appropriately sized for its container at the time of shipment. If you have specific sizing or planting questions, please contact us.
How Large Does Purple Dome New England Aster Grow?
Purple Dome holds at about a foot and a half to two feet tall and spreads two to three feet wide, forming a rounded cushion roughly twice as wide as it is tall. Space twenty-four inches apart for a continuous drift.
Additional Information
What are some common names for this plant?
The most widely used names, in rough order of familiarity, are:
- Purple Dome aster
- New England aster
- Michaelmas daisy
How is this different from a regular New England aster?
Size and posture, mainly. The straight species reaches three to five feet and typically needs staking or a midsummer cutback to stay upright. Purple Dome tops out around two feet, holds a dense rounded shape on its own, and carries a deeper, more uniform purple. Bloom time and pollinator value are essentially the same.
Is it a true native?
It is a nativar — a named selection of Symphyotrichum novae-angliae, which is native to eastern and central North America. The parentage is entirely from that native species; only the compact habit was selected for. See our Native Plants of North America collection for straight species and other selections.
Does it get powdery mildew?
Far less than the species, but it is not immune. Mildew shows up on lower leaves in humid summers, especially where plants are crowded or dry at the root. Space plants for air movement, water at the base rather than overhead, and keep the soil from drying out completely. It is a cosmetic issue and does not affect bloom or winter survival.
What pairs well with it?
It reads best against warm colors and strong fall foliage — goldenrods, black-eyed Susans, switchgrass, and low ornamental grasses that catch late light. See our Perennials collection for companions that bloom at the same time.
