Aster 'Mönch'

Sun

Full sun; tolerates light shade but may flower less and lean.

Water

Moderate; water during establishment and prolonged dry spells. Avoid persistently wet soil, especially in winter.

Soil

Well-drained, moderately fertile soil; tolerates chalk and a range of soil pH. Improve drainage in heavy clay before planting.

Height

2-3 ft (0.6-0.9 m)

Spread

1.5-2 ft (0.45-0.6 m)

Flowers

Midsummer to autumn; lavender-blue daisy flowers with golden-yellow centres.

Foliage

Green, slightly rough, lance-shaped leaves on branching stems; dies back in winter.

Growth

Moderate

Care needed

Low

• Pollinators
• Heat tolerant
• Disease resistant

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Easy

Toughness

Fairly tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   1 ft (0.3 m)

2. After 1 year

   1.5 ft (0.45 m)

3. After 2 years

   2 ft (0.6 m)

4. After 3 years

   2.5 ft (0.75 m)

   full size

About 3 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Safe

Growth rate

Moderate

• Water deeply during the first growing season, then during prolonged dry weather.
• Apply a thin layer of compost in spring; avoid heavy feeding, which encourages floppy stems.
• Keep mulch clear of the crown and prevent winter waterlogging.
• Fit a low support in spring if the site is exposed or the soil is rich.
• Divide congested clumps in spring when flowering declines, usually every three to four years.

Pruning. Cut dead stems to just above ground level in late winter or early spring before new shoots lengthen. Snip off spent flowers during the growing season if you want a tidier display.

Late winter

Cut down dead stems before new growth starts.

Spring

Plant or divide clumps once the soil is workable, keeping the crown at soil level.

Mid-spring

Apply a thin compost mulch and install discreet supports where needed.

Summer

Water during prolonged dry spells, directing water to the soil rather than the leaves.

Midsummer to autumn

Remove faded flowers if desired and check young growth for slugs and snails.

Late autumn

Leave stems standing if you like their winter structure, and check that water drains away from the crown.

• Plant in repeated groups through the middle of a sunny mixed border for a long ribbon of lavender-blue.
• Combine with feather reed grass and stonecrop for contrasting flower shapes and late-season structure.
• Pair with yellow yarrow or coneflowers for a clear blue-and-yellow summer scheme.
• Use beside a sunny path or seating area where its flowers and visiting pollinators can be seen closely.

Garden styles it suits: English country, Cottage garden, New perennial (prairie), Pollinator garden, Blues and silvers and Dry gravel garden.

Plant it with: Feather reed grass, Stonecrop, Yarrow, Purple coneflower, Russian sage and Meadow sage.

Wildlife: The open flowers provide nectar and pollen for bees, butterflies and other flower-visiting insects over a long season.

• Crown or root rot in wet soil: improve drainage or move the plant to a raised bed; keep winter mulch away from the crown.
• Slugs and snails eating emerging shoots: inspect at dusk, remove pests and use labelled wildlife-conscious controls if necessary.
• Powdery mildew, although relatively uncommon on this cultivar: provide sun and airflow, water during drought and remove badly affected leaves.
• Flopping stems in shade or rich soil: move to a sunnier position, reduce feeding and add a low support early in the season.

Not known to be toxic to people, cats, dogs or horses. No part is recognised as poisonous, but it is an ornamental plant rather than a food plant.

• Italian aster (Aster amellus)

  One of its parent species; usually forms a shorter, more compact plant with a more concentrated late-summer flowering period. Named cultivars can be difficult to distinguish without a label.

• New York aster (Symphyotrichum novi-belgii)

  Typically flowers later and has smoother leaves whose bases clasp the stems; many forms spread more vigorously than the clump-forming 'Mönch'.

• New England aster (Symphyotrichum novae-angliae)

  Usually taller, with conspicuously hairy stems and clasping leaves, and generally flowers later in the season.

Aster comes from the Greek for 'star', referring to the flowers, while frikartii honours the Swiss breeder Frikart and 'Mönch' names a Swiss mountain.

Propagation. Divide established clumps in spring or take basal cuttings from young spring shoots. Seed will not reliably reproduce the named cultivar.

Accepted botanical name

Aster frikartii

Sources: GBIF (CC BY 4.0). The care and design notes are LandscapeGPT's own.