Where are the best places to site asters in the landscape?
Plant pink asters in areas you use frequently in the fall—near doorways, along paths or by the garage. Asters rejuvenate a fading autumn flower border, making a brilliant display when paired with tall grasses or the blue stalks of ‘Arendsii’ monkshood (Aconitum carmichaelii, Zone 3).
Should you plant asters in groups?
Absolutely! Depending on the size of the area, asters look best planted informally in groups of three, five or seven. Allow 45 to 60 centimetres between plants. Grouping them like this adds a powerful punch of colour, and helps plants hold each other up, too.
Any plant that prolongs the gardening season is a winner with me! Their long-lasting cut flowers are always the centrepiece of my Thanksgiving table.
- Most asters grow best in full sun (for better flowering, stronger stems and fewer disease problems) to part shade (especially woodland varieties).
- Will tolerate average to poor, dry soils, but to reduce powdery mildew, grow in moist, rich soil or plant mildew-resistant types.
- Mulch new plants with compost or shredded leaves in spring and fall.
- Pinch back or shear stems in early summer to delay flowering and produce a sturdier form that won’t need staking.
- Water deeply (2.5 centimetres) as needed.
- Divide every two to four years to keep plants vigorous, full and within bounds.