Plant library · Perennial Flowers
Aster alpinus
Alpine Aster is a compact perennial that forms a low, rounded presence about 1 foot tall and wide. Violet, daisy-shaped flowers arrive from late spring into early summer, giving small-scale beds a clear seasonal highlight without blocking views across the garden. Its modest stature suits planting plans that need a durable, flower-focused layer close to the ground.
Use Alpine Aster at the front of a sunny border, along the outside curve of a bed, or in the pockets of a rock garden. Its low mound reads best where flowers can be seen at close range, such as beside a path, near a patio edge, or in an alpine trough. Keep it in front of taller perennials and shrubs so it is not hidden when bloom begins.
Plant on 9-inch centers for a closely knit run of foliage and flowers. Each plant can reach about 1 foot wide, so this spacing allows neighboring mounds to meet and soften bare soil rather than remain as isolated dots. In a narrow border, reserve roughly 1 foot of bed depth for a single row and leave a path-side edge clear enough to reach the plants for seasonal cleanup.
Place it in full sun, where the low mound will receive open light rather than shade from nearby taller planting. Provide moderate water and a well-drained planting area; rocky, sandy, or raised portions of a bed can help keep the crown out of persistently wet ground. In heavier soil, avoid the lowest or slowest-draining part of the layout.[1][2]
The main floral display falls in late spring and early summer, so let neighboring later-season plants take over visually after the flowers fade. Deadheading keeps the planting tidier during the growing season. Cut stems back close to the ground in late autumn, and keep that access in mind when placing plants against rocks, edging, or other permanent features.[2]
Give each clump some open air rather than packing it tightly behind dense foliage or against a solid structure. Good circulation and well-drained soil are especially useful where foliar disease or wet winter soil is a concern. Hot, humid summer sites may be less accommodating, so favor an open, sunny position with drainage over a confined heat-trapping corner.[1]
Editorial content updated 2026-07-20.