A Late-Season Aster Border with Penstemon and Feather Reed Grass

A Vibrant Fall Border with Asters, Penstemon, and Feather Reed Grass

This colorful border shows how richly a late-season planting can perform. Masses of asters in lavender-blue, violet, and pink fill the foreground and middle of the border, while the cerise flower spikes of Penstemon ‘George Home’ weave through them. Behind and between the flowers, the upright blond plumes of Calamagrostis × acutiflora ‘Karl Foerster’ bring structure and lightness.

The planting relies on repetition rather than strict formality. Lower, mounding asters create broad drifts near the front, medium-height selections fill the middle, and taller asters and grasses rise above them. The result feels abundant and relaxed, yet still coherent because the same few plants are repeated throughout.

Main plants used: Aster × frikartii ‘Mönch’, Aster novae-angliae ‘Rosa Sieger’, Aster novae-angliae ‘Violetta’, Aster novae-angliae ‘Lou Williams’, Penstemon ‘George Home’, and Calamagrostis × acutiflora ‘Karl Foerster’

Key Takeaways

Why This Border Works

The asters do most of the heavy lifting, but not all in the same way. Aster × frikartii ‘Mönch’ forms soft, spreading mounds toward the front, while ‘Rosa Sieger’ and ‘Violetta’ add fuller color through the middle. Taller still, ‘Lou Williams’ gives the border height and a looser, more architectural feel.

Penstemon ‘George Home’ changes the rhythm of the planting. Its upright cerise flower spikes cut through the rounded masses of aster flowers and stop the border from becoming too uniform. The grass does something similar in a quieter way. The upright straw-colored plumes of Calamagrostis ‘Karl Foerster’ add a vertical accent and keep the border attractive even as some flowers begin to fade.

The color combination is bold, but it works because the forms are varied. The asters bring a cloud of starry flowers, Penstemon adds vertical punctuation, and the grass introduces a calm neutral note that balances the brighter pinks and purples.

Using the Main Plants

Aster × frikartii ‘Mönch’ is the best choice near the front, where its relaxed habit and lavender-blue flowers can spill slightly into the border edge.

Aster novae-angliae ‘Rosa Sieger’ and ‘Violetta’ form the middle body of the planting. Their fuller growth and stronger pink and violet tones help carry the display across the border.

Aster novae-angliae ‘Lou Williams’ should be used more sparingly, in small groups or repeated clumps, so that it rises above the others without forming a solid wall.

Penstemon ‘George Home’ adds bright cerise spires and a very different flower shape. Repeat it in smaller groups so those vertical notes appear in several places.

Calamagrostis ‘Karl Foerster’ provides the upright framework. Use it behind and among the flowering plants so the pale plumes emerge through the border rather than sitting in a separate row.

Planting Recipe

Care at a Glance

A Few Things to Keep in Mind

This is a sunny border for the second half of the season. It is most effective when planted in generous drifts rather than in small isolated clumps. It is also better described as relatively low maintenance rather than maintenance-free, since asters can benefit from pinching or staking in richer soils.

Most of these plants are often passed over by deer and rabbits, but no planting is completely browse-proof. Even so, the combination is practical, colorful, and easy to adapt – a very good model for a cheerful late-summer to fall border.