Frost Aster

Symphyotrichum pilosum

Frost aster is named for the fact that it blooms right up to the first hard freeze -- and sometimes beyond. The tiny white flowers with yellow centers cover the plant in a white haze from September through November, creating a cloud effect that reads beautifully from a distance. The stems are slightly hairy, giving the plant its species name 'pilosum,' and the fine texture of the foliage and flowers makes it an effective softening companion to coarser fall perennials. This is the field and meadow aster that naturalizes freely -- a high-energy, self-sufficient species that does serious ecological work as a late-season fuel stop for monarch butterflies, migrating warblers, and goldfinches. In a naturalized garden or meadow it will spread to fill gaps, which is mostly a good thing.