Asters in New England

Another thing besides beautiful foliage that New England has in the fall is an abundance of native asters. In the Massachusetts County Checklist there are 27 species of Aster indigenous to Massachusetts. (Technically speaking, however, there are no more New World asters, they have been reclassified into a number of new genera including Doellingeria, Eurybia, Ionactis, and Symphyotrichum.)  A few of these native species, such as the purple New England Aster (Symphyotrichum novae-angliae) and Bushy Aster (S. dumosum) have become common in many gardens with cultivars such as ‘Alma Potschke’ and ‘Wood’s Purple’.  I would like to call attention to some commercially less common species that I have purposely grown or that have appeared around my house.

One of my favorites, which I have grown from seed is the Smooth Aster, Symphyotrichum laeve. This is a medium tall aster that grows in full to part sun and relatively dry soils. Its stems are strong enough that it does not always needed to be staked. However like many asters cutting back by 1/3 at the end of June gives a stronger, bushier plant. The flowers are usually a lavender blue measuring over 1” wide. In this photo are some freely seeded plants that show some variation in flower color. These are most commonly commercially available as the ‘Bluebird’ cultivar.

The Big-leaf Aster, Eurybia macrophylla, is early blooming and grows well in dry shade. My plants started blooming in late June and did not start going to seed until early September. Here we see the fuzzy seed heads and a few residual blooms. This species will spread by both seed and rhizomes. It forms dense mounds of foliage and can be used as a ground cover.  And It's still not bad looking when the seed heads replace the flowers.

Another shade tolerant species is the White Wood Aster, Eurybia divaricata. This species also grows in dry shade, e.g. upland woods. It blooming period is later than for the big leaf aster and it can be a vigorous spreader. This photo was taken at Mount Auburn Cemetery, but they are quite common in the woods in New England.

Two species that grow like weeds around my house are Heart-leaved Aster and Arrow-leaved Aster, Symphyotrichum cordifolium and S. urophyllum, respectively. Structurally these two asters are very similar. The most obvious difference is that the flowers of Heart-leaf asters tend toward blue-violet shades, while the Arrow-leaved asters are whiter.

In the garden they form clouds of light colored flowers that stand out against darker colored foliage.

I purchased the Heart-leaved aster thinking it would combine well with my yellow cone flowers (Rudbeckia), but the cone flowers are just passing as the aster begins to open up in mid-September. I need to find a later blooming yellow for this combination to work, such as the annual Black-eyed Susan (Rudbeckia hirta), or a late blooming Goldenrod like the ‘Fireworks’ cultivar (Solidage rugosa ‘Fireworks’). The Arrow-leaved aster just blew onto my property on its own.

 

The last aster that I have been working with is the Smooth Violet Prairie Aster (S. turbinellum). This aster is not native to New England, rather its home is in the Plains States. I got this plant for use in a parking lot island, where it gets no extra watering or special care, 4 years ago and it is still going strong. It has profuse blue-violet blooms from September to October on relatively stiff stems. The only care I give this plant is to cut it back by 1/3-1/2 in late June to keep it from getting too tall and flopping over.

 

My first preference was to use the Smooth Aster (a New England Native) on this site, but that plant was not available at the time of installation. I had only a single pot of Smooth Aster to put in at the time.  While it is still surviving there, the Prairie Aster is really doing well in that location (and the bees love it, too).