Asters (Aster spp.) usually grow as perennial plants. There are many species, however, and about 200 cultivars, with plant heights ranging from a few inches to 12 feet tall. Aster flower colors can be various shades of blue, pink, purple, red, white or yellow. Most of them bloom in the fall but there are some species and cultivars that bloom at other times of the year. There is even one aster that blooms in the winter. With careful selection, there can be asters blooming in your garden year-round.
Alpine asters (Aster alpines) grow to a height of 6 to 12 inches and bloom from mid-spring to early summer. Their daisy-type, 1-inch-diameter flowers have purple-blue petals and yellow centers. While these are considered hardy in U.S. Department of Agriculture plant hardiness zones 4 to 9, they may not thrive in areas with hot, humid summers. A planting site with afternoon shade may help the plants survive in hot-summer climates. East Indies asters (Aster tongolensis) grow to a height of 1 to 2 feet and bloom from late spring to midsummer. Their flowers are 2 inches in diameter with violet petals and orange centers. They are hardy in USDA zones 5 to 8 and prefer a full sun exposure.
The “Monch” Frikart’s aster hybrid (Aster x frikartii “Monch”) and the “Rudolf Goethe” Italian aster hybrid (Aster amellus “Rudolf Goethe”) begin blooming in midsummer. “Monch” grows to a height of 2 to 3 feet with 2-inch-diameter flowers that have lavender-blue petals and yellow center discs. They are hardy in USDA zones 5 to 10. In most climates within these zones, they bloom until mid-fall; in warmer areas they may continue to bloom into the winter in spite of light frost. “Rudolf Goethe” grows to a height of about 2 feet with 1 1/2-inch diameter dark lavender flowers. It is hardy in USDA zones 5 to 8 and continues to bloom through the end of summer. Both of these asters grow best in a full sun exposure.
The “Snow Flurry” heath aster hybrid (Symphyotrichum ericoides “Snow Flurry”) and the “Jindai” tatarian aster hybrid (Aster tataricus “Jindai”) bloom from early to mid- or late autumn. “Snow Flurry,” often used as a ground cover, grows to a height of 4 to 6 inches and width of up to 1 foot. It produces 1/2-inch white daisy-type flowers with yellow centers and is hardy in USDA zones 3 to 9. “Jindai” grows to a height of 3 to 4 feet and produces 1-inch diameter purple flowers with yellow centers. It is hardy in USDA zones 4 to 8. Both of these asters prefer full sun, but “Snow Flurry” can be grown in light partial shade.
Climbing aster (Ampelaster carolinianus syn. Symphyotrichum and Aster carolinianus) is a vining plant, hardy in USDA zones 6 to 11, that begins blooming in late summer. It will continue blooming through winter in USDA zone 8 and above. The pale purple or pink flowers are 2 inches in diameter with yellow to orange center discs. They can be grown in full sun or shade and must be attached to a support structure because they do not have climbing tendrils.
- University of Vermont: Perry’s Perennial Pages: Aster
- Missouri Botanical Garden: Heterotheca Camporum
- University of Illinois, Urbana-Champaign: Crop Sciences Department: Aster Alpinus
- Missouri Botanical Garden: Aster Alpinus
- University of Missouri Extension: Missouri State University: The Berry Basket
- Chicago Botanic Garden: Plant Evaluation Notes: A Comparative Study of Cultivated Asters
- Floridata: Aster x Frikartii
- Missouri Botanical Garden: Aster x Frikartii “Monch”
- Missouri Botanical Garden: Aster Amellus “Veilchenkonigin” Violet Queen
- Missouri Botanical Garden: Symphyotrichum Ericoides “Snow Flurry”
- Missouri Botanical Garden: Aster Tataricus “Jindai”
- Stetson University: Native PlantWeb Site: Aster Carolinianus Walt.
- University of Florida: IFAS Extansion: Clay County Contact
- North Carolina State University: JC Raulston Arboretum: Connoisseur Plants -- 1997
- University of California: UC Master Gardeners Napa County: Healthy Garden Tips: Gardening for Butterflies
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