The New England Aster (Aster novae-angliae) has daisy like flowers that offer late-summer and autumn interest. It is a perennial that is hardy to zones 4-8, and has a fine texture with a nice upright form. Asters liven up your yard and garden at times where color is getting a slim.
The aster prefers full sun and fertile soil that stays moist. The daisy-like, light violet blooms have a yellow center. The bloom time is in late summer into autumn. It has abundant 5” long leaves are medium green and lance shaped. You will find that their lower leaves will sometimes fall off in the summer.
Asters may require staking to remain upright and should be placed where the foliage can be supported either by stakes or other plants. Asters look great in the back of borders, in a cottage garden, or, in wetland areas. Their blooms attract butterflies and are excellent fresh cut flowers. Good garden companions include ‘Snowbank’boltonia, purple-flowered Russian sage, and rosemary.
New England asters should be planted 18-24” apart in spring or fall. Apply slow-release granular plant food at the time they are planted, or you can use a soluble fertilizer later after the plants get established. The aster will tolerate dry soil once established but performs better in moist soils. You should water it deeply when the soil does dry out.
It is advisable to mulch asters in the summer and winter time to prevent excess loss of moisture and to add nutrients to the soil. Usually about 3” of vegetative mulch will be enough.
Asters are very susceptible to diseases. Root rot is possible if the soil is too we, and powdery mildew is likely if the soil and air are too dry. Fungal leafspot is also common to asters. Regular fungicidal treatments are needed unless the plant is at the rear of the border where the foliage is not readily visible.
Other Aster Varieties
Frikart’s aster ( A. x frikartii) has deep violet blooms with an orangish-yellow center and reaches up to 30 inches high and 15 inches wide. ‘Monch’ is a popular cultivar. New York aster (A. Novi-belgii) reaches 4’ high and 3’wide. Its blooms are violet blue and appear in late summer into fall. The Alpine aster (A. Alpinus) has violet blooms with a deep yellow center in early and midsummer. The plants reach 10” high and 18” wide.
Propagation of Asters
Asters will need to be divided every 2 years in spring or fall to maintain its vigor and to control its growth. Dig around the root clump and lift it up. Use a sharp spade to slice through the root system, much as you do with dividing shrubs and other plants. Reset the healthy roots and top shoots, then water and mulch.