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written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published 11/1/13

My birthday is in September and I like having sapphires as my birth stone, but as a young girl I was disappointed that asters were my official “birth flower.” To me they lacked the beauty of roses, carnations, or other birth flowers. I’m happy to say that the garden asters of today have changed my feelings about asters. These fall flowering perennials bring color to the fading perennial garden and are great companions to chrysanthemums blooming at the same time.

The name aster is derived from the Greek word for “star” which is attributed to the centers of these small daisy-like flowers. In the language of flowers, asters supposedly symbolize love, faith, wisdom and color.

Asters are an easy-to-grow perennial that has few serious insect or disease problems. Like so many flowering perennials, they grow best when located in a full sun site with a well-drained, loamy soil.

There are two main types of aster along with a few minor types. The major types are New England asters and New York asters and they look very much the same. Both are very winter hardy and both are native to eastern North America. They are not considered aggressive or invasive.

Depending on the cultivar, New England asters (Aster novae-angliae) tend to be taller, growing from 3 to 6 feet tall. New England asters have thick hairy stems and hairy leaves. The hairs are irritating to the skin of some people. There are cultivars with red, blue-purple, violet, white or pink flowers produced above the leaves in late summer to early fall.

Because of their upright growth and height it is advisable to stake or provide some other type of support, especially considering our windy weather. To avoid staking the taller New England cultivars, pinch them back early in the growing season to encourage branching. Pinched plants will be shorter and bushier.

(What is meant by “pinching back? This is a gardening term that means using the fingernails on your thumb and forefinger to pinch off the tips of tender plant shoots. It is typically done to encourage branching below the shoot ends to make a plant more compact and to encourage more blooms.)

New York asters (Aster novae-belgii) are generally more popular and a bit shorter. Depending on the cultivar, they grow from 2 to 4 feet tall. Their stems are thinner and without the irritating hairs. You will want to stake taller cultivars. There are many purple to blue cultivars, but there are also ones in white and pink. They tend to bloom fairly late, often around the end of September and are sometimes referred to as the “Michaelmas daisy” because the Feast of St. Michael is observed on September 29th.

While New York asters are generally more popular than the New England ones, there is a notable exception. A real “star” of the garden is Purple Dome New England aster. Purple Dome is a compact mounded plant that grows 18 inches tall and 36 inches wide. It is a true “purple dome” in the fall, covered with bright purple semi-double flowers.

Once planted in your garden, asters don’t need much attention other than staking. If they grow well, they may need dividing every couple of years. If so, divide them in the spring. Problems to watch for include powdery mildew and aphids.

Published: 11/1/2013 1:52 PM



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