Aster Flowers: How to Grow and Care for Aster Flowers

Closely related to chrysanthemums, aster flowers (Asteraceae or Symphyotrichum) are great pollinators that are easy to care for and come in short and tall varieties. These perennials are fall garden bloomers. They most commonly sprout into lilac or purple daisy-like flower heads with yellow centers, although aster plants are capable of producing white flowers, pink flowers, blue flowers, and other colors. No matter which flower color you prefer, planting aster seeds is ideal if you want to keep your garden vibrant and eye-catching in the late summer through the fall.

There are more than a hundred different varieties of aster flowers, but they can be divided into a handful of main categories. Some types of asters are:

1. 1. New England asters: New England asters (Aster novae-angliae or Symphyotrichum novae-angliae) are generally purple asters that come in taller cultivars and are ideal for decorative sets of cut flowers. This category includes Purple Dome, Honeysong Pink, and Lyle End Beauty asters.
2. 2. New York asters: New York asters (Aster novi-belgii or Symphyotrichum novi-belgii) are pinkish asters that come in shorter cultivars and can flourish in a flower bed. This type includes Winston Churchill, White Lady, and Crimson Brocade asters.
3. 3. China asters: China asters (Callistephus chinensis) originate in the land of their namesake, but they’re regularly grown on other continents, such as North America and Australia. These flowers can sometimes grow to be a yard tall, so it’s worth considering planting asters like these toward the back of your garden.
4. 4. Heath asters: Heath asters (Aster ericoides or Symphyotrichum ericoides) are commonly white and among the most daisy-like of asters. Consider staking heath asters to prevent them from drooping.
5. 5. Smooth asters: Smooth asters (Aster laevis or Symphyotrichum laeve) are so called because of how unwrinkled they are to the touch. Remarkably resilient, these flowers can stay intact well into late November.

If you’re ready to plant asters in time for the next growing season, just follow these simple steps for a colorful garden full of fall flowers:

• Find the right spot. Asters prefer to grow in full sun if possible, though partial shade is acceptable. They should be placed in well-draining yet moist soil to ensure they can grow without fear of becoming unhealthy from too much or too little water. Give them a loamy environment and these hardy flowers will do most of the work.
• Choose a time that works for you. Choose any time to plant your asters so long as they’ll have time to begin growing before extreme heat or cold sets in. If you plant your asters in the early spring, you’re practically guaranteed to see them adding early fall color to your garden. That’s not the only option for you, however, as these robust, resilient flowers can take root and begin germination in most conditions. You can also plant them in late spring and early fall without much concern. Consulting the USDA’s directory of hardiness zones can help you come to a decision here.
• Nourish them appropriately. Asters need sustenance to survive and thrive. Water them well at the roots and establish early on your routine with mulch and fertilizer to set the asters up for success against weeds of all kinds.
• Water them well. Don’t let your good intentions get the best of you. Asters can actually be damaged by adding too much water into the mix. Always make sure to water them at the root and plant them in soil that’s capable of draining itself. This will prevent the new growths from succumbing to mold and other fungal issues and keep the blooms looking beautiful.
• Consider staking. Some asters stay relatively short, but others can grow to be several feet tall. If yours are on the larger side, it’s worthwhile to support them via staking to prevent them from drooping. This will help them grow to their greatest possible heights and ensure they are presenting their flowers well.
• Garden defensively. It may seem like tough love, but sometimes the best way to protect your asters for the next year is to cut them down to size before the winter. Make sure to give them mulch while you wait out the colder months. Deadheading asters can also be a useful means by which to keep them coming back stronger than ever.

Asters propagate easily by means of division. Their technical status as wildflowers indicates they’re more than capable of self-seeding the ground they’ve sprouted from for a return visit the following season. For germination within a garden, however, it’s wise to take a more hands-on approach for aesthetic reasons. In early spring, apply your preferred method of digging up a group of asters—including the roots—and divide that group into two or more sections. Then transplant the divisions wherever you please, being sure to space them out so they have ample room for new growth.

Asters are subject to many of the same pests and diseases as other flowers and plants. Insect assailants like aphids and lace bugs can commonly be repelled from your asters through the use of a pesticide. If you’re hoping to cultivate asters, you should also be ready for the appearance of fungal diseases like powdery mildew. Keep them out of unnecessarily damp conditions as a preventative measure and remove any unhealthy parts of the flower as soon as you notice them.

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