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Pruning asters: Tips on how to do it right if you want to stimulate lush growth.

The aster is a hardy perennial known for its many small, daisy-like flowers. In this article, you’ll learn how to properly prune asters to control their growth, limit self-seeding, encourage flowering, improve air circulation and maintain vigor.

Pruning asters – tips on how to do it right

Cutting asters - tips on how to do it right

Pruning asters is a must if you want to keep these perennial flowers healthy and blooming profusely. It’s also useful if you have asters that are growing too much and overgrowing your flower beds. To do it right, you just need a few tips.

Cutting asters is only necessary in winter to a limited extent.

Asters are usually cut back after flowering. But garden enthusiasts know that the plant’s stems provide some protection from low temperatures. So at the end of the growing season, cut back all stems to about 5 inches above the ground and discard the remains. In addition, this will keep the garden clean and prevent overwintering pathogens and pests.

Cut faded asters: But, if you haven’t removed the spent blooms during the growing season, you’ll have masses of fluffy seed heads that can spread throughout the landscape. Native seeds produce true replicas of their parents, but hybrids can produce different results, non-viable seeds, or no seeds at all. Be sure to mark the location of plants so you know where they are next spring.

Tip. It’s best to cut back asters only to just above the root system in spring.

Divide in spring for more vitality

This type of pruning is for manageability and vigor. When dividing, plants are dug up in spring and the thick rhizomes and fibrous roots are cut to divide a plant into two or more individual plants. The divisions are then replanted as desired.

In this way, gardeners can keep garden flora within set boundaries rather than letting them run wild at will. It also improves air circulation, which greatly curbs the development of fungal diseases to which asters are susceptible.

Cutting asters for bouquets stimulates the flora.

One way to stimulate lush growth is to cut flowering stems indiscriminately to make bouquets and vase arrangements. When you cut the stems, the flora is encouraged to form new stems and produce even more flowers.

Use this technique to restore balance to a plant with wayward, leggy stems. If you are removing the stems to enjoy as cut flowers, this is an excellent way to preserve the shape.

Cut off the head to encourage flowering.

Deadheading is the process of cutting an entire stem down to its origin once all the flowers on it have bloomed. Removing spent stems keeps plants looking fresh, prevents seed set and self-seeding, and stimulates new flowering.

Prune into shape to promote growth

Tall varieties are notorious for becoming very leggy and needing to be pruned late in the growing season. To encourage a more compact growth, prune off the soft shoot tips in late spring to early summer to remove no more than one-third of the total height. This provides shorter, side-branching growth that is bushier and requires less frequent pruning.

When you prune asters this way, they are a better companion for other plants in mixed groups because they don’t topple over and dominate.

More tips – prune asters on dry mornings.

Whether you’re pruning, defoliating or cutting back asters for vases, it’s best to do it on a dry morning after the dew has evaporated. Why? Cutting the stems causes wounds in the plants, making them more susceptible to pests and diseases. These plants are susceptible to fungal diseases that are activated by moisture, and open stem wounds are ideal entry points for disease.

In addition, plants that have been cut are temporarily stressed. In the morning, they are likely to be less dehydrated and already stressed, a condition that also makes them more susceptible to insects and pathogens.

Use sharp, clean clippers

Finally, keep all cutting tools sharp and clean. Dull tools cause fuzzy cuts that can expose excess plant tissue, leading to poor wound healing and increasing susceptibility to pests and infections. Loppers and shears that are not clean can transfer pathogens from plant to plant, affecting the entire garden.

Wear gloves and disinfect tools with a 10 percent bleach solution in water. Clean them before and after use. Rinse them thoroughly and dry all tools before putting them away.

Love your asters: Knowing how to prune your plants can help you control their size, spread and seed drop. And while some species can grow quite large, compact varieties offer manageable alternatives. And even if you don’t want to tame their wild and woolly nature, pruning for vases and dividing are still excellent ways to promote optimal blooming, prevent crowding and restore their robust nature.

In addition to asters, check out other typical fall flowers that are still suitable for your balcony here!