How to Plant, Grow and Care for Asters

Looking to add some flowers to the fall garden? As other perennials are starting to slow down, asters are just getting started, adding color to the landscape and providing support for pollinators. Asters are long-lived perennials that are members of the Asteraceae or daisy family. Typically, you’ll start to notice them late in the summer, blooming in response to shorter days, with flowers that can range from blue to purple to white depending on the species. Among the more popular cultivars are 

New England aster ‘Purple Dome’ 

Bushy Aster ‘Wood’s Pink’ 

‘Kristina’ 

 

 

Asters can be grown in containers as annuals, on the porch or deck. For the best results in the long term, asters need to be planted in the perennial bed.  

 

Start by selecting a spot in the garden that receives a minimum of six hours of direct sunlight. Asters planted in less than full sun will grow tall and scraggly, with reduced flower size. Next, amend the planting site with organic material, such as Earth Essentials Sheep. Peat and Compost. The planting hole should be twice as wide as the container and half again as deep. Once the site is ready, place your garden mum in the planting hole, making sure the crown of the plant is at the same level it was in the container. Fill in around the plant with amended soil. Next, mix up a solution of Root Stimulator and water the aster thoroughly. Root Stimulator will help the plant establish a strong root system going into winter. Aster will generally lose their top growth after a hard frost and begin to go dormant for the winter. When this happens, they need to be cut back to a few inches above the ground.

Wait until the ground is cold - usually around Thanksgiving before adding a five-to-six-inch layer of mulch, such as bark fines.  Mulch will help retain moisture and keep the ground stable. Mountain Magic Soil Pep is a good choice for mulch.  

 

Through the course of the winter, water the asters every five to six weeks. This practice applies to all trees, shrubs and perennials in your landscape. The following spring, after the threat of frost has passed, start to remove the mulch gradually. You can also remove any dead vegetation that may remain. In some cases, you’ll find the plant has already begun to leaf out.  

 

Planted in the garden now, hardy asters will offer seasonal color as well as pollinator support for many seasons to come.