Purple aster stems only middle - divide? - Ask Extension
Hello,
This is the second year for a purple aster in a sunny location in my yard. Last fall there were numerous flowers and it was frequently visit...
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Purple aster stems only middle - divide? #884115
Asked September 05, 2024, 8:19 AM EDT
Hello,
This is the second year for a purple aster in a sunny location in my yard. Last fall there were numerous flowers and it was frequently visited by bumble bees. Sometimes bumble bees would sleep on the flowers overnight. This summer, the plant appeared to fall/spread out leaving only stems in the center of the plant (see picture 1). Later in August there were signs of new leaves in the center of the plant (see picture 2). My question is how to avoid this appearance of no leaves (only stems) mid summer? Or is this a typical growth pattern? Is it time to divide the plant? Should the plant be supported in some way? I would like to avoid the falling over, only stems left in the middle appearance. Suggestions? Thanks in advance.
Howard County Maryland
Expert Response
Hi Dan. This is a common problem with asters.
Assuming the plant has developed flowers since you took the photos (I'm guessing they were shot a while ago?), a short-term fix is to simply stake the flopping stems to show the flowers more promiently and to enhance the plant's overall appeance. Here is info from Maryland Extension on staking plants like this, https://extension.umd.edu/resource/why-some-flowering-plants-fall-over/
Then, next year, you'll want to start a program of pinching off the primary buds from mid-spring through early July. This process, also knowns as a Chelsea Chop, works to keep the plant bushy and controlled in size. You theoretically could do it just once, but pinching several times before July would work better. Here is an article on pruning asters from the University of Washington,https://depts.washington.edu/hortlib/pal/on-pruning-asters/#:~:text=control%20the%20height%20and%20shape,the%20aster%20can%20be%20shaped. I also found a useful YouTube video from the University of Missouri on pinching mums and asters, but I wasn't able to copy the link to this message. If you Google those search terms you should find it easily. Also, avoid applying fertilizer because excess fertilizer can make the plants tall and droopy.
Dividing up the plant into smaller pieces could also be beneficial, but since your plant is only one year old I'd be surprised if that was needed yet. More likely, that won't be needed for a couple of years.
Here is general information on the care of perennials from Maryland Extension, https://extension.umd.edu/resource/perennials/
Bob
Assuming the plant has developed flowers since you took the photos (I'm guessing they were shot a while ago?), a short-term fix is to simply stake the flopping stems to show the flowers more promiently and to enhance the plant's overall appeance. Here is info from Maryland Extension on staking plants like this, https://extension.umd.edu/resource/why-some-flowering-plants-fall-over/
Then, next year, you'll want to start a program of pinching off the primary buds from mid-spring through early July. This process, also knowns as a Chelsea Chop, works to keep the plant bushy and controlled in size. You theoretically could do it just once, but pinching several times before July would work better. Here is an article on pruning asters from the University of Washington,https://depts.washington.edu/hortlib/pal/on-pruning-asters/#:~:text=control%20the%20height%20and%20shape,the%20aster%20can%20be%20shaped. I also found a useful YouTube video from the University of Missouri on pinching mums and asters, but I wasn't able to copy the link to this message. If you Google those search terms you should find it easily. Also, avoid applying fertilizer because excess fertilizer can make the plants tall and droopy.
Dividing up the plant into smaller pieces could also be beneficial, but since your plant is only one year old I'd be surprised if that was needed yet. More likely, that won't be needed for a couple of years.
Here is general information on the care of perennials from Maryland Extension, https://extension.umd.edu/resource/perennials/
Bob
