Marianne's Response
How to prune dianthus
Hi Marianne: I have a dianthus that is about 4 years old, and, unfortunately, I have never pruned it. It is still flowering beautifully, but has an ugly brown donut hole in the middle. I would like to cut it back to try to to get more green growth from the center. Could you tell me how to do this, and also can I take cuttings to start new plants?
Posted by wstrkmp on June 11, 2016
Marianne's Response
You can prune back that dianthus so that it is just six inches tall and hope for some fresh new growth - but most perennials have a short life span of about 5 to 7 years so your dianthus may be ready to return to the earth. You can take fresh cuttings from the mother plant however. Just snip off the top growth so you have a few stems about 8 inches long. Remove any flowers or buds. Strip off the foliage from the bottom half of the cutting and insert this end into a rooting medium of damp sand or perlite. You can also try to root them by sticking the cut end directly into garden soil. With some luck the cuttings should form roots in about six weeks.
Keep growing,
Marianne Binetti
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