Early spring is the best time to clean up perennial beds such as iris, day lilies, and sedum. Removing dead foliage prevents disease, root rot, insects, and it lets in needed light for new growth.

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Spring Clean-up of Perennial Beds

You know, many people like to do a fall clean-up of their garden. Once we’ve had a fall- freeze and everything has died back to below ground. But actually on most of our perennials, that’s a bad idea. Too many of them have hollow stems like this sedum here. You can see where it’s just been cleaned up. What happens is those hollow stems act like straws, and they carry moisture down into the plant below ground all winter long and it causes root rot. So, it’s really best to wait until spring to do clean-up when things start to emerge, and then cut it back and clean it up. You can see the sedums are starting to resprout.

In perennial plants like iris, particularly now when their new fronds are emerging, it’s important to remove the dead foliage for two reasons. One, it’s dead brown and looks ugly. So, we want to stay after it and remove all the dead foliage from out of here. And we want to remove any of the older leaves that show any signs of disease on them - the brown spots. If they’re allowed to remain, they’ll just spread and infest the new foliage here. So, we want to remove all of this old foliage.

On the day lily, you can see it really covers the new foliage. When it rains, it would stay moist in there, it would start to rot the plant, harbor disease, and also gives a place for insects to hide that would feed on it. By opening it up and getting the dead out of there, we improve the air circulation, we let more light into the new growth, so it’s not tall and spindly – trying to work it’s way through it. We start photosynthesis quicker, and it looks lot nicer and neater.

This feature story prepared with Alan Stevens, retired Kansas State University Research and Extension State Leader, Horticulture. For more information, visit your local county extension office or visit our website at KansasGreenYards.org.


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