Sedum problem - Ask Extension
We have a couple of previously healthy sedum plants which are showing sudden onset of disease today. One has blotchy leaves the other has tiny black b...
Knowledgebase
Sedum problem #404949
Asked June 05, 2017, 9:01 PM EDT
We have a couple of previously healthy sedum plants which are showing sudden onset of disease today. One has blotchy leaves the other has tiny black bugs (?aphids). Should we pull them out or try to treat them hoping other plants don't get infected?
Hennepin County Minnesota
Expert Response
Aphids
are tiny soft-bodied, pear-shaped insects. They feed by sucking sap from leaves.
They are often found on the underside of leaves. You can knock or hose them off with plain
water. You can spray the clusters of
aphids with insecticidal soap or pyrethrum spray.
If the blotches turn brown and scabby then it
may be powdery mildew. The following sites have pictures of powdery mildew on
sedum.
http://www.science.oregonstate.edu/bpp/Plant_Clinic/images/sedum_powderymildew08-43.htm
https://negreenhouseupdate.info/photos/sedum-powdery-mildew
Most sedums possess good disease resistance; however, S.‘Matrona’ is especially susceptible powdery mildew and should be avoided. High levels of humidity are conducive to powdery mildew development. Increase plant spacing to promote air movement around plants.
