Why are the leaves of my cobaea turning deep purple then yellowing in the centre? The past month has been very hot and humid. The plant received fertilizer a couple of times this summer. I've checked for aphids and there are none.
Cobaea Turning Deep Purple Then Yellowing
Certified GKH Gardening Expert
This could be a nutritional issue.
I also would treat with Neem OIl.
Epsom Salt may help.
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