cobaea turning deep purple then yellowing
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.
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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