Noted: I searched my resources and the internet and found nothing on St. John’s wort susceptibility or resistance to verticillium wilt. So I consulted Brian Hudelson, director of diagnostic services for the University of Wisconsin-Madison Plant Disease Diagnostic Clinic. He did find one report of verticillium wilt on Hypericum from Poland. So he is assuming Hypericum is technically susceptible but feels it might be more like serviceberry (Amelanchier) that is technically susceptible but seems to be quite resistant.
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