J justagirlart Well-Known Member Joined Jan 8, 2019 Messages 66 Reaction score 3 Sep 22, 2019 #1 I have recently had a phrag diagnosed with phytophthora. Aka plant killer. How can this be prevented in Phrags? Subdue and Truban are the best treatment. Can these be used on Phrags or will they kill a phrag?