Yellow leaves on newly planted Knock Out Roses
Knock Out Roses were planted 1st of May, 2016 and were doing great but now, July 16th, the leaves are turning yellow then brown then dying. They are planted around a very large Oak tree which is encircled with a landscape border and has fabric and black mulch. They get some some but it is mosted shaded. The soil seems good but when I pulled up the fabric there was a lot of bug action going on. I have gone from hand held watering to using a soaker hose. Also, I sprayed them with Neem Oil. Nothing is helping. It is gradually getting worse.
Navarro County Texas
Knock Out Roses can tolerate some shade but they need at least six to eight hours of sun every day. You need a least a foot of space around the rose bush for good air circulation. I would suggest moving the rose bush out from under the canopy of the tree. When you water, try to keep the leaves dry. Too much watering can cause the loss of leaves and promote root disease. Let the plant dry out between watering again. Using Neem oil in extreme temperatures could cause the leaves to burn in the hot sun. You can access information from Texas A & M Agrilife extension service, Easy Care Roses.