Black spot on rose bushes. Using Mancozeb and immunox mix
When I mix the two in my sprayer should I use 1 tablespoon of each in two gallons of water. I think that is what you mean in the paper I read on you sight. Don't want to make my roses look worse than they do now with an over strong mix. Thank you
Certified GKH Gardening Expert
Yes, you add each product to the tank water as though it were the only thing being added. Per the label on the product. Keep two things in mind with this treatment. The mancozeb will leave a yellowish powdery residue on the rosebushes foliage as that is part of how it works. This spraying in severe attacks is best repeated every 5 to 7 days. Once attacked by black spot, the existing foliage will not be free from its black marks/spots. If the fungus is killed, the new foliage should not have anymore black spot damage or signs.