Rick from Branford Ct writes
I'm spraying for black spot on roses and I'm using a 4 gallon back pack sprayer, how many ounces per gallon?
Per the product label, for black spot on roses:
Mix 5-8 fl. oz. of Propiconazole 14.3 Fungicide 14.3 in 100 gals. of water and apply as a full coverage spray to the point of drip. Apply as needed, beginning when conditions are favorable for disease development. For blackspot, apply with a registered contact fungicide labeled for black spot.
That would break down to about 1.5 - 2.5 mL of concentrate per gallon of water.
Since this is a more commercial product, if you are treating home roses, then you may consider a formulation that is easier to measure for smaller applications, such as Fertilome Liquid Systemic Fungicide II:
https://www.domyown.com/fertilome-liquid-systemic-fungicide-ii-p-1540.html
This product is used at 1-2 tablespoons per gal of water for roses and flowers.
Answer last updated on: 06/21/2022