Answer: Fish emulsion contains a rapidly available nitrogen so there's no reason you cannot wait a week after using fish emulsion and then use the Bayer Advanced product. It contains slow release nitrogen along with disease and insect protection. It can take a week or two for the product to work its way up through the vascular system of your rose bush so don't expect immediate results with a systemic. In fact, products like these should be applied early in the season so they can be present within the plant before insects and diseases threaten. Another direction you can take is to put the Bayer product in storage until next spring (so you can use it earlier in the season before problems arise) and apply a neem oil based product now (such as Rose Defense). You spray this onto the plant and it has some residual effect so it deters future insect attacks in addition to immediate knock down. Just a thought -
Best wishes with your rose bushes.
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