zxcvbob wrote:

David Shalita wrote:
How can I prevent black flies from living on a Gardena Bush? Safer soap
sppray is not helpful.

At one time, this plant had black fungus, but the
Bayer company systemic food has eliminated any reoccurance.

What can I spray to discourage black flies?

Thanks, Dave

I used to treat black fungus and tiny flies (I don't remember what color
they were) with dormant oil spray, at one-half strength.

Will give this a try.
These flies are large common house flies, not tiny gnats.

Thanks again, Dave