I don't know how safe, but always used a spray bottle of rubbing alcohol when aphids got on my water lilies. It wouldn't harm the fish & evaporated quickly.

Dish liquid, vegetable oil, and water in a spray bottle.

Okay, thanks a lot. I had thought I would try my Murphy's Oil soap recipe on them, but was unsure as to the effect it would have on the baby cukes. I will try one recipe on one side of the trellis, and the other on the opposite side. To be continued .........

I had some growing at a friend's house and they were decimated by aphids. The underside of each leaf was covered. No idea what caused this. Tried Neem oil and other things, but there were too many of them.

I have never seen this many on ANY plant before, and it seems they just suddenly appeared. I have used the above treatment, but have no definitive results as yet.....