What is the bug on my white flowers?

Hoplia beetle
also known as Rose Chafer or erroneously called Japanese Beetles.

These beetles are a nuisance on white and light colored flowers every spring. They are only here for a few weeks and unfortunately there is little to do about them. As a preventative in March you can treat your entire yard with grub control to get them before they hatch. Keep in mind that they can still fly in from your neighbor’s yards! Otherwise it is best to hand pick and deter them. Deter them with a white bucket that has a few inches of water in the bottom with a drop of soap. They are quite dumb and will be drawn to the white bucket and drown in the water. Spraying the plants with insecticide is quite wasteful as the spray has to contact them and more will fly in constantly.

Read more about the Hoplia Beetle here.