This is not a problem (for now) with my roses but something completely defoliated my salvia and marigolds. I put out two bowls of beer thinking it was the slugs and was surprised to see lots of beetle looking insects and a ton that looked like tiny grubs. After research on the web, they look like root weevils and and weevils larvae.

I also dug a few plants up and transplanted things and found a ton of these beetle looking things in the soil. I squished every one I could find.

My question is, should I continue to put beer out, or is there another way to control them? They have completely eaten two flats of marigolds and the salvia. I want help asap