Best Pre-Emergent on the Market
This is what professional landscapers use to control weeds and minimize labor. It's expensive, but it's much more effective than most any other pre-emergent on the market. Controls more weeds and lasts a fairly long time (9 months in rainy states, 12 months in dryer climates). You don't need to apply very much of it. Most people apply 2-3 times more than you need to. Get yourself a "Earthshaker" spreader by Earthway. Open it up to just 2.5 holes showing. And that's how much you need to apply. Just shake it over the ground. A 50 lb. bag will cover a pretty large amount of planting beds - more than most residential homes have these days.