Unfortunately, the only way to get rid of weeds in your beds is to carefully spray the weed and not the plant with an herbicide like Roundup. Roundup is Glysophate, save your money and buy the generic stuff, its exactly the same. The only other way is to pull them out of the ground with the roots manually. You can prevent the weeds from germinating all together with a granular product like Preen. Again, buy the generic product at Steins.