Scott's Weed and Feed is the best fertilizer and weed killer combination. The easy-to-spread granules offer an application process that is simple for the average homeowner, yet effective enough to be mistaken for a professional job. Spring is the best time to apply a weed and feed product, with a second application in late spring or early summer. Follow up with a hearty dose of watering to allow the fertilizer to penetrate the soil. Scott's Bonus S variety of weed and feed offers the best protection against weeds and provides the most balanced nutrients.