Weed control applications usually cost around $100 each for a standard-size yard, and most professionals charge between $30 and $60 per hour for manual weed removal. Your total is affected most by the size of the weeded area. Some weed service companies offer weed control treatments, selective herbicide spraying, and manual removal and upkeep as part of a package, costing around $600 annually. You might pay less if you hire the same company for other lawn services, like flower bed upkeep, aeration, overseeding, and pesticide application.

The best way to prevent weeds is to use polymeric sand, which hardens and blocks weed growth when activated with water. If you're using regular sand, you'll need to refill and compact it more often. Keeping the surface clean and free of debris can also help prevent weed seeds from settling in the joints.

It usually takes between two weeks and a month for weeds to fully die off after you spray them with herbicide, but they will start to wilt within the first week. Different weed sprays produce different results, with some working more quickly and effectively than others. Similarly, some weeds are killed more easily than others. Consult your weed removal pro for an exact timeline based on their weed removal method.

There are organic herbicide options that will kill grass but not flowers, including white vinegar or a dish soap solution. Commercial selective herbicides can also target grass over other plants, but read the instructions carefully to avoid damaging your garden. Herbicides that kill grass but not flowers usually include ingredients like clethodim and sethoxydim. Otherwise, your best bet will be to weed by hand.