Overseeding is the best way to fight weeds in your lawn. If your lawn is healthy, weeds will be crowded out and will have a harder time taking root. Overseeding is spreading grass seed over your existing lawn to make your current lawn thicker. If there is not a lot of top soil on your existing lawn, be sure to rake in good quality soil with the seed to ensure germination.
You can spread grass seed by hand or a spreader. If planting by hand, ensure to spread the seed evenly. A frequent mistake made with planting grass seed is planting it on thin topsoil. Lightly rake the soil surface to ensure good seed to soil contact after applying the seed. Avoid burying the seed too deeply. If seed is planted too deep, it may fail to emerge. A planting depth of 2mm (1/16 inches) is ideal.