Try this... 4 cups (1 Litre) of white vinegar 1/4 cup (50 ml) of table salt 2 tsp (10 ml) of your favorite liquid dish soap. Put this mixture into a spray bottle and spray it on your weeds when it is hot out. Be careful not to spray it on any desirable plants since it doesn't "know" the difference and you can wave good-by to them as well...