Verdone Extra Lawn Weedkiller 800ml The Verdone Extra Lawn Weedkiller ready to use gun is an easy to use lawn weed killer which kills many of the common lawn weeds & contains herbicides to give great control without harming the grass. The most common weeds that everyone wants to get rid of are the white clover blackmedick lesser trefoil daisy dandelion plantains & common mouse-ear. Verdone extra guns are ideal for spot treatment of small patches & can be used from April to September.