Herbicide is usually a concentrate of potent chemicals to kill the weeds in the vegetation area of your house. The frequently asked question of the users of herbicides is how long does it take for weed killer to work? They are afraid if the useful plants could not survive after the spray then what to do? Some want to know whether the herbicide is that much strong to kill the desired weeds or not?
Also see: How Does Weed Killer Work?
There are several factors on which the weed killer works. The first factor is climate. If you are spraying the herbicide on the plants in a moist or cold atmosphere, it will work slowly. It can also damage the nearby vegetation. When you first time spray it to the plants, it should be a warm summer day.
The roots and leaves of the plant will absorb the weed killer quicker and then remaining concentrate will evaporate in the air. It will not harm the nearby plants. The spray in a hot summer day will work efficiently. Within the next 48 hours, the weeds will start turning into yellow color. Within a week or two these unwanted plants will die eventually.
Also see: How to Make Homemade Weed Killer
The next factor is the grass killer potency. If it contains the high potency chemicals, you will see it showing the positive results within a few days. If the concentrate is not so potent, it may take one month to show its effects. In the first two to three days, they will begin twisting. It shows that the herbicide is affecting the plant. Now within two weeks the natural green color of the plants will start fading. Within a few more days, it will die.
Try to spray sufficient amount on the roots and leaves. If the roots absorb the concentrate, they will start dying. Make sure the roots are not getting fresh again. If it refreshes, you will see it getting strength again. If you are using a weed killer gel instead of solution, it will stick to the unwanted plants. Within 24 hours, you will see them turning to brown and eventually die within 48 hours.
Must see this guide to dispose of weed killer.