The methods and measures you take against weeds growing in your garden fall under four different categories.
These include mechanical or cultivation such as hand weeding or hand-pulling, cropping or cultural when you use seeds which are strong and of good adaptable variety or the ones which can quickly germinate, biological methods which include planting quick growing crops with consuming large leaf area and finally the chemical method that involves the use of pesticides and fungicides for weed control.
Each method has its qualities but a good farmer mainly uses any one of these methods or sometimes a combination of them to control weeds in the garden. In case there are just a few weeds in the garden then it would be wise to deal with them locally with simple methods like digging them out using a two-pronged fork.
However, if they are the rosette variety of weeds or the type which has long taproots then you can spot treat them with the help of selective weed killer.
This can be applied using an aerosol container or with a puffer pack. The other method would be injecting the weed killer into or o the leaves of the weed depending on the instructions given in the weed killer product. In case of a bad infestation of weeds in your garden, it might be necessary to treat your entire lawn.
After you have sprayed the weed killer on the plants, they are absorbed by the leaves into the sap and are ten circulated through the plant. Therefore the weed killer would be more effective when they are applied during late spring or during early summer when the plants grow fast.