Time of herbicide application - whether applied as pre-plant or pre-emergence or post-emergence

Type of weed

Climatic conditions

Concentration of spray material

Formulation of herbicides

Type of carrier used in herbicide formulation

Use of surfactants

Soil type

Type of sprayers and nozzles

Previous history of weeds

Herbicide mixture

All these factors should be considered while applying them to control unwanted herbs and to derive maximum benefits from the herbicides.