PROBLEM TO BE SOLVED: To provide a weed control method in a farm land without agrochemicals, and to provide a farming method using the same.SOLUTION: A farming method performing weed control comprises steps of: diluting a natural resin containing a rosin acid as a main constituent obtained by distillating colophony which is a sap of a plant belonging to Pinaceae, with water; pouring the diluted natural resin into a paddy field after rice planting; and leaving as it is till white or yellow powder appears in the paddy field. A salt produced by neutralizing rosin composition which is liquid at ambient temperature and inhomogeneous, by using alkali, can be preferably used in the farming method. And also an aqueous alkali soap solution which is a mixture of a rosin liquid at ambient temperature and inhomogeneous and aliphatic acid can be preferably used.
