Mix 1 tbsp. of dishwashing liquid and 1 cup of cooking oil such as peanut oil, safflower oil or soybean oil. This is the stock solution that you have to dilute before using.
Pour the stock solution in a container and store it near your garden supplies.
Mix 1 to 1 1/2 tsp. of the stock solution with 1 cup of water and pour the mixture in a spray bottle before use.