Organic Mechanics Pure Rice Hulls are used to deter annoying fungus gnats， as a perlite substitute， or as weed control in outdoor containers. To deter gnats and weeds， use the hulls as a mulch， keeping unwanted intruders away. Hulls are broken down into phosphorous and silica for your plants Contains approximately 8 quarts of rice hulls Perlite Substitute: Mix into soil to lighten a blend and increase porosity， air space， and drainage. Use 10% less Rice Hulls than you would with perlite! Fungus Gnat Deterrent: Make your plants a place they don't want to go: Add 0.5¿-0.75¿ to the top of your soil as a mulch Weed Control: Stop weeds from growing by adding 1.5¿-2.0¿ to the top of your soil as a mulch. Potting Soil Made in USA Your security is our number one concern