Safer Brand Insect Killing Soap is a gentle, contact-killer spray made from Potassium Salts of Fatty Acids that effectively controls common soft-bodied garden pests like aphids, spider mites, whiteflies, and mealybugs by disrupting and dehydrating their protective outer shell.
 
Staggs Garden Center likely recommends it because it is an OMRI Listed® (organic) option that leaves no harmful residual effect, allowing gardeners to spray safely on vegetables, fruits, flowers, and houseplants right up until the day of harvest.