When young seedlings are dipped into the clay solution,( dip all the way to the soil, including stems), they can not be found by pests as the clay disguises the plant’s unique scent. It also protects young seedlings from damage by insects that may try to eat or lay eggs in the stems, such as borers, cutworms, and even rolly pollies. If an insect pest does happen to find the plant, the fine clay is very irritating to them. It gets under the scales of insects and caused them to groom obsessively. They stop feeding and mating. 

As the new leaves start to appear, the plant has had a chance to establish and hopefully been missed by any pests. 

As the plants grow, they should be sprayed twice a month to keep all foliage and fruit inhospitable to pest insects. Both sides of the leaves should be sprayed, in squash, the underside is particularly important. 

The USDA)has conducted studies showing that kaolin is also effective in preventing thrips infestation on small fruit trees such as apples and peaches.

 An application of the powder applied at 50% bloom deters thrips. The use of kaolin clay at this point in fruit development helps more fruit to set and does not negatively affect the quality of the fruit. Kaolin clay will not harm beneficial pollinators.