James from Crowley writes
Onslaught FastCap as well as many other liquid insecticides only need about 30 minutes to dry. Once dry, they can hold up to rain rather well. However, it is much easier for the product to bond to porous surfaces like concrete and siding then grass and your lawn. You may want to apply again just to be safe when there is not rain in the forecast for at least 24 hours
Answer last updated on: 07/10/2014