How long does it last before having to reapply?

When to reapply Ortho BugClear Insect Killer for Lawns will depend on where it is being used. On Roses, Flowers, Shrubs & Small Trees allow 7 to 14 days between each application. Hard to control insects may require 2 to 3 applications. Around House Foundations, Porches, Patios, & Stored Lumber (Do not treat firewood.), repeat application every 14 days if necessary. On lawns, wait 4 to 6 weeks between applications.