Contra Costa Centre, CA's Seasonal Mosquito Barrier Treatment Team

Residual barrier spray typically holds for around three weeks before new mosquito activity requires re-treatment.

Both — barrier spray handles adult mosquitoes while larvicide treats standing water we can't drain, addressing the full breeding cycle.

We use products labeled safe for treated areas once dry, and can discuss specific concerns about vegetable gardens or pet areas during scheduling.

Event treatment is common; we time the application so the barrier is at peak effectiveness for your specific date.

Standing water features require a different approach — larvicide — because barrier spray only affects adult mosquitoes, not developing larvae.

A three-week cycle is typical, though heavier rainfall seasons sometimes call for tighter scheduling. We recommend a quick yard check after heavy rain, since new standing water can appear in places that were dry all season.