Notes
How bad are the mosquitoes in St. Johns County?
They are part of a marsh and summer-rain coast, especially at dawn and dusk from late spring through fall. A public mosquito-control district treats and monitors the county; you still drain standing water and wear repellent. After heavy rain or a storm, expect a worse week.
Last reviewed September 21, 2026.
If you are moving from a dry inland city, mosquitoes will be a character in your first summer. If you are moving from another Gulf or Atlantic county, you already know the plot. St. Johns is salt marsh, freshwater ditches, retention ponds, and a long warm season. That is excellent habitat.
The Anastasia Mosquito Control District of St. Johns County is the public agency that does surveillance, treatment, education, and research here. They publish service requests and fogging-style missions (weather permitting) and work with the county health department on advisories. Peak monitoring they have described in local news runs roughly May through November. Dawn and dusk are the hours officials keep repeating for West Nile-type risk and for ordinary misery.
Nuisance and disease are different conversations. Most weeks this is about sitting outside. Some weeks, after heavy rain, it is about staying covered. Local reporting has described animal West Nile detections and the usual public-health advice: repellent, screens, air-conditioning, long sleeves when you insist on twilight. Human cases have been uncommon in the stories officials tell about this county, but uncommon is not impossible. Follow current Florida Department of Health guidance rather than a paragraph written in September 2026.
Your lot matters. A screened porch changes the evening. A yard that holds water in toys and gutters invites a hatch. HOA ponds are pretty and they are habitat. After a named storm, expect a pulse. The district asks residents to request service when a pocket is bad; that is more useful than swearing at the sky.
Location still varies. A lot backing a preserve or a retention pond will feel different from a breezy dune street. Screens, a ceiling fan, and an early outdoor hour do more than a scented candle. Pets need the same dusk caution people do. After you move in, learn the district’s request number before the first bad week.
We would not skip this county because of mosquitoes, and we would not skip the DEET conversation with guests from Denver. Bring the habits. Then enjoy the marshes, which are the same ecosystem that makes the light so good. If you want the practical porch version, send a note.