If you have the little no seeums biting bastards in your yard, you can treat it once a year and you should be good.
Now is a good time before it warms up.
This is the first year I have ever seen no see-ums in TX! And guess what they carry: (now) leischmaniasis. I saw dozens of cases in Brazil, but never in the US - but it is in fact here and not talked about. It's been treated like Lyme disease was. NPR says it is in fact here, but it's because of climate change, not the illegal aliens...