In most cases, private property owners can keep up yard signs year round. With that said, there are some communities where there are limits on when a homeowner can put up election signs in their yard.
So who do you contact to find out? Unlike yard signs along the right of way on most major roads, where the state Department of Transportation has jurisdiction, you will want to speak with your local government.
In smaller communities your best contact is usually the office administrative assistant, maintenance crews, code enforcement and in some cases the local police force.
In metropolitan locales, there is often a transportation department but if not code enforcement should be able to tell you if there are local ordinances that limit the amount of time that you can display a political yard sign.