wintering over

I'm just wondering when I should winter my trees? I'm in Wisconsin. Thanks

When they need it. I generally bring tropicals and subtropicals in when the temps drop below 40F (5C) at night. I keep things from a Mediterranean climate out until the they see a very light frost. The hardy stuff gets to see some fairly solid frosts to about 25F (-4C) so the deciduous trees lose their leaves. The really hardy stuff just goes on the ground and gets to see our coldest weather (-10F = -23C). Occasionally I get caught by a quick, cold snap into the low teens F and scramble to get things inside, on the ground, and am out spraying it all down with water at 2 am to coat it with ice.