Are you talking about feeders for hummers or for other birds? I'm not talking about hummers.
Here, we start to put out feeders by the middle of Fall. That way birds know they are there to help get them through the winter. It is suggested that we leave feeders out here year around with just a little food in them so birds become familiar with where there are potential sources of winter food.
I have finch socks, suet baskets, long wire feeder full of black oil sunflower for the birds that like to feed while clinging. I also have several feeders for the birds that prefer to perch while feeding.
I throw out seed for my ground feeders like the doves.