When do hummingbirds return from the south to north east IL.?

That will depend on a lot of factors.Weather being one.As far as I know there is no known specific time for these beauties to surface. All I can recommend is to plant as many plants as your space allows to attract them in your yard.

I live in the south, Louisiana. The hummingbirds are here. I always put my feeders out by March25th. They were earlier than that this year.

If you don't want to go the artificial hummingbird feeder route..then plant as many red blooming perennials as you can..a favourite of mine is a small Holland bulb called ? I will search my records and get back to you with that info..but what I love about this particular variety is they grow 2-3 feet tall..sway in the breeze, have deep tubular flowers which collect the dew and dew nectar is what the hummingbirds love..they are large enough to envelope the entire bird so they feed in complete safety..sometimes I miss them altogether and only see them descending and ascending but it gives me JOY that not only is the flower beautiful for me but sustenance for them....they flit around and cover a huge territory and seem to know what is blooming in what yard and they make the trek...you don't have to know anything..just grow anything red..they will also be attracted to other colours..but the feeders all come in red..and that is the reason..they are attracted to it first...have fun..keep you camera handy - you will be surprised at the many varieties....when I vacationed in Cuba the particular resort I was at was at was special...the birds came early in the morning, before we humans were knows to rise..the familiar buzz of their wings was the sign they were around...flying so fast you had to really be watching..there are so many distractions, all beautiful in Cuba..but being a gardener, and a perennial early riser...I got to see them..Roz