A list of Chicago's farmers markets that get the MrBrownThumb Seal of Approval* and you should visit them now that the weather is cooperating. If you have a favorite I didn't include make a case for it in the comments and I'll add it.
Chicago Downtown Farmstand
66 E. Randolph Street
M-F 11AM-7PM Saturday 11AM-4PM
See my post Chicago Downtown Farmstand
Daley Plaza Farmers Market
50 W. Washington
Every Thursday 'til October 15th 7Am-3PM
Logan Square Farmers Market
N Milwaukee Ave & W Logan Blvd
Every Sunday from June 'til October. 10AM-3PM
Farmer Fridays @ Uncommon Ground
1401 W. Devon Ave. In the parking lot of restaurant & Organic Rooftop Farm
Every Friday 4PM-8PM
Lincoln Park Farmers Market
Armitage Ave. & Orchard St.
Every Saturday 'til October 31st. 7AM-2PM
61st Street Farmers Market
6100 S. Blackstone
Every Saturday 'til October 31st 9AM-2PM
Bronzeville Community Market
4400 S Cottage Grove
Every Saturday 'til October 31st. 8AM-1PM
City Farm Heirloom Tomato Stand
1204 N. Clybourn Ave.
Every Monday-Saturday 'til October 31st. M-F 3PM-6PM Sat 10AM-1PM
Pilsen Community Market
1800 S. Halsted
Every Sunday 'til September 27th. 9AM-2PM
Independence Park Farmers Market
Independence Park along Irving Park Rd
Every other Sunday 'til October 11th 9AM-1PM
The Chicago Botanic Garden Farmers' Market
First and third Sunday of the month. 9AM-2PM
Oak Park Farmers Market
460 Lake Street.
*There is no MrBrownThumb Seal of Approval--there isn't even a sticker, I just made it up. Want to read something funny? Check out the post on farmers markets on StuffWhitePeopleLike.com, it is hilarious, and then go to a farmers market and talk about Fast Food Nation or pick someone up-- don't forget to mention Food Inc. & Michael Pollan. I impressed (perhaps shocked is a better word) a couple of people during my visit to the organic rooftop farm when I knew about Food Inc. and who Michael Pollan was.