CHICAGO (WBBM) – The farmers market openings on the downtown Daley and Federal plazas have been delayed until late May because of this weekends NATO summit.

This year’s unusual weather also means you may not find your favorite item at your neighborhood farmers market this year.

The owner of a Michigan orchard that sells to seven Chicago area farmers markets tells the Sun-Times that mother nature has not cooperated.

Last March was the warmest on record in the Midwest which made it hard for farmers to guess when the last hard frost would be so it’s safe to plant.

The recently updated Plant Hardiness Zone map shows an average 5 degree warm up and already puts the last frost date earlier. It means some produce may have grown and been harvested before most markets open or put on sale earlier than expected. Chives were so early, some had to be mowed down and regrown. Cherries could be early this year and there’s concern grapes and apricots were damaged. One farmer says it’s the first year he’s ever planted corn in March.