This image shows a portion of the flowers on display within the conservatory at Garfield Park in Chicago, Illinois during the Christmas Flower Show.
The description states:
CHRISTMAS FLOWER SHOW
The Annual Christmas Flower Show of the Chicago Park District in Garfield and Lincoln Park Conservatories features more than 10,000 seasonal blooms. This is a view of the Garfield Park exhibit.
–It appears from online sources that the Garfield portion of the show has been discontinued and the show is held along with others at the Lincoln Park Conservatory alone. The card likely dates from the 1950s.