Brooklyn Botanic Garden.

The idea of Forsythia Day was spurred by Mrs. Edward C. Blum to plant forsythias to enhance the beauty of Brooklyn. Brooklyn Borough president Cashmore proclaimed forsythia the official flower of Brooklyn in 1940. Forsythia Day is celebrated in April when the flowers blossom.

From the description of Forsythia Day collection, 1940-1980, 1940-1957 (bulk) (Unknown). WorldCat record id: 155451985

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