You'll find great strawberries at Sycamore, Samascott, and others.
Samascott has asparagus as well as scapes and many stands have sugar snaps and shelling peas. Sycamore, Bodhitree, and Stokes have beautiful basil and Oak Grove, Binder, and others have excellent herb sets. Oak Grove has lush pepper plant and tomato plant varieties. Bodhitree has shishito peppers, agretti, and other unique produce.
Berried Treasures has small potatoes, scapes, cress, and other interesting produce as well as beautiful peonies. Dutchmill has lovely country flowers and lilies.
To see these and other stands and produce:
Union Square Greenmarket June 21