They don’t ship well, so are used mostly for processing into juice, jams and jellies.
They can be hard to process at home. They have tough skins, and many large seeds inside, which cling to the pulp. The stems also cling to the grapes: if you pull one off a bunch, the stem will come with the grape.
Though Concord Grapes are slightly sweet, they produce a wine that is as tart as sucking on a lemon. To compensate, wine makers have to ladle sugar by the barrelful into the wine. This is why wines made from these grapes are always very sweet.
Jewish Kosher wine used to be made entirely from these grapes. One or two brands still are.
Concord Grapes ripen early. This made them popular in the Northern US and in Canada, as they were ready to harvest before the fall frosts.
History Notes
The Concord Grape was developed in 1849 by Wales Bull, and introduced commercially in 1854 in Concord, Massachusetts. It was named after that town. The first commercial juice was grape juice made from concord grapes in 1869. Concord Grapes began losing their popularity after Konstantin Frank proved that European grape vines could survive North American winters (see under History in main Grape entry.)