When Are Concord Grapes Ripe?

Concord grapes belong to the European family of purple grapes

While not usually sold for table consumption, Concord grapes are grown for their use in juices, jellies and jams. According to the website ConcordGrape.org, October is often the peak ripening month for U.S. Concord grape harvesting.

Background

Concord grapes, unlike other grapes of the purple European variety, are known for their loose skins and seeds and are native to North America. Concord grape vines are often grown by commercial harvesters, but consumers may purchase concord cuttings from local nurseries for home planting.

Ripening Characteristics

The Purdue University Consumer Horticulture website states that grapes, including the Concord variety, are ripe and ready for harvesting when their shade turns from green to blue, their seeds develop in color from green to brown, their exterior coating has a whitish tint, and their feel is slightly firm. Taste can also be used to determine ripeness, as the grape will be sweeter when more ripe.

Uneven Ripening

Caused by hot weather growing conditions and seen in Concord grape harvesting, uneven ripening occurs during some harvesting seasons. If this happens, only half of your Concord grape harvest will be edible, while other grapes in the same cluster will be fully-formed and green, but not sweet.

References

• Purdue University Consumer Horticulture: Harvesting Grapes

Resources

• Concord Grape Growing
• Concord MA: Cooking with Concord Grapes
• Grape Science: Concord Grapes and Health