I love the taste of Concord grapes. As a child, I remember eating grapes directly from the vines. TO me, there is no flavor comparison between concord grapes and store-bought grapes.
Concord grapes grown in central Illinois are quite different from most store-bought grapes. They are different types. Our native Concord and Niagara grapes are slip-skin types, which means that the skin easily slips away from the fruit pulp. Most store grapes are native to Europe and are called fixed skin varieties because the skin and pulp are all in one.
Here are some tips for harvesting the best grape. First, make sure your grapes are ripe before you harvest to assure that the grape is fully sweet.
A grape's color change is not always the best indication of ripeness. Most berries change from green to blue, red or white (depending on the cultivar) as they approach maturity. Many grape cultivars turn a ripe color before their flavor fully sweetens. When fully ripe, the natural bloom or whitish coating on the berries will become more noticeable. The color of the seeds changes from green to brown.
Second, consider the size and firmness of the berry before harvest. It's helpful to be familiar with your cultivar's characteristics, but most grapes should become slightly less firm to the touch.
Finally, the best way to tell if a grape is ripe is to taste it. Unlike some other fruits, grapes do not ripen further once cut from the vine. So, be sure the grapes are ready before you harvest.
Grapes don't require direct sunlight on the fruits to ripen and develop good color. Rather, it is the amount of light that reaches the plant's leaves that determines the quality of the fruit. The leaves create the sugars that move into the fruit.
Once you've decided to harvest, you can store the grapes for about eight weeks. Refrigerators are a good place to store grapes. A crisper with a damp towel over the top of the fruit is ideal.
If you have an abundance of grapes, try making them into jellies, jams, juice, or wine. My family especially likes grape pie. Grape pie is time-consuming to make, but worth every bite! I'll post my grape pie recipe on my ILRiverHort blog at go.illinois.edu/ILRiverHort.