How Do Farmers Harvest Grapes?

Types

• Grapes of the variety Vitis vinifera are native to Central Europe, the Mediterranean region and parts of southern Asia. This variety of grape is also becoming common in California and is now grown all over the world. These groups are grown as table grapes and for wine, raisins, juice and some preserves. Grapes native to eastern North America are from the group Vitis labrusca; Concord grapes are one of these types. This species of grape is used for sweet grape juice and jams and jellies.

Geography

• Grapes need full sun in order to ripen, so they are planted on southern-facing slopes. North-facing fields and low-lying areas generally stay colder longer, so grapes are not suitable for those areas.

Checking for Ripeness

• Grapes will not continue to ripen once taken from the vine the way some fruits will, so they must be fully mature before they are harvested. The most common method to determine if grapes are ripe is to taste them. The taste of the grape should be sweet and full. If it is still bitter, it is not yet ripe. The color and size of the grapes are also major indicators of ripeness. Although the color of the grapes changes when they mature, color alone is not always the best way to tell if a grape is ripe. When full size and at peak color, ripe grapes give a little to the touch. They should not be very hard.

Harvesting by Hand

• Grapes are harvested by hand using hand shears or a knife. Grape clusters are gently pulled away from the vine and clipped at the stem with the shears or knife. Some stem should be left for ease of handling. Grape clusters are then placed in a grape crate or other tray so that they are not stacked on top of one another.

Machine Picked

• Using a machine to pick grapes provides the farmer the ease of not having to harvest by hand and also the ability to harvest at night when temperatures are cooler. Grape-picking machines are generally used for juice or preserve grapes, not for grapes destined for the table or for wine. Although different machines will work in various ways, most machines shake the row of grapes they are riding over, which allows the grapes to fall onto conveyor belts. The grapes are then carried through to a chute that deposits them into a truck usually pulled by a tractor.