Grape vines grow vigorously throughout North America and have grown wild for hundreds of years. Newer varieties of grapes, however, often are hybrids, which means that their seeds won't grow true, or may not even have seeds. Propagating grape vines from dormant cuttings is the easiest and most reliable method of growing new vines.
Cut stem sections from one-year-old growth on an existing grape vine. Each section should be approximately 6 inches long and contain three to four leaf nodes. Make the cuts on a 45-degree angle to the stem. It is not necessary to include the vine end with the cuttings. Remove any existing leaves.
Fill the planting pots three-fourths of the way with the potting medium. Soak thoroughly with water until all of the medium is saturated.
Dip the bottom cuts of each grape vine cutting into the rooting medium and tap off the excess. You will be able to tell which end is the bottom by holding the cutting straight up and down. When it is the correct direction, the bud nodes will face upward.
Plant the cuttings into the pots, two to a pot. Sink the bottom end into the soil 2 inches and press the soil gently around the base of the cutting. Water again.
Place the soda pop bottle over the cuttings in each pot, ensuring that the caps are off. The bottle will keep the cuttings moist while they are developing new roots.
Water the cuttings daily until roots begin to form at about four to five weeks. Remove the cover when you see new growth starting in the cutting, signaling the formation of roots. Plant the cuttings outdoors in the spring when all chance of frost has passed.