How to Promote Grape Growth on Vines

Transplant small, manageable grapevines while dormant in late winter or early spring. Move them to an area where they will receive full sun. Grapevines need warm temperatures to encourage fruiting. Transplanting mature grapevines is not as practical, with their vast root systems and lengthy vines.

Prune out excessive growth and all canes one year old and over. Prune grapevines growing from their own roots, as well as rootstock, with hand-held pruning shears while they are still dormant. Grapes are produced on growth from the previous season, so pruning the vines encourages more growth for the next season. Leave four main canes, two on each side of the trunk. Also leave four short canes, or renewal spurs. Keep one or two buds on each renewal spur, which will provide the canes for the next year's harvest.

Determine the number of buds to keep on the remaining eight canes. Leaving too many buds results in lots of greenery and little or no fruit. If you remove 1 pound of canes, leave 30 buds. Leave an additional 10 buds for each additional pound removed after the first pass. Include both buds on the fruiting and renewal spurs in the equation.

Support the grapevines with wire or cable on strong vertical stakes. Stretch and secure the four long canes along the trellis wires with garden ties.

Trim back the tips of the four long canes in the summer. This prevents the vines from utilizing food otherwise needed for fruit development.

Encourage bees to visit the area where the grapevines are planted to promote pollination for fruit set. If there is a shortage of bees or pollination activity, the number of fertilized flowers will be greatly reduced. Unfertilized flowers will fall off the vine instead of fruiting. Plant a variety of flowering plants near the vines. If the grapevines grow in a vineyard, consider planting rose bushes at the ends of the rows. For organic weed control, consider planting flowering cover crops between the rows, such as mustard or clover.

Test the pH level of the soil with a soil-testing kit and apply a light fertilizer if needed. Do not over-fertilize or use a nitrogenous fertilizer. This may create vigorous vine growth but little fruit production.