Caring for grape vines requires relentless pruning of the canes. Grape vines are hardy plants, they more pruning they receive, the more vigorous the plant becomes, and a better harvest is produced. It is crucial for the root structure of the vine to be sturdily developed before allowing it to produce fruit. Proper root development can take up to two years before the vine can adequately support the weight of the fruit it bears.
Healthy, robust vines require full sunlight, well drained soil and trellis-like support to allow the vines to grow upright, effectively keeping insects and diseases at a minimum. Weeds compete aggressively for water and nutrients, so a systematic weeding system is necessary. Grape vines are extremely sensitive to chemical weed killers, so weeding should be done by hand or using a mechanical device.
Though watering of the vines is essential when the vines are just planted, over watering should be avoided at all costs. In fact, once the vines are established and thriving they don't require much water at all, and sporadic mulching will be sufficient to keep the roots cool and moist during the days.
Reduce over-production of grapes by thinning the blossom clusters that look misshapen. Over-production of fruit is not good for the vine and it will result in lower quality fruit.