Grape plants are easy to grow in a home garden, and they go through standard growth stages each year. Once planted, grapes take two to three years to produce vines and healthy vegetation. Beyond that, they'll produce tasty fruit each season for many years to come.
In the United States, new buds will form on grapevines in early spring. These buds generally appear sometime in March or April for most regions, when daily temperatures reach about 50 degrees F. These new buds swell and produce shoots, which will then produce new leaf growth. Shoots can grow up to 1 inch a day in warm climates, but they are fragile and vulnerable to frost damage in cooler climates.
Once daytime temperatures are in the range of 59 to 69 degrees Fahrenheit, flowers will appear in small clusters at the tip of the young shoots. Full flowers appear a few weeks after the first clusters; the pollination of these flowers produces the grape berry seeds. Most grapevines are self-pollinating, with a little help from wind and insects.
Fruit develops quickly after the full flowers have emerged and pollinated. Not all flowers will pollinate and produce fruit, so you may also see flowers falling from the vine during this stage of growth. High temperatures and not enough water can cause a reduction in fruit production for grapevines, as can the health of the vine itself. Generally 30 percent of grapevine flowers produce fruit on average, but this can increase to as much as 60 percent with the right growing conditions.
Once the initial fruit has set on the grapevine, it will take about 40 to 50 days to fully ripen. During the ripening stage, grapes go from being hard to soft. They'll also slowly develop their final coloring during ripening, though not all will change color at the same time.
Grapevines go dormant in winter, when they have no leaves, buds, flowers or fruit. The wood is twisted and gnarled, making for an interesting ornamental addition to the garden. Prune grapevines during the dormancy period so they'll produce larger amounts of fruit when the next season starts. Grapevines are generally pruned to just four primary canes--branches or arms--that produce new shoots and fruits the following year.