Posted by Brent Wilson on 8/30/2016 to Fruit Gardening
When growing grapes the vines should have some sort of support, but it's not necessary to build an elaborate system that vineyards use. Support is optional the first summer, but essential after that.
Here are several different ways the home gardener can grow grape vines...
Growing Grape Vines In A Fence
Space grape vines 6 to 10 feet apart along a fence. Plant your young grapevine to grow against the fence and allow it to grow to the top of the fence (usually 4 to 6 feet).
During the first dormant season after planting, or when your vine(s) have grown to the top of the fence, in January or February select one shoot that will serve as the main trunk, and cut any others off at ground level.
During the second growing season allow vines to grow naturally. Select 2 branches growing near the top of the vine to train along the top of the fence: one to grow right and one to grow left. If you want, you can attach a wire that will be about 30 inches above the ground and train two branches growing from the trunk to grow along this lower wire: one to grow right, one to grow left.
Tip: Remove fruit clusters during the second growing season so that energy will be spent into growing strong roots and a trunk.
The second winter, prune back the side canes along the horizontal-growing vines to a point they have about 10 buds on each. The next year they will grow shoots from these buds that will fruit. Select four other shoots close to the side canes and prune these back to two buds on each. These will be renewal spurs for the following year's production.
The third winter prune back the side canes that fruited to the trunk and prune back the renewal spurs to ten buds and select four more renewal spurs for the following year's fruit. Continue this process each winter. You should be removing up to 70% of the grape canes each winter and have lots of fruit!
Growing Grapes On An Arbor
First, you'll need a sturdy arbor, pergola or other structure that will be strong enough to hold the weight of the vines when mature. The posts should be a minimum of 4-inch by 4-inch. The top can be constructed of 2-inch by 2-inch lumber and topped with 1-inch by 2-inch lumber for the lattice work the vines will grow on.
Grow the grapes, one per post, selecting the strongest cane. Allow it to grow to the top of the post the first year, securing it to the post as it grows.
The first winter top the cane and allow it to grow side branches along the top of the arbor. If you let the vines just continue to grow, they will produce dense shade, but little fruit. So, if you want lots of fruit, you'll need to prune the grapes each winter by removing those canes that fruited the previous year, cutting back one-year-old canes to five to six buds, and leaving some renewal canes pruned back to two to three buds. The goal is to have canes on the trellis spaced 2 to 3 feet apart. Remove any weak, thin canes. You want to leave enough fruiting canes on the trellis to fill it back in each summer, but not so many that is becomes a tangled mess.
Growing Grapes On A Post
If you are low on free space, try growing grapes on a stake. Pound in a sturdy stake next to the grape vine and securely attach it. Let the vine grow to the top of the stake the first year then top it. Allow 4 to 5 side canes to grow. Remove all the rest.
Pruning Grape Vines
When to Prune Grapes
Pruning of grapevines is best done during the later winter, before buds along the branches begin to swell. The pruning cuts you make will most likely drip sap from their wounds until the plant breaks dormancy in the spring. This weeping is not harmful in any way to the plant. Sap in plants is not limited in supply like blood is for animals. It is primarily composed of water which is continually supplied by the roots.
The key to pruning grapes is understanding their fruiting habit. Grapes produce the most fruit on shoots growing off of 1-year old canes. If you have too many old canes (from no pruning), then you’ll get fewer grapes. If you prune back your vines completely each year, then you get lots of new growth, but again, few grapes.
The first winter, cut back the side canes growing out from the main vines to three buds on each. These will send out shoots that will produce grapes the next year. Remove all weak and spindly growth, especially along the lower parts of the trunk.
The second winter, prune back the healthiest canes to ten buds, select two canes as renewal spurs and prune those back to four buds on each, and remove all other canes.
Repeat this pruning each winter. Your trunk should be able to support four to seven fruiting canes each year as it gets older.
Other Grape Vine Pruning Tips
When doing your pruning in late winter it's best to remove any and all twiggy growth growing from the main trunk or the main canes.
Remove fruit during the first growing season or two to develop a strong root system and trunk.
Always use a sharp pair of bypass hand pruners or lopping pruners.
Purchase and plant only high-quality grape vines. I suggest container-grown plants in a 1-gallon container or larger.