- Georgia Grape Horticultural Areas
- Best Place to Plant
- Purchasing Plants
- Planting the Vine and Plant Spacing
- Trellis Systems and Trellis Construction
- Pruning the Bearing Vine
- Cultivation and Weed Control
- Insects and Diseases
- Mountain Area
- Upper Piedmont Area
- Lower Piedmont, Middle and South Georgia Area
Three primary species of bunch grapes are grown in the United States the European bunch grape (Vitis vinifera), the American bunch grape (Vitis labrusca) and the Summer grape (Vitis aestivalis). Bunch grapes are often called “pod” grapes in rural Georgia since they produce large clusters of fruit. Georgia's climate is not well-suited to home garden production of European bunch grapes, but American bunch grapes and hybrids between the two species (French hybrids) grow well in Georgia. If grapes are well cared for and sprayed when diseases and insects threaten, you can expect yields of 20 to 30 pounds of fruit per vine. The Summer grape is also an American species and is represented by a few varieties good for wine production. If you want to grow European bunch grapes, consult www.smallfruits.org for the Mid-Atlantic Wine Grape Growers Guide. This is also a good source for more detailed information on growing French hybrid grapes. The spray program to produce good quality European bunch grapes is intensive and generally impractical for home gardeners.
Pierce's Disease is a bacterial disease spread by leaf-hopper insects that kills susceptible bunch grape varieties. It is very common in middle and south Georgia. Pierce's Disease has not been a significant problem in areas of Georgia above 1,300 feet elevation (high mountain area). Between 1,000 and 1,300 feet (upper Piedmont area), disease pressure varies greatly from site to site, but home garden plantings of Pierce's Disease susceptible bunch grapes are generally feasible. Between 700-1,000 feet in elevation, Pierce's Disease will often destroy the vines of susceptible cultivars within 5 years. Below 700 feet elevation, Pierce's Disease often destroys the vineyard within 3 years. These boundaries can shift with climate variation from year to year. Below 1,000 feet elevation it is recommended that primarily Pierce's Disease resistant cultivars be planted.
In the Mountain and Piedmont areas of Georgia, late spring frosts can reduce yields significantly, so plant bunch grapes on elevated sites if possible. In all areas, avoid low spots where cold air settles. The site should be in full sun most or all of the day. Well-drained, loamy sand, sandy loam, loam or clay loam soils are best for grape production. Avoid areas where water stands after heavy rains.
American type bunch grapes and Summer grapes are usually grown on their own roots in North Georgia. European grapes and French hybrids are usually grafted on rootstocks such as SO4 or 3309 to provide increased Phylloxera resistance. On sandy sites (especially in South Georgia), test for the presence of root knot nematodes. If they are present, grapes should be grafted on nematode resistant rootstocks such as 'Tampa,' 'Florilush' or 'Dog Ridge.' Low vigor varieties are often grafted to improve their vigor, this noted in the tables.
Many varieties of American type bunch grapes will perform well in Areas 1 and 2 in Georgia. Also, certain selections of French Hybrid grapes (wine grapes) are suggested for trial in these areas. Several hybrid bunch grapes are worthy of trial in Area 3 of Georgia. (See tables 1 and 2.)
|Table 1. Varieties for the Upper Piedmont and Mountains in Approximate Order of Ripening|
|Variety||Type||Areas of Georgia||Red Wine||White Wine||Juice Jelly||Fresh Eating||Comments|
|Venus||A||1 & 2||X||X||seedless, blue-black fruit; seed traces present|
|Interlaken||F||1 & 2||X||seedless; suffers cold damage often|
|Foch (Kuhlman)||F||1||X||blue-black fruit|
|Aurora||F||1||X||X||good wine; fresh eating|
|Jupiter||A||1 & 2||X||seedless, blue fruit|
|Reliance||A||1 & 2||X||seedless, red fruit; fruit cracking problems|
|Cascade||F||1 & 2||X||X||performed well in Georgia test|
|Van Buren||A||1||X||X||black fruit|
|Alwood||A||1 & 2||X||X||blue fruit|
|Ontario||A||1||X||green to amber fruit|
|Fredonia*||A||1 & 2||X||X||blue fruit|
|Baco Noir (Baco #1)||F||1 & 2||X||blue-black fruit|
|Delaware* †||A||1 & 2||X||X||X||reddish fruit, small but sweet; good red wine|
|Chelois||F||1 & 2||X||blue-black fruit|
|Norton (Cythiana)* 56AF||A||1 & 2||X||V. aestivalis variety; good quality wine; probably has some Pierce's Disease resistance|
|Chambourcin||F||1 & 2||X||good quality red wine|
|Mars*||A||1 & 2||X||seedless, blue fruit|
|Saturn||A||1 & 2||X||seedless, red fruit|
|Chancellor||F||1 & 2||X||dark red fruit|
|Buffalo||A||1 & 2||X||X||good yields|
|Niagara* †||A||1 & 2||X||X||golden fruit|
|Cayuga White||A||1 & 2||X||vigorous vine|
|Concord||A||1||X||X||X||blue fruit, ripens unevenly; not recommended|
|Sunbelt*||A||1 & 2||X||X||Corcord type but ripens more evenly than Concord|
|Neptune||A||1 & 2||X||white seedless|
|Portland †||A||1 & 2||X||X||amber fruit|
|Champagne||A||1 & 2||X||X||reddish fruit|
|Catawba †||A||1 & 2||X||X||X||purplish red fruit, uneven ripening|
|Vidal||F||1 & 2||X||yellow fruit|
|Golden Muscat||F||1||X||X||greenish-amber fruit|
|Villard Blac*||F||1 & 2||X||greenish-yellow fruit; probably has some Pierce's Disease resistance|
|Seyval*||F||1 & 2||X||yellow-white fruit|
|* = Most outstanding varieties.
Type: F = French hybrid (new shoots grow upward; use low trellis — 3 ft. — with catch wires); A = American type (new shoots grow down; use high trellis — 5 ft.)
† Should be grafted on Dog Ridge or similar rootstock for best results
|Table 2. Bunch Grape Varieties for Middle and South Georgia in Approximate Order of Ripening (all are American types)|
|Variety||Red Wine||White Wine||Juice Jelly||Fresh Eating||Comments|
|Blanc Dubois||X||X||good white wine|
|Orlando seedless||X||small, greenish-yellow fruit|
|Suwanee*||X||X||good eaten fresh and as wine|
|Stover †||X||X||good, golden fruit|
|Blue Lake||X||X||purple fruit|
|Midsouth||X||sour, purple fruit|
|Miss Blue||X||sour, purple fruit|
|Conquistador* †||X||X||X||very good, similar to Concord|
|Lake Emerald||X||X||greenish fruit|
|Black Spanish (Lenoir)||X||dark purple fruit|
|Daytona †||X||low yield but good eating; pink fruit|
|* Most outstanding varieties
† Graft on Tampa, Lake Emerald, Florilush or Dog Ridge rootstock
Varieties Suggested for Home Garden Trials in Area 3 in Georgia
Several hybrid bunch grape varieties have been developed which are worthy of trial plantings in middle and south Georgia. All of these have good resistance to Pierce's Disease, the primary limiting factor to bunch grape culture in the middle and southern portion of Georgia. Table 2 lists suggested varieties for home plantings.
Bunch grapes, unlike muscadines, do not require cross-pollination, so it is not necessary to buy two or more varieties for pollination. You may, however, want several varieties to extend the fruiting season.
Most bunch grapes are sold as 1-year-old or 2-year-old plants. Generally, the 2-year-old plants grow off better and are worth the small extra investment. Be sure to purchase them from a reliable source.
It is easiest to construct the trellis before planting, but it can be done after planting. Since most bunch grapes are somewhat less vigorous than the native muscadine grape, only 8 to 10 feet of row will be required for each vine. Lay off the rows at least 10 feet apart (12 feet on hilly land). Use straight rows for level or slightly rolling land and contour rows for hilly terrain. Prior to setting the vines, soil test and adjust the soil pH to 6.0 to 6.5 with dolomitic limestone. Most Georgia soils are low in magnesium, thus the need for dolomitic limestone.
To plant, prepare a hole large enough to accommodate the entire root system in its natural spread. Set the plant at or slightly below the level it grew in the nursery. Fill the hole with the natural topsoil and firm it. Do not place fertilizer in the hole. (See section on fertilization.) After firming the soil, water liberally.
Following planting, cut the vine back to a single stem with two to three good buds remaining. After growth begins, select the main trunk of the vine from the stronger of these shoots.
Normally number 9 wire is used for grape trellis construction. All posts should be pressure treated or made of termite/rot resistant wood such as heart of cedar.
American Type Bunch Grapes
American type bunch grapes are vigorous and have a trailing, downward growth habit. Three high trellis systems are commonly used to train home garden American type bunch grapes in the south: the double curtain (two wire horizontal system), the two wire vertical and the single wire. The top wire is typically 5 feet to 5½ feet above ground level in all three systems.
The Double Curtain Trellis — This trellis system is usually the most desirable of the three systems because of increased yields. The trellis system has two wires 4 feet apart and 5½ feet above the ground. Figures 1 and 2 show details of how to construct the double curtain trellis. A simple T-bar trellis constructed from treated 4" x 4" posts can also be used.
The Two Wire Vertical Trellis — The two wire vertical trellis used for the four-arm Kniffin training system is considerably less expensive to construct than the double curtain trellis. However, shading of the foliage on the lower fruiting canes by the upper canes reduces the quality and productivity of the grapes on the lower wire. Figure 3 illustrates the construction of the two-wire vertical trellis. The primary use for this trellis is in situations where space is limited, but where there is good direct sun exposure. If direct sun exposure is limited, use the double curtain or single wire trellis.
Single Wire High Trellis — This trellis is recommended where diseases are a problem. The vines dry off more rapidly after a rain on the single wire. Space the vines 10 feet apart when using this trellis. Yields are lower than the other two systems, but construction is easy. Construct end supports as shown in Figure 3.
French Hybrid and European Bunch Grapes
Single Wire Low Trellis with Catch Wires (AKA Low Trellis Cordon System) — French hybrid and European bunch grapes have new shoots that naturally grow upward. Two removable catch wires above the cordons (arms) further encourage this growth habit and allow good exposure of the fruit to sunlight and fungicide sprays. The low-trellis cordon system establishes the cordons 3 to 3.5 feet above the ground and includes two removable catch wires positioned at 10 inch intervals above the cordon wire. This system promotes vertical growth, resulting in a narrow, upright vertical canopy. (Figure 4).
Training Young Vines
First Year — Regardless of the training system to be followed, your goal is the development and establishment of a well develop root system. It is recommended that after planting, the strongest cane be cut back to two or three strong buds. Remove any other canes present. Because it is sometimes difficult to determine the condition of a dormant vine, however, some growers prefer to leave five to six buds and then, when growth starts, only allow the most vigorous or desirable buds to develop into shoots.
If the trellis cannot be constructed the first growing season, then a stake 4 to 5 feet high should be driven in the soil near each vine and the new growth trained to it. Tie the shoots loosely, or with plastic tape, to avoid the possibility of girdling. In cool areas of the country, growth rates are slow and vines are often pruned back to near ground level the first winter to help develop a vigorous trunk the second year. In Georgia the growing season is long and vines often make impressive growth the first year.
Double Curtain — Develop a double trunk (Y shape) for each vine approximately 30 inches above the ground. This is done by pinching out the growing point and forcing two shoots to develop. One trunk should be allowed to grow to one of the trellis wires and the other trunk to the other wire. Just below the wire, pinch out the tip of the growing shoots to encourage side branches. Under good conditions, the trunk system for the grape vine should be developed by the end of the first growing season.
Two Wire Vertical Trellis — Develop a single strong shoot arising from the young plant by removing competing shoots. Train this shoot to a string or stake running from the upper wire of the trellis to the ground. Just below each wire pinch out the tip to encourage two side arms to develop.