Warning:

The information contained in these web pages has not been verified for correctness. Some of the information contained herein is hearsay and may not be correct. Use the information from these pages only at your own risk!


Grapes

With newer, hardier varieties of grapes developed each year, more people are growing grapes in the home garden or in small scale plantings. Newer, seedless grape varieties that should do well in Massachusetts are now available.


Varieties

Varieties of red, blue, and white grapes are adapted to many areas of Massachusetts, some for fresh fruit, others suitable for wines. The limiting factor in grape-growing is our relatively short growing season and corresponding low degree-day heat units.

Recommended seedless varieties include:

Other recommended varieties include:

Refer also to recommended variety lists for Massachusetts available from your local county Cooperative Extension office.


Soil Preparation

Grapes prefer deep, well-drained, sandy, or gravelly loam soils. Excessively wet or dry soils should be avoided. Adequate soil preparation is essential since grapes are deep-rooted, long-lived plants. Work soil to remove perennial weeds, and add humus (peat moss, compost, aged manure) to improve soil quality.

Select sites with full sunlight and good air drainage--preferably a hill side that faces south. Frost-free sites are essential.


Lime and Fertilizer Requirements

Before Planting: Grapes prefer acid soils with a pH between 5.0 and 5.5. Thoroughly work in sulfur or ammonium sulfate (or similar material) as suggested by soil test results before planting. Well-aged manure at two to five bushels per 100 square feet can also be worked into the soil before planting.

After Vines are Planted: Commercial fertilizers are generally not necessary the year vines have been planted. Four to six ounces of 5-10-10 may be applied to poorly-growing, newly planted vines.

When Vines are Bearing: Each year, double the rate listed above until plants reach maturity. Three to four pounds of 5-10-10 (or equivalent) per vine per year is the recommended rate for mature vines.


Planting

Plant vines eight feet apart in rows that are eight to ten feet apart. Rows should run at right angles to the slope. In an area that normally is very windy, plant in the direction of the wind to minimize damage.

Purchase one or two-year-old vines. First grade, one-year-old vines are preferable. Vines should be planted at about the depth they were grown in the nursery. Grafted vines should be planted with the graft union about two inches above ground level. Roots should be spread out in the planting hole. After the vine is planted, remove all but the most vigorous cane, and cut back this cane to one or two buds.


Mulching

Mulching an area about two feet wide with grass clippings, straw, or other suitable material will help keep young vines free from competing weeds and will also help to conserve soil moisture.


Weed Control

Removing perennial weeds from planting sites and keeping growing vines free of competing weeds are essential aspects of grape growing. Mulching is a valuable way to eliminate many problem weeds.


Pruning and Training

The spring after planting, remove all but the most vigorous cane on each vine. Cut back the remaining cane to a height of between three and four feet. If the vine did not make sufficient growth the year it was planted, cut the vine back to two buds and treat it as a newly-planted vine.

The second year, trellis or stake the vine. If a trellis system is used, end posts should be eight to nine feet long and four to six inches in diameter. Set end posts three feet into the ground. Trellis wiring can be No. 9 or No. 10 galvanized wire or newer nylon-type lines.

There are many different systems for training and pruning grapes, depending on types of grapes planted and available space. For additional information, contact the Cooperative Extension office in your county.

Pruning is one of the most important cultural operations in grape production because it regulates both vegetative growth and fruit production.

To properly prune a vine, you should know something about its growth and fruiting habit. The vines should be pruned during the dormant season, preferably in March. Some things you must keep in mind are:

Prune the vine so you will maintain a balance between vegetative growth and fruit productions. Where a vine is underpruned, (too many buds left) the vine will produce many small clusters of small grapes that may fail to ripen properly. If the vine is overpruned, (too few buds left) the yield will be low and the vegetative growth excessive. To "balance prune" a vine, the number or buds left is adjusted according to the amount of one-year-old wood removed in pruning.

The following is a procedure you can use for balance pruning a vine:

Suggested pruning severity for balanced pruning of mature vigorous vines of some major varieties.

Varieties Nodes/first Pound Nodes/each add'l pound Maximum Nodes to Retain
Concord 30 10 60
Fredonia 40 10 70
Niagara 25 10 60
Delaware 25 10 60
Catawba 25 10 60
Foch 20 10 50
Leon Millet 20 10 50
Aurore 10 10 40
Cascade 10 10 40
Chelois 10 10 40
Syvol 20 10 45
De Chaunac 20 10 45
Chancellor 20 10 45

Pruning French Hybrids

There are several differences between the American and the French hybrid varieties in regard to growth and fruiting habit.

French-American varieties - require severe "suckering" of the trunk, head, and cordons during spring and early summer for satisfactory growth, plus crop and vine maturity. Use the formulas suggested in the above table.


Pests and Diseases

Birds can be troublesome, and netting may be necessary to protect developing clusters of berries. Major insect pests include Japanese beetles, sap beetles, grape phylloxera, and grape berry moth. Major disease pests include black rot, downy mildew, and powdery mildew.

"Black Rot" is a fungus disease which first infects grapes in the spring. The youngest plant tissue is most susceptible, but the disease also attacks leaves, young canes, tendrils, and fruit. Usually two weeks elapse between initiation of the infection and the appearance of symptoms -- spots on the leaves and vines. About midsummer, symptoms appear on the fruit. Light brown circular spots form and rapidly enlarge. Within seven to ten days, the berries shrivel and become black, dry and wrinkled. Spores of the disease overwinter in these mummified berries, in diseased leaves, and tendrils that have fallen to the ground. Good sanitary practices must be maintained to prevent the reoccurence of black rot next year. Remove and destroy all fallen, infected debris. Rake and remove plant litter under the vines.

"Downy Mildew" is another fungus disease which attacks grape leaves. There are two infection periods during the season, one in June, the other during late summer as nights begin to cool. Older leaves in the center of the vine are first infected. Light yellow spots appear on the upper surface. On the under surface, white, moldy spots develop. Eventually the leaves dry and crumble. As leaves mature, the disease spreads to the end of the canes. Because the leaves no longer offer protection from the sun, sunscald damage develops on exposed grapes causing them to ripen abnormally. During a June infection, fruit becomes soft and a downy mold develops. If infection occurs during late summer, the fruit turns brown, withers and shatters readily. Other effects include: malformation of tendrils, water-soaked depressions on shoots, and later, development of white mold. Again, sanitary cultural practices are good protective measures against this disease.

NOTE: From midseason to harvest the possibility of downy mold infection increases while the potential for black rot infection decreases.

Although not as important as Downy Mildew and Black Rot, "Powdery Mildew" also infects grapes. This disease usually attacks foliage and cluster stems, leaving a white, powdery growth. Eventually leaves turn brown and fall off. Berries turn rusty or scaly, fail to mature and split.


Other Problems

Problem: My grapes blossom heavily but never set fruit. Cause: Occasionally, a vine may have only male or female flowers.


Harvesting

Grapes should be harvested when fully ripe. Color does not always indicate maturity, so taste-testing is often the best method. Grape clusters should be cut from the vines with a sharp knife. Handle the clusters by their stems whenever possible. Grapes do not handle or store well, so use them as quickly as possible.


Related web pages:


Commercial suppliers:


Electronic mailing lists:


Suggested references:

If you are interested in any of the titles below, click on the title and it will take you to Amazon.com for ordering. Click on the icon at the left for more information.

Periodicals:


This page was last updated on November 16, 2002