PES Their Characteristics and Suitability for Production in Washington EB 635 January 1972 Cooperative Extension Service College of Agriculture Washington State University Pullman Contents Kinds of grapes 3 The American-type grape 3 The European-type grape 4 Hybrids-French and American 5 General response to environment 5 Winter injury 5 Influence of length of growing season on selection of grapes 6 Heat units during the growing season 6 Influence of soils on grape production 7 Precipitation, diseases, and soil moisture 7 Selecting grape varieties and vineyard locations 8 Summary 12 Tables 1. California grape classification system 7 2. Desirability of soils for various types of grapes 7 3. Relationship between length of growing season and performance of grapes 8 4. Accumulated heat units at various locations in south central Washington 10 5. Grouping of grapes by vigor and maturity 11 6. Classification of potential sites for grape production in central Washington 11 Figures 1. Mean length of growing season, mean number of frost-free days 9 2. Mean number of days over 28 degrees 9 3. Approximate relationship between heat units and number of frost-free days 10 2 Grapes-Their Characteristics and Suitability for Production in Washington By Ronald B. Tukey and Walter J. Clore* There is renewed interest in producing grapes wilds which are now referred to as the "American­ in the state of Washington. Although grapes type" grape. Most have a strong "foxy" flavor have been grown in commercial quantities for a and aroma, a tender flesh, and "slip skin." Con­ hundred years, problems in developing markets cord is the best known and most widely cultivated have always limited expansion of the industry. variety of this type. Until recently, only small quantities of grapes Crosses have been made between the more have been used for wine. About 90 per cent of hardy, wild American grapes and the European the total crop has been of the variety Concord, vinifera. These have resulted in the so-called produced for the grape juice market. hybrids (American and French) grown primarily The development of new irrigable lands in in the northeast United States and southeast Can­ central Washington has focused attention on ada. grapes as an alternate high-value crop. New meth­ European varieties introduced into Mexico and ods of trellising grapes have increased yields while California found a warm, dry climate which fa­ the introduction of mechanical harvesting has of­ vored their growth. They are the base upon which fered distinct advantages for managers of large the large California fresh table grape, raisin, and acreages. wine industries have developed. Some are grown At the same time, there has been a sudden in­ in the very warm interior valleys while others are crease in the demand for grapes for wine. In­ better adapted to the cooler valleys along the volved are premium type table wines as well as coast. new wines utilizing large quantities of Concord While there are still other types of grapes, it and other American-type grapes. The lack of is the American, European, and hybrid which are additional land in California and New York­ of primary interest in Washington. Pennsylvania suitable for large acreages has at­ tracted the wine industry to Washington. This publication outlines some of the major The American-Type Grape differences between the various types of grapes The American-type of grape is known for its used for juice and wine and to indicate how each slip skin, soft flesh, and distinctly musty or "foxy" is adapted to conditions in Washington. flavor and aroma. Developed in the Northeast, it is characteristically hardy and resistant to a large Kinds of Grapes number of diseases and insect pests. Varieties are moderately vigorous, highly productive, and ma­ Grapes are one of the oldest and most widely ture early in the season. distributed fruit crops in the temperate zone. For There are about 300,000 tons of American­ thousands of years, they have been used as a type grapes produced in the United States. New source of fresh fruit, dried into raisins, or pressed York is the leading state, producing about half into juice for wine. Early Europeans who came of the total. Washington is second with 55,000 to America as traders, missionaries, and settlers to 60,000 tons. It is followed by Pennsylvania brought with them varieties prized in their own and Michigan. About 80 to 90 per cent of this native countries. Here they found other types of production is of the variety Concord. grapes used by the Indians. The variety, Concord, as well as most other Attempts to grow the high quality European American-type varieties, is not well adapted to vinifera-type grapes in the eastern part of America met little success. Cold and disease were the major problems. Instead, the early pioneers de­ * Extension Horticulturist, Washington State University, Pull­ man, and Research Horticulturist, Washington State University veloped new varieties from grapes found in the Irrigated Agriculture Research and Extension Center, Prosser. 3 growing conditions in California. In contrast, produce various kinds of wines. New varieties production per acre in Washington is almost twice were developed for the warm interior valleys and as high as in any other state in the nation. for other kinds of markets. As a result, there are The principal market for the American-type rna jor differences between the European grape grape has been the large centers of population industry and those associated with California al­ in the Northeast. It is marketed in three ways. though both are based upon the same general type JUICE AND JELLY MARKET. This is the (species) of grape. largest market for American-type grapes. It de­ GENERAL CHARACTERISTICS OF EUROPEAN­ pends almost exclusively upon the variety Con­ TYPE GRAPES. The differences between the Eu­ cord. In recent years, per capita consumption of ropean-type grape varieties and the American types Concord juice and jelly has been declining. Com­ involve not only the fruit but also the vine and petition from eastern production has limited ex­ its adaptation. Characteristically, the berries are pansion in Washington. firm-fleshed, nonslip-skin and relatively mild fla­ WINE MARKET. The use of American-type vored. Most varieties require comparatively warm grape varieties for wine is primarily a develop­ weather and a long growing season to mature. ment of wineries in the eastern part of the United The vines are vigorous and produce heavy, upright States. About 20 per cent of the production of growth requiring special trellising and attention grapes in the East is utilized on this market. Pre­ to soils and soil management. They are quite ferred are such varieties as Delaware, Catawba, tolerant of heat, drought, sandy soils and soils of and Niagara rather than Concord. a relatively high pH. These are some of the char­ Only about 5 per cent of the production in acteristics which make this type of grape more Washington is utilized in this manner. Com­ subject to winter injury, particularly under north­ petition from California wine produced from ern conditions where the growing season is short European-type varieties has limited the develop­ and midwinter temperatures go down to zero and ment of these Eastern-type wines in Washington. below. Recently, a new sparkling burgundy-type Another important difference between the wine, using the variety Concord as a base, has European-type grape and the American relates been developed and marketed as "Cold Duck." to susceptibility to insects and diseases. Downy The acceptance of this sweet wine has startled the mildew and fruit rots limit the development of wine industry and created a new demand for Con­ plantings in the more humid conditions of west­ cord juice. It is this new, relatively unknown ern Washington. A number of different grape market development which has stimulated Con­ viruses are of major concern. They reduce vine cord grape prices and the rapid expansion of the vigor and productivity and increase the suscepti­ Concord grape industry in Washington. How long bility to winter injury. this market will continue is unknown. Nematodes and the grape phylloxera are other FRESH MARKET. The sale of American-type concerns. Certain soil-borne nematodes transmit grapes on the fresh market has been limited. Some viruses from infected to healthy plants. The grape grape varieties are used by homemakers for wine phylloxera is a louse which feeds on the roots. as well as juice and jelly. A few are still eaten Both conditions require the use of resistant root­ as fresh grapes. Campbell Early has been the stocks. chief variety used in Washington for this type of Fortunately, phylloxera has not been a prob­ market. Its potential has not been fully explored, lem in Washington. While nematodes are pres­ but it is undoubtedly limited in comparison to ent, plantings have been remarkably free of major other uses of the American-type grapes. viruses. As a result, European grapes can be prop· agated from cuttings and grown on their own roots in Washington. In California, special root­ The European-Type stocks are required. (Vinzfera) Grape WINE MARKET. While small in comparison to the raisin and fresh grape markets, the market When the European grape was brought to for wine is expanding. European varieties are the California, it underwent tremendous change and principal source of sparkling, dessert, and table redevelopment. Varieties associated with specific wines. The first two types of wine represent the grape-growing regions of Europe were utilized to largest market. Varieties used for this purpose 4 are best adapted to the hot, dry, and long growing hybrids has been in the cooler growing regions season found in the interior valleys of California.