Pierce’s disease is endemic in Fredericksburg area. Need to get resistant varieties of grapes.
Munson grape varieties that are tolerant: ‘Lomanto’, ‘Wine King’, ‘Beacon’, ‘Edna’, ‘Ellen Scott’ and ‘Carman’. ‘Champanel’ ‘Blanc du Bois’ and ‘Black Spanish’.
Blanc du Bois’ also resistant to downy mildew. Round, light-green berries. Ripens early July along Gulf coast.
Black Spanish is an American hybrid grape resulting from a cross of the American Vitis aestivalis species of grape with an unknown Vitis vinifera pollen donor. Also known as ‘Lenoir’ and ‘Jacquez’, Jacques, and El Paso.
‘Black Spanish’ is considered the current highest quality red wine grape variety that is tolerant to PD. Small,highly pigmented berries. Highly pigmented, strong flavor. Subject to iron chlorosis on calcareous soils if grown on own roots.
Some of the earliest comments on Lenoir of the late-1800s describe it as being a southern grape of the Herbemont class. Its bunches are loose, best to handle hot weather, and medium to large in size with dark round berries of bluish-purple to nearly black color. The grapes have a tender flesh that contains a juicy, sweet and vinous center that is very rich in coloring matter. In fact, Lenoir is one of the few grapes that actually bleeds red juice. In this era, viticulturalists describe its ripening qualities as “magnificent” for the southern United States, and quite acceptable for making red table wines.
A recent joint release by the University of Arkansas, Tarkington Vineyards and Texas AgriLife Extension Service, Victoria Red is a PD tolerant, seeded table grape that produces good yields of high quality attractive fruit.
Somewhat subject to freeze damage in winter. Needs at least Zone 7b situation.
Seibel 9110/ Verdelet
Vitis vinifera ‘Seibel 9110′
Hardy to -10F Not particularly disease-resistant, but grow well under a variety of conditions.
A table grape, clear (white) when ripe, Very prolific. One of the most popular and widely planted grapes in Texas. This grape hangs on the vine from 2 to 4 weeks after ripening. Ripens about Aug. 15th. Womack
Produces large, white, almost seedless grapes. Excellent for eating fresh or for juices and wines.
Seibel grapes are a group of wine grape varieties which originated with the work of Albert Seibel crossing European grape with American grape species to increase disease resistance.
SCHRANK MUSTANG GRAPE –
Vitaceae Vitis mustangensis
A trouble free native grape. Ripens early July. Produces a deep blue grape and makes an excellent low maintenance grape arbor. Will grow in high alkaline soils.
Mustang Grape is a high climbing vine that grows in the South Texas Plains and Edwards Plateau. It can grow up to 40 feet long. The crimson flowers grow in clusters which are between 2 and 3 inches long. The fruits mature between June and August and are clustered in groups of 3 to 12 and are about 1/2 inch to 7/8 inch in size. The fruits are black or very dark red in color and can irritate the mouth if the skin is not removed. Mustang Grape is generally free from disease and is well adapted to heat. Its dark green leaves are between 2 1/2 to 5 inches long and are covered with small white hairs. The leaves have an inverted-saucer shape and give the appearance of a shingled roof when the foliage is dense.
Although its fruit is usually pungent and unpleasant, the fruits of the variety diversa are actually sweet and have often been used in wine-making. This is a high-climbing vine which tolerates great heat and drought. The lower surface of its leaves is very white and densely hairy, a noticeable ornamental feature.
Bred and propagated by Nicholas Herbemont (1771-1839) of South Carolina and France, ‘Herbemont’ is purportedly a hybrid of Vitis vinifera, borquiniana, and aestivalis. ‘Herbemont’ has long been valued as a reliable producer of wine grapes and the vines are resistant to PD, phylloxera and several fungal pathogens. Along with ‘Black Spanish’ this variety has been heavily relied upon by Val Verde winery for the production of port wines. Resistant to PD
Other Resistant/Tolerant Varieties Other PD resistant or tolerant vines are available such as ‘Miss Blanc’, ‘Miss Blue’, ‘MidSouth’, ‘Orlando’ ‘Seedless’, ‘Roucaneuf’, ‘Daytona’, ‘Conquestador’, ‘Stover’ and ‘Lake Emerald’. While these can be grown without fear of loss due to PD, the ability of these varieties to successfully compete in the commercial marketplace is questionable.
Planting farther apart than recommended and deep watering once a week, rather than daily drip watering helps disease resistance.