Variety Isabella

Isabella is an old variety of American origin, known since the 18th century; by the common definition it is a hybrid of Vitis labrusca with European grapes. A table-and-technical, universal variety: the berries are eaten fresh and made into juice and simple wines, and the bushes are often planted to green arbors and fences. It ripens late: from bud break to full ripeness 150–180 days pass, with a sum of active temperatures of about 3100 °C. The cluster is small, about 140 g, almost cylindrical or conical-cylindrical, of medium density. The berries are medium, round or oval, black with a bluish tint and a heavy waxy bloom, with slippery pulp and a distinct strawberry aroma. Sugar content 16–18%, acidity 6–7 g/l.

The bush is vigorous; fruitful shoots appear on old wood and replacement buds, so a crop is possible even after the main shoots freeze. Yield 60–75 centners per hectare. Frost resistance is high, and the variety is mostly grown without cover; it is resistant to fungal diseases and phylloxera, but crowded shoots promote downy mildew. It tolerates high humidity well and drought worse; it grows on fertile slightly calcareous soils. In northern areas, because of late ripening, the crop does not always have time to ripen.