Grape rootstocks for Michigan: New publication with recommendations for the region’s needs
Michigan vineyards need rootstocks that provide some cold tolerance while also resisting Phylloxera and nematodes. This bulletin suggests the best standard and experimental options.
Michigan vineyard owners have a new bulletin, “Grape Rootstocks for Michigan” by Michigan State University Extension, to help with selecting rootstocks. This bulletin focuses on the use of grape rootstocks to suppress soil pests, control vegetative and reproductive activities of the grapevine with recommendations for Michigan vineyards. The history of using rootstocks is relatively recent because grapes can readily be propagated via cuttings. The practice of grafting grape scions onto rootstocks was established by the Romans. It was not until the middle 19th century, when the European wine grape industry was devastated by the Phylloxera root aphid, native to eastern North America, that the practice took a global trajectory.
Extensive experimentation and breeding followed in France to identify selections of North American species and their hybrids that could serve to abate the problem. Those early rootstock selections resulted in the foundation of progeny for subsequent contemporary breeding programs and the development of commercial clones. The rootstocks developed in 1880 and in early 1900 still dominate the genetic arsenal available to growers and nurseries today. Unfortunately for growers in the Midwest and Eastern United States, these standard rootstocks address European problems which are primarily calcareous soils, high soil pH, high salinity, drought and Phylloxera. Many regions in Europe, by virtue of appellation rules, are not allowed to irrigate and thus drought tolerance is a critical attribute in rootstock selection. We do not confront many of these problems in Michigan vineyards where our soils are slightly acidic and coarse along with supplying needed moisture via micro irrigation systems.
Our most critical needs are for rootstocks which can influence the canopy to mature early in a season in hopes of providing some cold tolerance and resistance to Phylloxera and nematodes. Rootstock selection can be the most sustainable approach to addressing soil pest problems. There is a general assumption that vines grown on their own roots produce fruit and wine with superior quality compared to those grown on rootstocks. Unfortunately, there is no empirical evidence to support this theory, as discussed in this bulletin. This bulletin suggests the best standard and experimental rootstocks for Michigan and points to the need for establishing future rootstock trials.
For a print copy of the bulletin, purchase publication E3298, “Grape Rootstocks for Michigan,” at the MSU Extension Bookstore. A free PDF and additional content can be downloaded at the Growing Grapes for Juice and Wine website.