With our changing climate and more and more erratic weather events being recorded both during a growing season, and just as importantly, during the dormant season, freeze injury is an on-going threat nationally for our grape and wine industry. In some areas, this means the more cold sensitive V. vinifera grapes, that our VQA wine industry has been built on, cannot survive winter temperatures without some form of protection. One method of protection is through the use of geotextiles, which are materials used for winter protection of crops, mainly in the nursery industry but are also used in some vineyards where winter temperatures can be severe.
|Here is an example of geotextile covering in a Prince Edward County vineyard.
There has been greater interest in these materials for vineyard use in Ontario and some growers, such as Rob and Sally Peck, Sugarbush Vineyards, are current- ly experimenting with them. Growers are concerned that through the current process of burying/unburying that vines can be physically damaged leading to crown gall infection and detrimental to soils through aggressive cultivation and hilling.
Furthermore, bud loss can occur due to physical damage as well as rot, particularly in wet springs and falls. Finally, timing of application and removal of protective materials and weather conditions are critical for good protection and prevention of premature bud break which can result in bud mortality due to freeze injury from spring frost.
Therefore, the use of geotextiles may be a way to eliminate these concerns while helping to increase and sustain production yields.
There is also potential for these to be used to grow more cold-sensitive varieties in Niagara.
Our research objectives were to:
- determine the effectiveness of geotextiles on mitigating damag- ing cold temperatures
- examine vine microclimate below the geotextile materials and how these impact bud hardiness and bud survival
- investigate different types of materials
- examine timing and removal of these materials on bud hardiness, bud survival, bud break, growth and yields
- help determine ‘best practices’ for using geotextile materials for cold protection in Ontario vine- yards
Established vineyard blocks in Prince Edward County (Wellington) and Niagara peninsula (Vineland) were selected for the geotextile trials. Two V. vinifera cultivars were chosen including a Chardonnay and a Pinot Noir cultivar. Geotextile materials were purchased from different suppliers.
|Control grapevine used for geotextile studies with reduced crop size.
||Grapevine which was protected using geotextiles and displaying
larger crop size.
The two materials used for this study included Hibertex Pro frost protection fabric from Dubois Agrinovation and ArboTherm from Texel.
Hibertex Pro is a white, non-woven fabric made of UV resistant polyester fiber. Arbotherm is a polyester felt on which a black LDPE has been applied underneath in order to render it waterproof. Two different widths of these materials were used to ensure proper coverage of the grapevines – six foot widths were used in Prince Edward County and 11.5 foot widths were required for use in Niagara. The geotextile materials were applied in vineyards during the week of November 13, 2012 and removed at multiple times during vine deacclimation.
During the trial, a number of observations were made. The use of geotextiles generally requires some pre-pruning in order to place the material over the vines. Mechanization and logistics of applying and removing geotextiles needs to be further studied.