Editor's note: This article was produced in 2002 in response to the frost conditions. The original article can be found at: http://www.ipm.msu.edu/CAT02_frt/F04-30-02.htm#6
As a result of last week's frost, many grape growers are looking at vineyards that will not produce an economic crop this year. Following on the heels of last year's poor crop, growers will not want to spend much money on their vineyards. It is tempting to just ignore your vineyards this season and cut your losses. An important thing to remember is that many of the buds that push now may be fruitful. It is important to get a handle how much crop you may actually end up with. Areas that look like a disaster now may have a marketable crop at harvest. The vines will also be growing wood for next year. With little fruit on these vines, their energy will go into shoot growth. Like last year we will end up with lots of shaded wood that makes for poor fruiting canes. Shaded buds have reduced fruitfulness. In frost-damaged vineyards you need to keep costs down and develop good wood for next year.
I think one of the most important things growers can do is shoot positioning or combing this summer. Positioning shoots outward decreases shading and eliminates running brush. Positioning the shoots downward slows their growth, preventing excess wood development. Lots of growers will be doing mechanical pruning next year to save money and this is very effective on vines that are set up for it rather than a mess you walked away from last year. Combing will also increase the effectiveness of the pesticides that you apply.