Working in the vineyard during the last couple of weeks has required the crew to dodge a lot of rain drops. Rain in Iowa is usually accompanied by lightning and that makes a vineyard, with its miles of trellis wire, an extremely dangerous place to be.
On dry days, the vineyard crew has been planting Steuben vines, tying vines to the trellis in recently planted vineyards, and tucking vines up into the catch wires where we have vertical shoot positioning (VSP) trellis systems (Marquette and La Crescent).
So, how are our vines looking so far this year? The heavy and repeated rains have helped the vegetative growth (canes and leaves) like never before. Our vines are all very vigorous this year. One vineyard that looks especially good this year is Maple Woods where we have young vines that we’ve had a very hard time getting established. We first planted vines there in about 2009 and are finally getting vines that look like they are very strong two-year-olds.
Here is brief report on some of our varieties: Brianna looks very good. Marquette is beautiful and the harvest potential is good. Marquette is usually very vigorous so this year, we are attempting to balance that vigor with heavier crop loads. Marquette, Foch, Frontenac, La Crescent, and Brianna look the best. Our St. Croix, Sabrevois, St. Pepin, and LaCrosse all look okay.
The only problem variety this year is Edelweiss. The cold, cloudy, and wet days during the short period that Edelweiss was pollinating meant that few of the flowers were pollinated so we have very loose clusters with few berries. We will leave the suckers on the Edelweiss to take up the energy that this variety will have this year in order to balance the vine. We are learning that other grape growers in Iowa have had similar problems with Edelweiss this year.
Incidentally, we learned that many growers in Southern Iowa of Norton, Chardonel, and Chambourcin have experienced cold weather damage to their vines this year. These varieties are marginal in most years in Iowa.
In our last edition, we showed you a photo of Anne Hafar holding a rooted cutting. I include that photo again so you can compare a rooted cutting to a nursery vine. Our preference is rooted cuttings however they are not always available each year so sometimes we have to take what we can get.
Weather permitting, the vineyard crew will spray fungicide this next week in all vineyards. We must spray fungicides every 7 to 10 days in order to prevent powdery mildew, black rot, bunch rot, and other fungi from getting a foothold in our vineyards. Fungus is a big issue this year because of the amount of rain we are getting. We will also be very carefully applying herbicide under the rows to control weeds that will compete for water later in the season.
Finally, some of the vineyard crew will be removing suckers from Sabrevois, Brianna, and St. Croix at Tassel Ridge vineyard.