Perennial Small Fruit Project

• Organic Table Grapes
• Organic Blackberries and Raspberries

Organic Table Grape Variety Trials

In 2003, the CSU Specialty Crops Program had a small demonstration plot of table grapes at the W.D. Holley Plant Environmental Research Center including the following varieties: Fredonia, Concord, Himrod, and Reliance. In 2004, a variety trial was established on certified organic land at the Horticulture Research Center northeast of Fort Collins, Colorado. Ten plants each of the varieties listed in the table below were planted 8' apart on June 16, 2004. We rented a tractor-mounted post hole digger to excavate the holes more efficiently. Half of the plants were treated with an endomycorrhizal root dip and half were left untreated. All vines planted were one year old vines (bare root stock), except for the variety Vanessa whose vines were 2-years old. We spread composted dairy manure on top of the soil in mid-summer 2004. The varieties Swenson White, St. Theresa, and Flambeau were potted plants and were obtained and planted on August 4, 2004. In 2005, 10 potted plants of the the variety Valiant were added to the variety trial and planted on May 16, 2005.

Varieties were chosen for productivity and cold hardiness, many having been bred in Wisconsin and Minnesota. Wind dessication can be a problem here, almost as much so as the cold temperatures, so it can be difficult for plants to survive the harsh conditions. We had 24% mortality of the grapes after planting and before the winter of 2004-05. In the spring of 2005, there was an additional 28% winter mortality rate. Interestingly, the treatment with the endomycorrhizal root dip did not appear to play a role in decreasing transplant shock or in aiding winter survival. By the spring of 2005, the grape plants with the endomycorrhizal root dip had 34% mortality and those without the treatment only had 22% mortality. Insufficient watering may have played a role in some of the mortality. During the summer of 2006, we watered more frequently, applying approximately 1" of water per week.

The plants will be trellised in the spring of 2006 and we hope to have our first year of grape production in the summer. See below for photos (all photos are courtesy of Cornell University) and descriptions of the planted grape varieties.

Photos (courtesy of Cornell Univ.)	Variety	Description
	Einset Seedless	Red seedless grape, strawberry-like flavor, medium sized clusters with good storage potential.
Photo Not Available	Flambeau	An Elmer Swenson variety, pink seedless grape.
	Mars	From the University of Arkansas, a blue seedless grape, has proven to be hardy in New York.
	Reliance	From the University of Arkansas (1982), red medium-sized seedless berries, among the best varieties for cold hardiness.
Photo Not Available	St. Theresa Seedless	An Elmer Swenson variety.
	Sheridan	Black Concord-type berries, seeded, vigorous, hardy, easy to grow, late producer.
	Swenson Red	University of Minnesota and Elmer Swenson variety, large, seeded, red berries, hardiness in Minnesota was marginal but did well in New York.
Photo Not Available	Swenson White	An Elmer Swenson variety, hardy white grape, ripens late in the season.
	Valiant	a deep blue-purple fruit, good for eating, jelly, and juice, very hardy grape, self-pollinating (photo courtesy of cornhillnursery.com)
	Vanessa	Red dessert grape, seedless, hardy variety, medium-sized firm berry, recommended as the best among red seedless types .

Other Sources of Information About Grapes

Photos are courtesy of Cornell University - see the link to their report on Table Grape Varieties for Cool Climates. See also the websites at the University of Arkansas and the University of Minnesota about their grape breeding programs. Jim Bruce at Rist Canyon Vineyards has been researching grape varieties at 7,200 feet in elevation, west of Fort Collins, Colorado.

Organic Raspberry and Blackberry Variety Trials

Five varieties of red rapsberries, two varieties of yellow raspberries, and two varieties of blackberries have been planted on certified organic land at the Horticulture Research Center northeast of Fort Collins, Colorado. The variety trial was established in 2004. The bare root stock raspberry plants were planted on June 11, 2004, 24" apart, one inch deeper than the nursery planted level, and the bare root stock blackberry plants were planted on June 14, 2004, 4' apart, to the same depth as the nursery planted level. We rented a tractor-mounted post hole digger to excavate the holes more efficiently. Composted dairy manure was mixed in with the soil when re-filling the holes.

Varieties were chosen based on hardiness, productivity, and early harvests. All raspberries being grown are fall bearing due to the ease of care (winter covering not needed, no pruning needed, can mow plants down in fall/early spring), and the ability to have some berry production in the first year. Yellow raspberries don't keep well and are best eaten fresh, so they are good for a U-pick type operation. Unfortunately we had high mortality in our raspberries and blackberries in 2004, so consequently many varieties were replanted in 2005. Of the varieties that made it through the first growing season in 2004, we had 28% mortality over the winter. We hope to have our first year of significant berry production in 2006. See below for descriptions of the berry varieties planted.

Last updated 3/1/06