Table grape variety trial 2018-2022
To support Delta County’s burgeoning vineyard industry, OARSRM has both wine and table grape trial plots. The wine grape research is managed by Dr. Horst Caspari, CSU state viticulturist, professor, and research scientist at the Orchard Mesa Research Station. The vineyard was initially planted in 2005 as part of the NE 1020 regional rootstock project (a collaborative rootstock trial that was replicated across North America). Since the finalization of that trial in 2018, the wine grapes are a comparative source of data for cold hardiness and crop load potential. Research now focuses on monitoring and comparing the bud hardiness, yield, juice analysis, and plant survival of standout hybrid varieties like Marquette, MN 1200, Aramella, Chamberson, Vidal, and NY 81.
While wine grape production is not uncommon in Delta County, table grapes have been considered a more marginal crop. In order to determine if table grapes have potential as a crop in this area, as well as to establish variety recommendations, a table grape vineyard was planted in 2018. The trial consists of 20 cold-hardy varieties from all over the U.S. and Canada. Climate suitability is based on measurements of trunk survival, spring regrowth, bud hardiness, yield, and disease tolerance. Due to the extreme freeze event in October 2020, which caused 100% dieback in the vineyard, it has been difficult to fully establish the table grapes and determine if the crop is recommended for this area. However, several varieties, including Reliance, St. Theresa, Himrod, Thomcord, and Somerset show significant promise. Already, five low-performing varieties have been deemed unsuitable and replaced with new varieties.
- Identify most promising varieties for western Colorado growers based on:
- Winter hardiness
- Flowering and harvest dates
- Pest and disease resistance
- Adaptability to common production methods
- Market acceptance
- Fruit quality
- Identify potential for value added use (juice, raisin).
- Determine enterprise feasibility.
- Identify optimal production methods.
- Develop educational materials.
- Established fruit producers looking for alternative crops with higher likelihood of success in light of changing climate.
- New growers.
- Local and regional grocers/buyers.
Facilitate development of a new crop for the fruit growing industry in western Colorado. By identifying reliable and productive varieties of table grapes, and their best management practices for this region, growers may confidently produce this crop. This project will provide information to buyers and processors interested in increasing the variety of Colorado grown products to their customers.
- Field preparation – soil analysis, preplant application of compost to match recommendation, installation of irrigation, bare root plant 6’X10’ spacing, install trellis posts and 1st trellis wire. Install bamboo stake or hang training twine, initiate vine training as soon as growth allows.
- Pending irrigation forecast establish (or not) ground cover between rows.
- Hand weed and apply organic burn down herbicide in-row
- Based on the experience of Idaho, where table grape production has been very successful, and limited observation of a few growers successfully growing and marketing table grapes in our area, western Colorado should be able to produce a high quality product that will be well received in local and regional markets. It is expected that fruit growers will be enthusiastic about diversifying their operations to include crops that are less susceptible to late spring freezes.
- Develop and publish extension bulletins, present findings at annual research field days and WCHS conference.