Double-cropping raspberries is a way to get two crops per season from one planting. The first crop is produced on floricanes in the summer and the second crop follows in the fall on primocanes. The V-trellis is one way to manage two sets of canes on one planting. This TunnelBerries’ video explains how to manage double-cropping with V-trellises.
The 2018 North American Raspberry and Blackberry Growers Association Conference (NARBA) in Ventura County, Southern California Feb. 21-24 was an excellent opportunity for growers and researchers to learn about berry production methods in this region of the U.S. Conference attendees toured several farms and the Hansen Agricultural Research and Extension Center. In the video clip below, C&N’s “Bug Vac” was demonstrated in the raspberry tunnels as one way to manage insect pests. Thanks to NARBA’s Debby Weschler and her California colleagues for another outstanding conference!
TunnelBerries has just published a video: "Raspberry Cultivars for High Tunnel Production". The seven featured cultivars include several new ones and covers performance and fruit quality of each.
I’m Maria Cramer-- a current Master’s student working on the Tunnel Berries project with Kathy Demchak and Rich Marini at the Pennsylvania State University. I joined the Tunnel Berries project in the fall of 2016. My research involves investigating possible changes the five types of plastics (and one uncovered treatment) on our 18 tunnels make to the pest populations inside the tunnels. The plastics have different qualities, transmitting varying proportions of UV and IR radiation. Literature and anecdotal evidence points to some of these impacting insect presence. This means I spend a lot of time picking Japanese beetles off of plants in the summer, and counting Spotted Wing Drosophila (SWD) samples in the winter. While quantifying the effects on these two particular pests, it’s also interesting to just observe the diversity of insects (and larger animals like tree frogs and black snakes) in our unsprayed high tunnels.
At this point in the winter, our plants are stored away from the fluctuating tunnel temperatures, and I’m spending my time counting samples, and analyzing data from the summer and fall. In the upcoming year, with two years of data on how the different plastics affect insect populations, I’ll look at how other cultural controls can be implemented for SWD. This includes assessing the effects of harvest intervals and the use of attracticidal spheres developed by Tracy Leskey’s lab in Kearneysville, West Virginia. The spheres are visually attractive to SWD and have wax caps that contain a feeding stimulant (a sugar) and a pesticide. These substances melt down to coat the sphere and SWD that land and feed on the sugar are poisoned. My overall goal is to develop strategies for SWD that would help organic and conventional raspberry growers reduce their pesticide usage and costs.
Data from the USDA Agricultural Marketing Service illustrate what remarkable growth has occurred in the fresh red raspberry market. American consumers have really taken a liking to fresh red raspberries and the “off-season” has nearly disappeared due to increased volumes from Mexico. It will be interesting to see how this changes over the next few years.
Average monthly fresh raspberry prices in Midwest grocery stores since 2014 indicate that organic prices have been 25-30 % higher than conventional prices. The data also illustrate how consistent pricing has become from month to month, particularly for conventionally produced berries which no longer spikes during the Midwest winter months.
Blackberry management and yields under multi-bay high tunnels at Michigan State University: We are protecting some tender blackberries by covering them with row cover during the winter. This winter will be a real test as temperatures have dipped below 0 degrees F regularly during the last few weeks. Last winter rabbits got under the row cover and girdled most of the Natchez floricanes so this winter we installed fencing to prevent a repeat. The 2017 yield data is: Triple Crown was the most productive in 2017 (equivalent of 21,790 lb/acre) followed by Obsidian (6,700 lb), Columbia Star (4,340 lb) and the girdled Natchez (1,640 lb/acre).
Check out this Informative article in the Washington Post by Elizabeth Pennisi on the work of Dr. Kim Lewers, plant breeder at the USDA in Maryland and TunnelBerries research collaborator. Every year, Dr. Lewers and her colleagues make dozens of crosses between day neutral strawberry selections and evaluate the resulting fruit with the goal of optimizing fruit size, appearance, overall yield, disease resistance and of course, flavor. Plants are grown in low tunnels and the marketable yield is three times that of plants grown in the open air.
More great press for local strawberries grown under cover in the eastern US!
Plastic recycling in agricultural settings is a big challenge. TunnelBerries researcher, Lois Levitan from Cornell University, has been working to build an agricultural plastic recycling network. Tunnel cover plastics are well-suited for recycling, but much depends on how materials are handled on the farm. Below are plastic film handling guidelines.
For more detailed information on the process of recycling agricultural plastics, see "Recycling Agricultural Plastics: What Have We Learned?" by Lois Levitan.
Register now for the Great Lakes Expo in Grand Rapids, Michigan and the New England Vegetable and Fruit Conference in Manchester, New Hampshire - both coming up during the first part of December.
It's the season for conferences! The Great Lakes EXPO and the New England Vegetable and Fruit Conference are two that are scheduled for the first part of December.
Reduced ultraviolet light transmission increases insecticide longevity in protected culture raspberry production
Michigan State University TunnelBerries personnel, Heather Leach and Rufus Isaacs along with colleague John Wise, recently published results from their study examining the effect of UV light transmission through different tunnel plastics on insecticide longevity in the journal Chemosphere. Results of this research indicate that tunnel plastics which block UV light transmission can prolong the effectiveness of insecticides used to manage insect pests.
We just finished the last harvest of potted raspberries in a high tunnel in Benton Harbor, Michigan. Plants were pruned last winter to two floricanes per plant. The relatively hot summer shortened the floricane harvest and reduced yields, whereas the long warm fall enhanced the primocane crop. Prelude had good yields this year, but produced small berries. For overall yield and fruit quality over the last two years, outstanding cultivars have been Kweli and Imara.
Newer raspberry cultivars being evaluated for both floricane and primocane production in containers under tunnels in Michigan include several standouts: Imara, Kwanza and Kweli all produce fruit that is large, glossy bright to light red, firm and with excellent flavor. Plants are still producing so final yield and fruit quality results for these and other raspberry cultivars will be available once the season ends.
TunnelBerries researchers Kathy Kelley and Kathy Demchak, both Penn State University personnel, will administer two Internet surveys to learn about growers’ experiences with high and low tunnels and consumer behavior and attitudes toward tunnel production. The goals of the two surveys are to gather information on topics related to use of the tunnels and plastics, with additional information related to production and marketing collected from current, former, and future growers of raspberries and strawberries.
By surveying current and previous high/low tunnel growers, the researchers can identify: 1) reasons why they grow/grew berry crops in the tunnels; 2) common obstacles (e.g., financial, marketing challenges, structural issues) they have encountered; 3) how they learn about plastic film features and what factors influence their purchasing decision; and 4) how they handle and dispose of plastic after being removed from the tunnels.
Growers who have not yet produced a berry crop in a high/low tunnel, but have plans to do so, will be asked to indicate: 1) what is primarily influencing their decision to grow berries in tunnels; 2) expectations regarding berry crop yields; 3) new markets they hope to serve with berries they harvest from the tunnels; and 4) any experiences they have had with selecting plastics, growing other crops under plastic films, and disposing of, reusing, and/or recycling plastics.
A survey will be developed and administered to consumers to learn about: 1) their berry purchasing behaviors; 2) attitudes and behaviors pertaining to recycling and local food production; 3) preferences when weighing plastics use vs. potential for reduced pesticide applications; and 4) response to price premiums associated with costs growers may acquire when using tunnels.
Responses to survey questions will yield the following outcomes:
TunnelBerries personnel Becky Sideman and Kaitlyn Orde recently had their strawberry research featured in the Boston Globe: Researchers extend growing season for strawberries>>