High Tunnels Vary Greatly

Strawberries In High Tunnels

Editor’s Note: The story’s author, Thomas Walters (twwalters@wsu.edu) is a small fruit horticulturist at Washington State University (WSU)-Mount Vernon. Others working on this project include Debra Inglis, also of WSU-Mount Vernon; Annette Wszelaki and Jeffrey Martin of the University of Tennessee, Knoxville TN; and Russ Wallace of Texas A&M University, Lubbock TX.

Many consumers want locally-produced, organic strawberries, but growers know they are not easy to farm. Organic strawberry growers must contend with erratic seasonal production, weeds, fruit molds, and other diseases.

A team of scientists funded by USDA’s Specialty Crop Research Initiative has been addressing these problems in three very different locations: Knoxville, TN (subtropical climate with hot, humid summers), Lubbock, TX (semiarid climate with dry summers), and Mount Vernon, WA (dry summer subtropical climate with cool, humid summers). At each location, both June-bearing and day-neutral strawberry cultivars were grown using an annual production system, with raised beds, black plastic mulch, and drip tape. We compared production in high tunnels and in the open field at each location, choosing tunnels appropriate to each location.

Four-season tunnels were used at Knoxville and Lubbock, and remained in place for the duration of the experiments. The polyethylene film covers of the three-season tunnels used at Mount Vernon were taken down in late October each year, and were not replaced until the following April. Organic production practices were utilized in Knoxville and Mount Vernon, but some conventional fungicides, insecticides, and fertilizers were used at Lubbock.

Higher Yields

High tunnels dramatically increased marketable yields at Knoxville and at Lubbock. In fact, tunnels were essential to growing marketable strawberries at Lubbock, where seasonal high winds severely damaged plants and fruits in the open field, and rendered them unmarketable. In contrast, high tunnels did not significantly affect yields in Mount Vernon, although they did substantially decrease losses
due to gray mold.

High tunnels were marred by the weather in all three locations. In Knoxville, open field plants were severely damaged by a hailstorm, rendering the fruits unmarketable; tunnels protected the fruit, but the tunnel covers were damaged by the hail and had to be replaced.

At Lubbock and Mount Vernon, tunnels sustained damage from windstorms and had to be repaired or replaced. At Knoxville, the best yields came from the June-bearing cultivar Strawberry Festival, the day-neutral cultivar Albion, and Chandler, often described as a weak day-neutral. At Lubbock, Strawberry Festival was also the best producer, followed by LCN and Chandler. The day-neutral cultivars stopped producing once it got hot in Knoxville and Lubbock, generally by June. In contrast, the day-neutral cultivars San Andreas and Albion were the most productive in the relatively cool environment of Mount Vernon, where they produced fruit from June through October both years.

Plugs Vs. Bare Roots

We also compared plug plants with their bare root counterparts. Plug plants of Albion produced higher marketable yields compared with bare root plants, more than compensating for the higher cost of the plugs. It was also easier to plant plugs through the plastic mulch than to plant bare root plants. Strawberry plug plants are already widely used in the southeastern U.S., but are not commonplace in the rest of the country, so availability may be an issue.

High tunnels and annual growing systems contributed to producing good quality organic strawberries in three widely divergent climates. At Lubbock, they were essential to growing strawberries at all. However, to be successful, appropriate cultivar and tunnel construction choices need to be made according to location.

Tunnels Can Be Tricky

One of the toughest challenges in producing organic strawberries is managing gray mold, commonly caused by botrytis. Rotted fruit is of course unmarketable, and infected fruit can appear fine at harvest but develop symptoms just a day or two later, dramatically shortening shelf life.

In Mount Vernon, WA, where gray mold is prevalent, high tunnels reduced gray mold incidence to about 10% to 20% of that in the open field. However, incidence of verticillium wilt was higher in the high tunnels in 2010, possibly as a result of higher soil temperatures under the tunnels.

Topics: ,

Leave a Reply

Berries Stories

BerriesBotrytis Gray Mold Pressure Increasing With Humid Weather
September 15, 2014
Michigan State University researcher offers tips to reduce the spread of spores. Read More
BerriesNew Tracking System Could Improve How Companies Ship Fresh Produce
September 6, 2014
Researchers use RFID technology to find transport conditions suitable for strawberries. Read More
BerriesHigh Tunnels, Small Farms, And Strawberries
September 5, 2014
Saylor’s Farm experiments with hydroponic production yield earlier, higher-quality and more marketable crops. Read More
BerriesMichigan State University Extension Offers Tips To Prevent Leaf Rust In Blueberries
August 26, 2014
Humidity, rainy periods conducive to disease development. Read More
BerriesFamiliar Face Settles In As New Florida Strawberry Association Leader
August 14, 2014
Kenneth Parker’s deep roots in the community and knowledge of production challenges make a good combination for executive director role. Read More
BerriesNew Air Cleaner Inspection Conveyor Combo Now Available For Blueberry Packing
August 8, 2014
Low-cost packing equipment from Lakewood Process Machinery consists of a 30-inch-wide combo unit. Read More
BerriesLow Blueberry Yields, Cane Collapse Due To Winter Injury
August 5, 2014
Plants in Northeast, Michigan victims of polar vortex. Read More

The Latest

BerriesBotrytis Gray Mold Pressure Increasing With Humid Weath…
September 15, 2014
Michigan State University researcher offers tips to reduce the spread of spores. Read More
BerriesNew Tracking System Could Improve How Companies Ship Fr…
September 6, 2014
Researchers use RFID technology to find transport conditions suitable for strawberries. Read More
BerriesHigh Tunnels, Small Farms, And Strawberries
September 5, 2014
Saylor’s Farm experiments with hydroponic production yield earlier, higher-quality and more marketable crops. Read More
BerriesMichigan State University Extension Offers Tips To Prev…
August 26, 2014
Humidity, rainy periods conducive to disease development. Read More
BerriesFamiliar Face Settles In As New Florida Strawberry Asso…
August 14, 2014
Kenneth Parker’s deep roots in the community and knowledge of production challenges make a good combination for executive director role. Read More
BerriesNew Air Cleaner Inspection Conveyor Combo Now Available…
August 8, 2014
Low-cost packing equipment from Lakewood Process Machinery consists of a 30-inch-wide combo unit. Read More
BerriesTaste Tops Health Benefits For Blueberry Buyers
August 6, 2014
National surveys reveal flavor is what matters most to consumers. Read More
BerriesLow Blueberry Yields, Cane Collapse Due To Winter Injur…
August 5, 2014
Plants in Northeast, Michigan victims of polar vortex. Read More
BerriesStudy: Strawberry Web Tool Could Save $1.7 Million Over…
August 5, 2014
UF/IFAS researchers find spray advisory system also benefits the bottom line. Read More
BerriesNew Study Finds Simple Solution To Monitoring Spotted W…
July 31, 2014
UF/IFAS researchers are using a mixture of yeast, sugar, and water to lure, trap major berry pest. Read More
BerriesMichigan Blueberry Producer, Georgian U-Pick Operator A…
July 30, 2014
White House and USDA recognize 15 individuals who represent the next generation of farming and ranching. Read More
BerriesLargest Berry Processing Facility In Southeast Opens
July 23, 2014
Naturipe adds a second facility to its fresh and value-added processing capabilities. Read More
BerriesWish Farms Executive Set For Semi-Retirement
July 14, 2014
Longtime employee and sales leader Chuck Hollenkamp to take on a seasonal role. Read More
BerriesMichigan Blueberry Crop Suffers Winter Damage
June 26, 2014
Inland fields more affected, according to Michigan State University Extension agents. Read More
BerriesMidwest Growers Still Grappling With After-Effects Of C…
June 17, 2014
Growers note low cropping of peaches, berries, and some apple varieties. Read More
BerriesBlueberries Coated In Leaf Extracts Have Longer Shelf L…
June 3, 2014
Oregon State University researcher’s finding could mean extra weight, and could also mean extra cash for growers. Read More
BerriesReal Estate Company Snaps Up Oregon Blueberry Farms
June 3, 2014
Gladstone Land Corporation is targeting high-value fruit and vegetable farms across the country. Read More
BerriesLessons Learned From SWD In Michigan
May 27, 2014
Michigan State University Extension specialist reflects on what researchers have discovered from a few years of confronting spotted wing drosophila. Read More