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
BerriesSecond Florida Strawberry Picking Challenge Packs Philanthropic Punch
February 25, 2015
Fundraising event at Wish Farms in Plant City raises $76,000 for Redlands Christian Migrant Association. Read More
BerriesGrowing Greenhouse Strawberries Can Pay
February 24, 2015
British trial shows much lower disease pressure, higher quality and bigger yields. Read More
BerriesFlorida Blueberry Crop Sitting Pretty — Weather Permitting
February 18, 2015
Barring a hard-freeze event, growers agree the season’s offering looks fruitful. Read More
BerriesUniversity Of California Davis, California Strawberry Commission Settle Lawsuit
February 10, 2015
The renewed partnership includes plans to develop varieties with the addition of a new breeder for the UC Davis Strawberry Breeding Program. Read More
BerriesHow To Prepare For Strawberry Pathogens
February 5, 2015
From Botrytis in the East to Fusarium and charcoal rot in the West, strawberry growers need a plan of action to contain disease. Read More
Apples & PearsBiopesticide Use Quadrupled From 2000 To 2012
February 4, 2015
Biopesticides are on the up and up in U.S. agriculture as confirmed by recent data from EPA. “The use of Read More
Berries‘Fresh From Florida’ Produce Star Of New TV Ad Campaign
February 3, 2015
Commercials shine the spotlight on Florida blueberries, tomatoes, and seafood. Read More
The Latest
BerriesBuilding A Better Black Raspberry
March 27, 2015
Studies focusing on consumer preference, aphid resistance, heat tolerance, and genetics aim to capitalize on an expanding market. Read More
Fresh From Florida Strawberry Parfait recipe
BerriesNew Partnership Sends Florida Strawberries To Puerto Ri…
March 26, 2015
Latest addition extends Sunshine State’s agricultural export reach in the Caribbean. Read More
BerriesGeorgia Blueberry Growers Suffer Chill Damage
March 23, 2015
On early varieties, some growers lost as much as half their crops. Read More
BerriesSecond Florida Strawberry Picking Challenge Packs Phila…
February 25, 2015
Fundraising event at Wish Farms in Plant City raises $76,000 for Redlands Christian Migrant Association. Read More
BerriesGrowing Greenhouse Strawberries Can Pay
February 24, 2015
British trial shows much lower disease pressure, higher quality and bigger yields. Read More
BerriesFlorida Blueberry Crop Sitting Pretty — Weather P…
February 18, 2015
Barring a hard-freeze event, growers agree the season’s offering looks fruitful. Read More
BerriesUniversity Of California Davis, California Strawberry C…
February 10, 2015
The renewed partnership includes plans to develop varieties with the addition of a new breeder for the UC Davis Strawberry Breeding Program. Read More
BerriesHow To Prepare For Strawberry Pathogens
February 5, 2015
From Botrytis in the East to Fusarium and charcoal rot in the West, strawberry growers need a plan of action to contain disease. Read More
Apples & PearsBiopesticide Use Quadrupled From 2000 To 2012
February 4, 2015
Biopesticides are on the up and up in U.S. agriculture as confirmed by recent data from EPA. “The use of Read More
Berries‘Fresh From Florida’ Produce Star Of New TV Ad Campaign
February 3, 2015
Commercials shine the spotlight on Florida blueberries, tomatoes, and seafood. Read More
BerriesDormant Pruning Tips For Your Berries
January 28, 2015
Proper dormant pruning increases berry size and improves overall health of blackberry and raspberry plants. Read More
Apples & PearsA Better Understanding Of Biocontrol
January 27, 2015
The Biocontrols 2015 Conference & Tradeshow will help growers and PCAs incorporate new tools into their crop protection programs. Read More
BerriesWhy You Should Be Growing Black Raspberries
January 27, 2015
Amazing health benefits for consumers and production and marketing benefits for the grower make this berry a must-consider option for your operation. Read More
BerriesIf You Could Plant Any Type Of Fruit, Consider A Canebe…
January 23, 2015
Raspberries or a blackberries present some berry good options. Read More
Apples & PearsSurvey: Positive Indicators For Biocontrols In U.S. Hor…
January 22, 2015
Preliminary results of a survey conducted in December 2014 of more than 850 readers across six Meister Media Worldwide titles Read More
Apples & PearsReal-World Solutions Highlight First Biocontrols 2015 C…
January 22, 2015
Topping the inaugural event's marquee are presentations on “Driving Crop Quality and Productivity Using Biocontrols” by representatives from two of the largest produce growing organizations in the country. Read More
Apples & PearsRosBREED 2 Program Focuses On Disease Resistance And Qu…
January 19, 2015
The next generation of the federally funded RosBREED research program uses DNA techniques to deliver varieties that benefit both growers and consumers. Read More
BerriesCalifornia Strawberry Commission Awarded More than $1 M…
January 14, 2015
Strawberry farmers are dedicated to finding sustainable alternatives to fumigants such as methyl bromide. Read More