How To High Tunnel

Help with High Tunnels

There is increasing interest among some growers in the use of high tunnels for vegetable production. Florida Grower and its sister publications hosted a webinar this past fall on the topic. More than 350 people signed up to view the webinar, which covered the areas of irrigation, soil management, and use of biocontrols in high tunnels.

Matt Kleinhenz, vegetable specialist with The Ohio State University, discussed the importance of cultural management in high tunnel production. “An ounce of prevention is worth a pound of cure,” he says. “This is true in high tunnel production. A proper cultural management plan is a cornerstone in integrated crop management and integrated pest management and helps reduce the need for pesticides, fertilizer, and possibly water.”

One of the most important items in high tunnel production is having a clear picture of the soil type or medium being grown in and its ability hold water and fertilizer. Understanding a particular crop’s needs for both changes with the season and growth stage also is critical to successful production. “The goal is to apply just the right amount of water and nutrients,” says Kleinhenz. “Too little or too much of either has bad consequences.”

To manage water and nutrients correctly, Kleinhenz recommends a whole farm planning approach, which takes into account nutrient uptake, binding, leaching, and runoff. In simple terms, you keep track of the fertilizer that enters the high tunnel and leaves the high tunnel in its different forms. This requires good recordkeeping, but it pays off in ensuring proper fertilization.
Soil sampling is another very important process in whole farm planning. “It represents a small fraction of total production costs with a potentially high return on investment,” says Kleinhenz. “We also recommend petiole testing, so growers can fine tune fertility needs as the crop grows.”

Hand In Hand

Soil fertility and moisture management are tightly linked. Fertilizer must be dissolved in the soil solution to be taken up by the plants. “Nutrients flow with water,” says Kleinhenz. “Most high tunnels are drip irrigated and soil type affects the wetting pattern at the emitters.”
Clay soils tend to create wider, flatter wetting patterns, while sandy soils create deeper, narrow wetting patterns. Soil type should be taken into account to adjust emitter spacing, irrigation timing, and intensity. This ensures water and nutrients are distributed in the root zone and not wasted outside or below it. Frequent and short bursts keep water and nutrients high in the soil profile, while less frequent and longer irrigation drives nutrients and water deeper.

Amend And Rotate

Kleinhenz notes that soil quality often declines as a result of vegetable production. Therefore, it is important to amend the soil to help raise organic matter. In addition, rotation of crops helps maintain soil quality as well. “Adding organic matter tends to help the overall health of soil and its ability to hold water,” he says. “Installing raised beds with soils made to order for crops and a good rotation also are very popular and effective methods for maintaining good quality soils under high tunnels.”

Additional Options

Kleinhenz suggests growers consider other options like soil solarization to help kill weed seeds and some insects. In Florida’s sunny, hot, and humid environment, the practice can be effective.
 
Finally, grafting on plants like tomatoes shows promise. “In tomatoes, we start with two plants,” he says. “The rootstock variety shows us some advantages with greater vigor and disease resistance, but also could include an ability to take up nutrients and water more effectively.”
Trials show grafted tomatoes on deficit water can produce similar yields to ungrafted tomatoes on standard irrigation programs.

Biocontrol’s Role

During the webinar, Michael Orzolek, a horticulturist from Penn State University, discussed the use of biocontrols in high tunnel production. He pointed out that cultural management of high tunnels falls somewhere between field production and greenhouse production.
“We have studied the use of biocontrols and predatory insects in greenhouses for years and have adapted this knowledge to high tunnels,” says Orzolek. “In greenhouses, we’ve found these predators to be very effective in controlling insects like whiteflies, aphids, and spider mites.
“If you are interested in trying biocontrol methods in your high tunnel, start small and learn the system first. Start with 600 to 2,000 square feet where you find a problem and initiate your biocontrol program and manage the problem over time.”

Clean Start

As in field production, sanitation is critical in high tunnel production. When planting, remove debris from the previous crop and work to avoid residual pesticide residues when planning to use predatory insects.
Orzolek also recommends seeking out disease- and insect-free transplants. He advises growers not grow ornamental and vegetable transplants together, because this can spread disease and pests among the crops. “If you start out with problems in your transplants, it will be a long-term problem,” he says.
Keeping weeds controlled around the high tunnel is another important step in keeping pest numbers low. “Because weeds can serve as a reservoir for some insect pests, if there are enough outside the high tunnel, it can upset the balance of predator to prey inside the tunnel. We really like a situation where it is fairly clean outside the tunnel because of the pests and the fact weeds also can harbor viruses.”

Leave a Reply

Featured Stories
Irrigation
March 26, 2017
Tips to Maximize Water Efficiency
Editor’s note: Spencer Cooper joined the Almond Board of California last fall as Senior Manager, Irrigation and Water Efficiency. Western Read More
SWD On Raspberry
Berries
March 26, 2017
Outsmarting SWD with Social Media
Entomologist in Kentucky uses social media for pest updates, trap catches. Read More
honeybees
Citrus
March 25, 2017
New Videos Offer Tips on Planting Pollinator Habitats
A new video series on planting flowering habitats is designed to help growers support crop pollinators. Read More
Freeze protected blueberry bushes in Florida
Berries
March 25, 2017
Florida Blueberry Crop Escapes Slap from Late-Season Cold Snap
Freeze protection tactics prove fruitful as local producers look to gain from Georgia’s loss. Read More
Apples & Pears
March 25, 2017
Two MAIA Releases Available for Growers, Hobbyists
‘Crunch-A-Bunch’ is an early ‘GoldRush’ and ‘Bakers Delight’ is a secret ingredient for baking. Read More
Nuts
March 24, 2017
Foreboding Fungus Vexes Almond Growers
In parts of California, almond growers have recently become concerned about Ganoderma root and butt rot. To put this concern Read More
Citrus
March 24, 2017
Marrone Bio Introduces Biostimulant to Reduce Sun Stress
Haven Anti-transpirant helps to reduce transpiration of fruit, nut, and vegetable crops. Read More
Campus of Massey University in New Zealand
Citrus
March 23, 2017
Count Down the World’s Top 30 Agriculture Colleges
Familiar names, and several new faces among annual ranking’s elite. Read More
Pest Control
March 22, 2017
Fear of GMOs is Impacting Quality Food Research [Opinion]
Perhaps the greatest threat to our industry is a public that values instinctual opinion over careful research and the findings of experts who have dedicated years to their field of study. Read More
Business Planning
March 22, 2017
How HortTech Is Solving Grower Challenges
Dozens of tech companies are looking for solutions to real-world problems vegetable growers face. We take a look at what it could really mean for you and your business. Read More
Production
March 22, 2017
Weighing the Good and Bad of Six Soilless Media Options
Trying to decide which growing media is the right one for your greenhouse vegetable production? Take a look at these six options. Read More
Citrus
March 21, 2017
Industry Groups, Ag Leaders React to Proposed USDA, EPA Budget Cuts
New plan would slash USDA spending by 21%. Read More
Freeze protected peach trees in Florida
Cold Protection
March 21, 2017
Freezing Temperatures Hit South Carolina Crops Hard
Peaches, blueberries, and strawberries among crops damaged. Read More
fork digging into a plate full of salad
Citrus
March 21, 2017
Since When Did Eating Get So Complicated? [Opinion]
The bottom line to all this is the way we eat is undergoing massive disruption. Read More
Apples & Pears
March 21, 2017
Two More Lost Apple Varieties Found In Steptoe Butte
Amateur apple detective strikes again with two more finds in abandoned orchards near state park. Read More
The Latest
Irrigation
March 26, 2017
Tips to Maximize Water Efficiency
Editor’s note: Spencer Cooper joined the Almond Board of California last fall as Senior Manager, Irrigation and Water Efficiency. Western Read More
Berries
March 26, 2017
Outsmarting SWD with Social Media
Entomologist in Kentucky uses social media for pest updates, trap catches. Read More
Citrus
March 25, 2017
New Videos Offer Tips on Planting Pollin…
A new video series on planting flowering habitats is designed to help growers support crop pollinators. Read More
Berries
March 25, 2017
Florida Blueberry Crop Escapes Slap from…
Freeze protection tactics prove fruitful as local producers look to gain from Georgia’s loss. Read More
Apples & Pears
March 25, 2017
Two MAIA Releases Available for Growers,…
‘Crunch-A-Bunch’ is an early ‘GoldRush’ and ‘Bakers Delight’ is a secret ingredient for baking. Read More
Nuts
March 24, 2017
Foreboding Fungus Vexes Almond Growers
In parts of California, almond growers have recently become concerned about Ganoderma root and butt rot. To put this concern Read More
Citrus
March 24, 2017
Marrone Bio Introduces Biostimulant to R…
Haven Anti-transpirant helps to reduce transpiration of fruit, nut, and vegetable crops. Read More
Citrus
March 23, 2017
Count Down the World’s Top 30 Agricultur…
Familiar names, and several new faces among annual ranking’s elite. Read More
Pest Control
March 22, 2017
Fear of GMOs is Impacting Quality Food R…
Perhaps the greatest threat to our industry is a public that values instinctual opinion over careful research and the findings of experts who have dedicated years to their field of study. Read More
Business Planning
March 22, 2017
How HortTech Is Solving Grower Challenge…
Dozens of tech companies are looking for solutions to real-world problems vegetable growers face. We take a look at what it could really mean for you and your business. Read More
Production
March 22, 2017
Weighing the Good and Bad of Six Soilles…
Trying to decide which growing media is the right one for your greenhouse vegetable production? Take a look at these six options. Read More
Citrus
March 21, 2017
Industry Groups, Ag Leaders React to Pro…
New plan would slash USDA spending by 21%. Read More
Cold Protection
March 21, 2017
Freezing Temperatures Hit South Carolina…
Peaches, blueberries, and strawberries among crops damaged. Read More
Citrus
March 21, 2017
Since When Did Eating Get So Complicated…
The bottom line to all this is the way we eat is undergoing massive disruption. Read More
Apples & Pears
March 21, 2017
Two More Lost Apple Varieties Found In S…
Amateur apple detective strikes again with two more finds in abandoned orchards near state park. Read More
GenNext Growers
March 20, 2017
Packaging: A Powerful Way for Farmers to…
Growers have few opportunities to communicate with end users. Paying mind to what’s on the outside can help sell a lot of what’s inside. Read More
Crop Protection
March 20, 2017
Biologicals Gaining Acceptance Among Mor…
Driven by new innovation and consumer demand, growers look to the biocontrol sector for new solutions. Read More
Disease Control
March 17, 2017
Prevent Alternaria from Putting Your Sna…
Learn how to identify, the survival and spread, as well as management methods for this vegetable disease. Read More