A Seasonal High Tunnel is an enclosed polyethylene, polycarbonate, plastic, or fabric covered structure that is used to cover and protect crops from sun, wind, excessive rainfall, or cold, to extend the growing season in an environmentally safe manner.

High Tunnels provide an intermediate level of environmental protection and control compared to open field conditions and heated greenhouses. They create a micro-climate inside the tunnel that raises the temperature and protects crops from potentially damaging weather. Crops tend to be of higher quality and produce higher yields than field-grown crops. Overall, high tunnels provide an energy-efficient way to extend the growing season, reduce or avoid use of pesticides, and reduce runoff and leaching of nitrogen into the soil. 

Benefits:

• Extend the growing season - plant earlier in the spring and grow later into the fall.
• Protect crops from frost, cold, excess rain and wind
• Improve plant health and vigor
• Increase crop yield
• Grow a wider diversity of crops that otherwise could not be grown outside
• Energy savings from local food production
• Improve local food security

Applicants must meet three tiers of eligibility for the Environmental Quality Incentives Program (EQIP): 

Producer Eligibility:

• Must have a social security number or employer identification number issued by the IRS (entities require a Taxpayer Identification Number).
• Must show control of the land (lease, deed or other agreement) for the length of the NRCS contract (typically three to five years).
• Must have an adjusted gross income of less than $900,000; however this requirement does not apply to Federally recognized Tribes and Alaska Native regional or village corporations.
• If the producer is an entity, must have signature authority to make management decisions on the land.

Land Eligibility:

• Land must have an agricultural production use such as cropland, rangeland, grassland, pasture or nonindustrial private forest land. Lands used for subsistence are also considered agricultural.
• The land where you plan to install the high tunnel must already be in agricultural production.
• Land must be in compliance with Highly Erodible Land and wetland compliance provisions. Your local USDA office can help you navigate compliance.

Resource Concern Eligibility

• There must be a valid natural resource problem on the land to receive NRCS financial assistance for the project. Typically with a high tunnel, the resource concern is poor plant productivity and health, though other concerns may apply. An NRCS conservation planner will conduct a site visit with you an help determine specific natural resource concerns on your property.

The frame can either be metal or wood. Polyethylene covers must be UV (ultraviolet light) protected. High tunnels are usually covered with a single layer of plastic and are passively-ventilated using roll-up side and end walls which can be opened or removed.

No. Greenhouses usually contain heaters and the plants inside them are grown in containers such as pots and trays. High tunnels don’t use heaters and the plants inside them grow directly in the ground in the natural soil profile. Unlike greenhouses, high tunnel systems are seasonal and are considered temporary structures. 

Crops must be grown in the natural soil profile or by installing permanent raised beds up to 12 inches in depth/height. Crops may not be grown on tables or benches, in pots, or hydroponically, for the NRCS conservation practice. 

No. The structure must be six feet or greater in height in the center; therefore, row covers and low tunnels do not qualify as high tunnels. But NRCS does offer a separate low tunnel conservation practice.

To receive financial assistance from NRCS, you must purchase a high tunnel kit, also called a manufactured high tunnel, from a commercial source. You may install a commercially-obtained kit yourself. 

NRCS requires a manufactured high tunnel obtained from a commercial source. These structures are sold as kits and generally contain all of the required materials and hardware to build the structure except for the lumber needed for baseboards and end walls. Individual kits vary by supplier and manufacturer. High tunnels must be planned, designed and constructed in accordance with the manufacturer’s recommendations. Not all manufactured kits meet NRCS specifications. See the NRCS Implementation Requirements Sheet from your local NRCS office for more information. 

Wood-frames and metal-frames have different requirements. Geodesic dome structures are not approved as a high tunnel system. Please see the NRCS Implementation Requirements Sheet from your local NRCS office for specifications. Vendor claims of meeting NRCS specifications must be verified by the participant. NRCS does not endorse any product, company or brand of high tunnel. 

NRCS prohibits the use of used materials for constructing a high tunnel. 

5 years according to the NRCS conservation practice standard. However if maintained properly, high tunnels may continue to function longer.

There is no maximum size limit to the high tunnel system, but there is a minimum height requirement of 6-feet at the peak of the structure.

Yes, but NRCS financial assistance is provided only for the structure itself. Electricity, venting systems, lighting etc. can be installed providing the additions meets manufacturer’s designs and specifications. However, the grower is responsible for those costs. 

NRCS strongly recommends that the plastic high tunnel cover be removed after each growing season to prevent the structure from collapsing under extreme snow loads. Management of the high tunnel will depend on climatic conditions. Consult the manufacture’s specifications and climate condition management in your area.

Your NRCS conservation plan specifies that you must maintain the high tunnel for 5 years and replace any damaged parts at your own cost. You are responsible for repair or replacement of a high tunnel damaged by ice, snow, wind, fire, flood, animals, or other causes. Failure to do so may result in termination of your contract and payback of liquidated damages. 

Since the high tunnel conservation practice is used to treat a natural resource concern, it must be placed on land where crops are growing in the natural soil profile, and where there is a demonstrated resource concern. Crops must be growing in the soil so that NRCS may identify and document any resource concerns associated with that cropland. The maximum ground slope allowed is 5 percent. 

High Tunnels may not be used for: 

• Growing crops on benches or in pots 
• Producing a substance that is federally restricted, such as marijuana. 
• Livestock or poultry production 
• Storage of equipment, furniture or supplies. 

Yes, but only if the additional high tunnel would be placed in a separate growing area (not the same location as an existing high tunnel or replacing a current high tunnel) and if there is a demonstrated natural resource concern on the site.