Winter Low Tunnel Protection Methods

Protection Methods

for OVERWINTERING in LOW TUNNELS

Quick Hoops™ are positioned over crops to be overwintered, then covered with Agribon-19 and secured when frost is expected. With the approach of deep winter they are covered with a layer of film and secured.

Johnny's Winter Growing Guide

Hoops, Covers, Ventilation & Temperature
Greens for production under low tunnels
Transplanting greens for winter low tunnel production

We developed the Quick Hoops™ Low Tunnel Benders specifically for creating hoops from bent steel conduit (aka electric metallic tube, or EMT). We have found that hoops made of EMT are strong enough to support heavy winter snow loads, whereas other materials, such as wire or PVC, fall short in this regard.

Using different bender styles, 3'-, 4'-, or 6'-wide hoops can be created, for fabricating low tunnels that span one or two beds at at time.

When frost is predicted, the hoops are covered with row cover (Agribon+ AG-19 or heavier) to extend the crop into the fall. These porous "blankets" protect the crop from frost while allowing them to respire and self-ventilate as temperatures fluctuate throughout the day.

After a few frosts, and once the chance of warm days has diminished, a layer of 4-mil (100-micron)-thick greenhouse film can be laid overtop the row cover.

If perchance warm weather occurs after the addition of the plastic layer, you may need to manually regulate internal temperatures, ventilating the low tunnels by lifting their sides then lowering them again as temperatures drop.

In the dead of winter, the tunnels will effectively be sealed shut by the snow load on top.

Following the winter solstice, the tunnels may again need to be vented intermittently, to prevent overheating as days grow longer and warmer.

Once the danger of hard frost has passed, the plastic can be removed completely, with the row cover remaining in place to protect the crop until it is time for early-spring harvest.

Learn More

To learn more about How to Set Up and Manage Your Quick Hoops Low Tunnels, see our excerpt from Eliot Coleman's Winter Harvest Handbook.