Manor Moments

Trailside Organic Farm December 2021 Update

December 2021

Submitted by Ian Frederick, Trailside Organic Farm Manager

Faint parallel trenches in freshly-tilled soil. A carpet of green stubble, determined to gain territory before snowfall. Dabbles of auburn leaves slowly retreat. Slender, woody soldiers remain, skirting the area to keep watch over the grounds. Scenes from the Trailside Organic Farm, December, 2021.

Poetic attempts aside- a farm is taking shape. The growing area has been plowed and disked, and a Winter Ryegrass cover crop has established. Our first growing season is on the horizon. As I’m preparing for spring production, the prospect of building a hoop house is becoming increasingly attractive. Hoop houses, high tunnels, caterpillar tunnels, low tunnels: these are different names for controlled environment structures which function similarly. Steel tubular hoops provide the structure and shape, while ground posts anchor the structure during windy days. Overhead beams called purlins run along the length of the structure to provide rigidity. A plastic covering is fastened overtop. This covering allows ample sunlight to reach crops while functioning as a heat absorber and a layer of protection against wind, rainfall and frost. As a side note, these structures are different from greenhouses. A greenhouse utilizes supplemental heating and its vents are temperature-regulated by thermostats. Hoop houses rely solely on passive solar lighting and heat. The grower must vent the structure manually to control temperature.

The capacity to extend the growing season is a key reason that hoop houses are popular among vegetable farmers. High tunnel growers of an array of crops including greens, brassicas and root crops are able to glean produce into the colder months, a time when the freeze-over can terminate growth in our region. A sunny yet chilly day will result in the hoop house and its soil absorbing heat, despite outside temperatures. Air temperature inside of the hoop house will drop once the sun goes down, but the soil will retain it. Soil temperature is extremely important for growing during cooler months; the warmer the better. Typically, high tunnel growers will cover their crops with row cover on cold nights. In preparation for especially freezing nights, some growers will add a layer of plastic overtop the row cover. Electing these supplemental layers will help keep soil and surrounding air pockets warm. Much of the time, cold-season crops can keep growing until sunlight becomes too scarce. In that case, some crops such as carrots will nonetheless hold over the winter for an early spring harvest.

As a controlled environment, hoop houses not only allow a grower to control heat, but also moisture. Seasoned growers attest that less-than-ideal watering patterns contribute to many growing problems, including diseases and crop failures. Since a grower cannot control rainfall- a hoop house is the closest thing! However, this means that a water source is always necessary for growing inside of these structures. Drip tape, overhead irrigation, sprinklers or even just a hose and spray nozzle are means to deliver the correct amount of moisture to crops. Hoop houses also cut down on pest pressure and can act as a barrier to weed seeds blowing in. This means fewer pesticide applications are usually necessary in a hoop house when compared to growing in the field.

At Trailside Organic Farm, I’m planning to compost the footprint of our imminent hoop house first, then till it in using a walk-behind rototiller. After the hoop house is constructed, the plan is to create semi-permanent beds watered with driptape. From there, the plan is to rotate through a lineup of vegetable and herb crops as the season progresses to supplement our field growing.

In closing, I’d like to extend a special thank you to John Long, plant production specialist at Rodale Institute, for mentoring me on high tunnel growing.