Gear up for extreme weather

Gear up for extreme weather

Use these tips to handle adverse weather conditions.

September 20, 2020

Weather cannot be controlled. But you can prepare for whatever Mother Nature decides to throw at you.

The year 2011 was particularly terrible for Prides Corner Farms. A record amount of snowfall, a hurricane in August that led to a week without power, a snowstorm in October with the foliage still on the trees, disposing of tens of thousands of boxwood due to a cylindrocladium outbreak, and an I.C.E. audit all added up to a year the Connecticut wholesale grower would rather forget.

“All PCF employees are forbidden to even mention the year 2011,” jokes Mike Emmons, nursery manager at Prides Corner Farms.

But some good did come of the difficulties the nursery faced that year.  Here are some tactics PCF learned to deal with extreme weather.

Reinforce your hoop houses.

Snow load has been a major issue for growers that overwinter plants in hoop houses, especially those in the Northeast U.S. PCF had several collapsed houses as a result of the massive 2011 snowfall.

In looking for potential solutions, PCF spoke with John Bartok, agricultural engineer and emeritus extension professor at the University of Connecticut (and frequent contributor to our sister publication Greenhouse Management). Bartok suggested PCF use wooden 2 x 4’s placed every five hoops (20 feet) to help secure the houses and prevent the snow from collapsing the structures.

“This works exceptionally well,” Emmons says. “Even when the snow is just too much for the steel, the 2 x 4’s prevent the house from falling in on the plants. You can replace a damaged pipe, but a damaged plant is unsalable.”

Know what your plants need.

Many plants require little more effort than an over-wintering structure and a white sheet of plastic.

Rhododendron PJM, Hydrangea paniculata and H. arborescens, taxus, spirea, and viburnum are examples of a plant that requires minimal protection from the winter.  A single covering of opaque plastic is all that is necessary. Other plants, like boxwood, buddleia, roses, and H. macrophylla require additional winter protection. PCF knows which of its plants require more care, and plans and acts accordingly.

Insulate vulnerable plants.

Another key to winter preparedness is the layout of your hoop houses. The coldest part of any hoop house is its ends. When setting up the hoop house for overwintering, PCF makes sure any plants that require additional protection stop 8 to 10 feet from each end of the house. Often, they will place tougher plants in those spaces left empty in houses containing more cold sensitive plants.  These plants are used as an insulation buffer and to maximize the amount of plants in each house. 

Photo: Syringa x Miss Kim are placed at each end of the houses containing evergreen holly as an insulation buffer and to maximize the open spaces in the house.

Also, beware of elevation changes! It might seem like a small aspect, but it can have a big impact. Some of PCF’s longer houses have as much as a 20 degree difference in temperature from top to bottom on a calm winter morning.  If you know which of your houses have more drastic elevation changes, they should be stocked with plants that are tough especially when the low end is the north end.

Tuck your plants in for the winter.

A 2-millimeter sheet of plastic is placed along the outside edge during the time the plants are placed in the fall. The “poly blankets” are usually 14 feet wide for one side of the house to accommodate a hoop that is placed inside over the plants to keep the plastic from touching when it is pulled over them. 

Emmons says it takes two people approximately 15 minutes to cover and secure the poly blanket in a typical 300 foot long house. An indication that the blanket was put on properly is when almost immediately a vapor film appears underneath the plastic.

Emmons says PCF uses 420,000 feet of poly blanket each year. That translates to 79 miles of film. 

The poly blanket can be used in the spring as well during the transition when plants become active but there can be fluctuations in spring temperatures. Emmons and his team at PCF are believers that the cost is well worth the protection it provides.

“A few of our houses are north/south orientation requiring a white poly blanket that faces the south side,” Emmons says. “Using a clear sheet on this side the temperature gets too warm and a white blanket keeps the temperature more stable.”

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