If you're constructing a greenhouse in a hot or cold area, temperature regulation can cause roadblocks. Here in Wyoming, we have had to get creative about how to efficiently manage temperatures in the easiest, most cost effective way. After much trial and error, we have found that 2 layers of 6mm polyethylene film, wiggle wire, and some pumped air can make all the difference.
What's With the Wiggle?
Wiggle wire connects two pieces of polyethylene plastic to the greenhouse sides using a wiggle wire channel, allowing for air to be pumped in between. This creates a cushion of air that serves as a temperature regulator between the inside and outside of the greenhouse. The wiggles in the wire easily secure the polyethylene to the receiving channel. Removing wiggle wire - so that the sides of the greenhouse may be rolled up for ventilation - is also simple.
Supplies to Gather
First, gather your supplies:
- Wiggle wire
PVC coated wiggle wire will be easier on the polyethylene plastic.
- Wiggle wire channel
We generally purchase wiggle wire channels in 6-feet sections.
- Polyethylene plastic greenhouse covering.
There are many materials available for greenhouse covers, including polycarbonate, acrylic, and polyethylene. Regular, opaque polyethylene plastic was chosen for our greenhouse because it is cheap, strong, and effective.
Installing Wiggle Wire
Ensure the two sheets of polyethylene plastic extend slightly past the ends of the channel. Insert one end of the wiggle wire into the channel so that it traps the two pieces of plastic between the wire and the channel. Wiggle the wire back and forth in the channel to secure. The bends in the wire are slightly larger than the channel, creating pressure and allowing for a tight, strong bond. Continue inserting and wiggling wire back and forth until it has secured all of the polyethylene plastic.
The Finishing Touches
After finishing the wiggle wire, attach a pump to inflate and create insulating air space between the two sheets of polyethylene. Secure the pump inside the greenhouse, and attach it to the innermost layer of poly. Pumping air in-between the plastic sheets provides desired temperature regulation.
To remove the wire, start at one end of the wire, and use pliers to pull the end out. Wiggle the wire to release from the channel. We re-do the wiggle wire 2 times per year - once to install in the fall/winter to ensure maximum insulation, and once to remove at the beginning of the summer for ventilation.
But is it stable?
While this may not seem like a stable structure, we have had incredible results using wiggle wire. In Wyoming, winds can regularly exceed 70 mph, and snows can be substantial and heavy. That is no problem for wiggle wire; it holds true though all elements. Polyethylene plastic coupled with wiggle wire is very strong. It has withstood all snow loads and other adverse weather.
Though some growers are skeptical of wiggle wire, we have found it to be cheap, effective, and easy to install. The benefits in temperature control and improved temperature consistency allow for better results from any system. While wiggle wire may take some time and money to get started, the benefits are game-changing, and we encourage all growers to give it a try.