I get this question quite often! Mostly because we are using a high tunnel here in Anaktuvuk Pass. I thought I would share a bit about what a high tunnel is and how it fits our goals of sustainable living here in the arctic wild.
Our high tunnel consists of a sturdy steel frame, that is covered in special plant growing type plastic. The sides roll up for ventilation and the plastic is removable so that the plastic can be stored over the winter. Our high tunnel is 26 feet wide by 36 feet long and is 14 tall. It is what is referred to as a ‘gothic’ style high tunnel, which is a description of the shape of the roof. The roof is has a gentle ‘point’ rather than the rainbow curve, which allows for heavier loads of weight on top. We also have the extra rafter support kits installed. Both the shape and the rafter supports help the structure get through the winter with our high winds and hard core winters. The structure is also sunk down into the soil about 1 1/2 feet (it should be a bit deep but we had issues with rock). The whole structure is also next to a ten foot bank that helps shield it from the brunt of the the harshest winds from the North. It is aligned West to East, with the longest sides facing North and South. In the winter we DO NOT leave the plastic on. The reason being that our high winds would either shred the plastic completely OR the plastic would crush the steel frame completely like a tin can. We know this from talking with and learning from people who live in milder climates of Alaska and their experiences!
What does a high tunnel do and why is it needed here? Plants that are grown to produce food are usually pretty fragile compared to our more robust wild arctic plants. Our non stop winds, heavy sometimes cold rains, and rapidly changing temperatures can deter edible plants from growing. I myself have developed techniques to MAKE my outside backyard garden grow but they do grow slower, smaller, and with less edible bits. A high tunnel creates the PERFECT environment for maximum growth. The inside is warm, windless, and the temperature does not fluctuate quickly. It also protects the plants from harmful frosts, by holding a warm barrier of air around the plants.
We could have gone with a greenhouse structure, which is usually rigid clear walls of some sort, but I opted to get something more mobile. Though the structure is sturdy it can be taken apart and moved easily and does not have the expenses of the rigid panels and the shipping costs of those rigid panels. I figure we will need to replace the plastic on the high tunnel every three years and it will only run a few hundred dollars to do so. We can also upgrade our covering to the newest tech if we think it will fit our environment better.
It took us about a week to set up, only because there was NO ONE here that had put one up before (of course) and I enlisted the help of my husband that had an extensive background in construction and specifically building weird things in the arctic. And his professional OCD took a few days to make sure the structure was plumb and square! Which I am sure I will appreciate more someday! hahaha
The high tunnel itself was a donation from Petro Star, a ASRC company, that is working to help our villages become healthier and to encourage cultural activities and cultural growth. Without them we would NOT have been able to afford the high tunnel and the shipping costs! And we will be forever grateful. ❤
Please feel free to ask more questions, I’m sure I am forgetting some details!