How to make a bamboo polytunnel
The clever people at Sunseed Desert Technology show you how to build a bamboo polytunnel step by step. You can also use these techniques to build one from hazel for year round food production.
We used a local renewable material, caña (like bamboo). You could use anything long and bendy – we would like to try it with hazel next time we are further north. The only items we paid for are the plastic and string (pita string made from fibres of the giant succulent Agave plant).
It took six days with four people working. It's a lovely material to work with, flexible, strong and graceful. The challenge throughout is to balance and work with the natural forces of the material.
Select locally growing caña and do a flex test.
Strip the outer leaves and bumpy nodules from the canes.
Bundle into a column of 7 canes tying with string at 25cm intervals.
Join one column to another to form a super column. This will be one of the main arches. Repeat 4, 5 or 6 times depending on the length and width of your polytunnel.
Dig holes to place feet of arches into. Fill in with yeso (gypsum is easily available at Sunseed but you could use a less ecological setting agent like concrete).
Create smaller columns of 3 canes to act as supports between main arches
Protect plastic by covering outside edge of all canes with fabric or folded netting/fleece.
Roll plastic over the structure. You can find sheeting instructions HERE.
Fit doors (we reused glass doors from a skip).
Grow plants all year round.
How to Grow Food in Your Polytunnel All Year Round has all the information you need to make the most of this precious covered space, including: • a crop-by-crop guide to the growing year • a dedicated chapter on growing for the 'hungry gap' • a sowing and harvesting calendar to help with planning • detailed advice on growing a wide range of crops • your tunnel's first year – timely advice for new tunnel gardeners.
Sunseed is a British / Spanish charity researching re-vegetation techniques and working with international volunteers to give them hands on experience of low-impact living. We aim to develop, demonstrate and communicate accessible, low-tech methods of living sustainably; and although based in a semi-arid environment much of what people learn can be applied elsewhere, particularly for those who pick up some of our permaculture ways of interacting with natural systems. For more information on any of our activities check out the website at www.sunseed.org.uk or email us at email@example.com
I read with interest this nicely illustrated article. As I am particularly interested in field practices to combat desertification, I am looking for techniques and methods to construct "sustainable" greenhouses. It has been shown that tunnels covered with a plastic create a lot of problems in the tropical drylands, e.g. destruction of the plastic by heavy winds. Therefore, I suggest to construct "live" greenhouses, using poles (branches) of easily rooting tree species. My own experiment at home in Belgium (A live teepee or tipi) was done with branches of the Navajo willow (Salix matsudana). See
More details on my live tipi can be found on my desertification blog.
a question ¿I can use local varieties of cane?
another question Life of the building ...?
http://es.wikipedia.org/wiki/Carricillo - http://www.sierradebaza.org/principal_07-02/notic1_07-02.htm
Great method. Could anyone elaborate on step 4 - how to join the columns to create a super column? I can't see how a strong join is made.