0 a long, curved plastic structure that plants are grown under in order to protect them from the weather --
The original pilot design evolved into a lower cost solution using a lighter steel structure, similar to a multi-span polytunnel.
The bottom garden has a polytunnel which inside grows lettuce, tomatoes and other vegetables.
Every factor influencing a crop can be controlled in a polytunnel.
The education facilities include a range of national vocational qualifications, courses in industrial cleaning, hairdressing, beauty salon work, pottery, literacy classes, basic skills classes, market gardening, polytunnels and landscaping.
The polytunnel was daylit with variable temperature.
They examined 22 quantitative traits relating to leaf and flower bud size and developmental time, in plants grown in an unheated polytunnel.
