October 26, 2011

the wintergreens project

This project is looking at the practicality of growing lettuces, asian greens and other lovely salad greens in UNH greenhouses during the next two winter seasons.

Producing high yields of cool-loving crops would be beneficial for everyone.  Consumer demand for local produce is increasing, especially in the winter.  Most farmers are unable to keep up with the winter demand and can be hesitant to experiment during the cold months when heating is expensive.   

Of course you can grow plants in greenhouses you say- that is the point of a greenhouse.  What we are going to be looking at is how to use greenhouses without adding much additional heat, no additional light and using materials commonly used on a farm.  

On this blog we will be tracking our trials and successes through the winter and spring.     

low tunnels in the greenhouse

Temperature values used are from H. C. Wien's paper
"Use of low tunnels to improve plant growth in high tunnels"
Today we started setting up germination chambers on top of the existing greenhouse benches.  Really our germination chambers are just fancy low tunnels.  Low tunnels are simple hoop structures made from wire or PVC and covered with permeable fabric or plastic.  Their benefits are two-fold for organic and small farmers, they keep insects off plants and warm up the air.  We plan on using the increased temperature to our benefit.

If you put these low tunnels inside a greenhouse or high tunnel (unheated greenhouse) plants are even more insulated from the outside cold.  Our first trials using this arrangement will be looking at the temperature ranges using different materials as covers for the low tunnels.  Permeable fabrics, plastic sheeting and permeable plastic all have their benefits and drawbacks.