Storing seeds in a polytunnel - any advice?

Seeds need to kept dry, cool and dark, that will be difficult to achieve in a polytunnel. I'd keep them in your house for the time being. If you really are that short of space then a good sealed (like tupperware) container is a must.

 

Was going to say exactly the same as above, to be kept at their best an air tight container like above is best, if need be, you could bury it within a bag of compost or in the ground, this way the temp. will be lower as well as dark ........ Just don't forget where you've buried them