More to explore:
wilipini underground greenhouse in zone 4b, going to grow citrus
Zone 4, unheated greenhouse, January lettuce.
Sugar snap peas in January, zone 4, unheated greenhouse.
Simple Ideas That Are Borderline Genius – 32 Pics
Greenhouse full of rosemary topiary.
the whole website is greenhouses from recycled doors and windows ....lots of ideas
Growing Garlic/Best advice ever on garlic growing
A guide to hardy plants for multiple zones with tips and ideas for a successful perennial garden.