Building a berm around garden to protect from frost
I live in Central Oregon, east of the Cascades in the high desert where we have a short growing season, due to late and early frosts, and cool nights all summer. We are going to be starting a new garden area that is at the bottom of a small slope and wondering if building a berm around it or partially around it would help hold the warmth of the day in, or if it would worsen the problem.
In July and August, we have warm daytime temperatures form 80-95 and it cools off to the 40's & 50's, even cooler sometimes, in the evenings. We would also like to plant some cold hardy fruit trees. Any suggestions?
I think a berm would help hold some heat, if only by protection from wind. If the garden is small enough, consider engineering a temporary framework that could be covered during super cold weather. I used 1.5''x 21' pvc pipe to build a ''quonset'' cold frame for tree and shrub winter protection. It was not 'pretty' or permanent, but it worked, and was easy to do. It was used for 5-6 years, 24'x80', and covered with a 40'x96', 6mil, used sheet of greenhouse plastic.