Hi! My husband and I are digging out an underground greenhouse in our backyard. The plan is 9'x9' and 6' deep, with mounds in the corners 2' raised above the path running down the center which has another path that crosses it in the middle. It'll be like a plus sign with four 2' high "tables" to grow plants on. There'll also be stairs outside the greenhouse leading in and we'll cover them with a roof to protect from weather.
It's a humble start but it's both of our first time doing something like this so hopefully it'll be a good learning experience. I've included our progress photos so far. Any advice on what materials to build the roof out of as well as general greenhouse advice would be appreciated. We live in zone 4 for context.
Thank you for any advice you guys can offer!
by Erinaceous42
4 Comments
the technical term is Walipini!
What’s your plan to deal with water intrusions in a 6′ deep underground greenhouse? In my area you are digging a pond.
Ah! I see you have hard clay too! I’ve been digging in our yards clay for 16 years now.
Think about some sort of sump pump in the event you have tons of rain.
Traditionally they are not dug deeper than the diggers shoulder, because of the risk of earth collapsing.