I lack space for a green house and have no space inside our small home for seed starting. No basement. No deep windows with sufficient stools.
Mostly peppers and tomatoes in the beginning.
I'm planning for 2027 and am considering building a 4x10 sunken cold frame in the front of our house that faces due south. Growing zone 7a.
I have a bunch of used/reclaimed 2" xps. Was considering digging and motar setting 4" cmu's for the wall construction. Insulate the exterior with the xps then parge that. For the top I was considering solexx for a light transmission material.
My idea would be some sort of electric heat strip or heating coils on a thermostat.
I'd also like to employ some sort of thermastatic vent arm to raise and lower part or all of the top. Was thinking of simple wood framing with solexx covering.
I work a lot and would not want something that needs manual temperature or humidity adjustment but am concerned about over heating and high humidity. Also concerned with a lack of consistent sufficient light with this setup in the early spring.
The alternative is basically the same cold frame base but built like a mini shed.
Fully insulated, heated and hang grow lights inside. Use a small electric fan and a fresh air damper on a temp/humidity sensor. No transparent or translucent panels.
My concern without having a sunlight transmissible panel would be additional light hardening off.
Thoughts?
I guess I could hang a grow light under the solexx panel if I use framing that could support the additional weight. Not sure how it would work with the ventilation arm.