Cold Frames/Hot Bed

Does anyone use cold frames or hot beds for either growing or starting seeds? Twice a year I get the urge to try one in the spring and fall. Then summer comes and I forget about it. Are there any cons and would they be worth it?

Hey Travis. At my old place I built a couple cold frames. I used them for acclimating fig cuttings and starting seeds then as beds for summer annuals. Definitely use either the corrugated plastic (like tuftex) or polycarbonate as trying to reuse glass windows will just mean picking glass out of your soil eventually. I’m not sure if you could keep them above freezing passively in the spring with say foam board insulation over the glazing–that was something that always informed my use.


I replaced my garage man door (with a window) with a new fire rated door (without a window) this summer. I have been meaning to cut the old door basically in half, build up a couple of scrap 2x10s I have, and retrofit the hinges from the door to turn the old window into a cold frame “lid”. Sure it will be heavy, but I am young enough and may try to source some sort of air springs to assist with the operation. I’d likely use it for lettuce/spinach etc to keep stuff alive most of the winter and extend the picking season.

I purchased a book called the Winter Harvest Handbook which should have what you are looking for. The main takeaway I’ve had from that book is that you are basically extending your harvest period, not necessarily trying to get new growth during the winter. It’s like hitting the pause button on having your veggies wilt and die.

1 Like

If I built another one I’d probably add an automatic vent opener too.

1 Like

I built and used a traditional hotbed using straw horse manure bedding. It is an awesome system and worked great. I used an insulated concrete workers blanket over it at night.

Right now I’m thinking it might work well to start broccoli and cabbage instead of taking up space inside. I’m not sure how much those soil warming cables use for electricity but that might be an option. That’s a good point about broken glass.

Unfortunately I don’t have a reliable source of manure right now.

I do a tent and some frost cloth for spring and fall have already started eating micro greens got some radishes on the way

I think I’m going to put some flats under a low tunnel this week. We have some lows in the high teens later in the week, but after that looks pretty good.

Anyone else trying to grow some greens this fall/winter in a cold frame or hot bed.

Mine is simply a bed on the south side of my home… gets all day sun… slopes to the south some, is at the base of a large brick wall… has a bent cattle panel frame over it to support some floating row cover when needed.

Right now no cover needed so i have it pulled back.

My leaf luttuce is doing pretty good so far.


1 Like