Spent the day playing around with little bolts to put this together. Should extend my growing window by a month, won’t be able to extend end of season I think though.
A quick suggestion as those don't look like nylon lock nuts; grab yourself some medium strength locktite and put a drop on each of the threads otherwise that frame will slowly become loose due to thermal expansion/contraction cycling
Solo cup (or generic equivalent) starts! I do the same thing. Way cheaper than buying "gardening pots", but you do have to put holes in them.
I have a very cobbled together grow light getup for my starts, but have thought about trying to make an enclosure around one of my raised beds to get the temp up earlier and push the season out.
I've had mine going for three years and they seem to be holding up as well as the cheap poly grow pots, so woo. I keep my starts in a tray to keep the extra water and keep the bottoms moist if I miss a watering.
Also Canadian. I bet you can extend seasons depending on what you are trying to grow. A small cold frame would be beneficial for greens, brassicas and other cold weather crops. We grow these year round. When we were in the city I made some from some old pallets and a window I picked up in alleyway junk piles.