cold season plant thinking

Rather than steal the thread about the 2x3 plastic mixing tubs, I thought I would start this one.

If those tubs are alright/safe for planting garden plants in,,,,,,what if you had a 55 gal barrel filled with a liquid that would not freeze and the outside painted flat black. Then have a box built to fit on the top of the barrels and hold the mixing tubs. You could have hoops on top of the boxes with plastic over the top and down the sides. This could be done early spring. As the days get warmer, cover the sides of the barrels with plywood or something to shade them so they would not gather heat. Later, remove the plastic from the hoops as temps get warm enough to not needing protection. Then as we enter the fall season, uncover the barrels, then later bring out the hoops and plastic for the hoops and barrels. I suppose this thing would look like thunder, but would it work?

I just gotta build something for the off seasons. This cold weather is just really getting to me. I really have cabin fever bad, can ya tell? Needing to get out and start scratching in the dirt and start planting!

It depends if you heat the liquid . If you add antifreeze the liquid will still take on the outside temperature so could drop to well below freezing point and not freeze .

I have heated beds one in the glasshouse as 2 inch of play sand on top of two off 2x2 foot x 2 inch thick concrete paving slabs , lay in a heat cable ( 40 watts per metre /yard ) and thermostat add two more inches of sand then grow in a top layer of three inches to four inches of MM .

You could follow that idea make the boxes deeper to get six inches or more of MM and also to put a covering over the trays to help retain heat.

My seed propagation bed is indoors not in the glashouse has a 2 inch thick layer of styrofoam set on a table , pond liner , 2 inch sand , cable & stat ,2 inch sand then a covering of pond liner to keep the sand moist and retain the heat ..I just sit my seed trays on top and pull the LED full spectrum UV light down .

A combination of the bed ideas could give you an insulated base on a strong bed , sand , cable & stat , sand & a pond liner , then on to six or so inches of MM to play with , plus a top cover over the whole bed .

You would only need to set it at just above freezing if you have got the seeds to germinate and have started them growing as a plants. It would be cheaper than heating a barrel of liquid to stop it freezing.