Catching Some of The Heat

With the pots of tomatoes on the heatmat, I try and reduce the heat loss at night, as this setup is all in an outside hothouse and it gets terribly cold in there on these frosty nights. What I came up with, was to cover the seedlings with a sheet at night, but I needed to keep the sheet away, so came up with this idea.

Using collapsible bulb type crates, I tied up the ends so they didn't drop down and they fit across the pots and onto the lip of the heatmat, sort of perfect as it lets the warm air out, but seems to still hold plenty of warmth so the seedlings don't get effected by the cold.

Look here to see what it looks like when covered for the night.