Cold Frame

It wasn't exactly life giving me lemons, but when someone asked us to throw out a piece of 48 x 60" plexi at work, I threw it in my car instead.  It took me a few months, but in December I picked up some pre-treated lumber, hinges and adhesive and made a cold frame.  I installed it under the stairs to the deck, on the concrete slab, where it gets good southern light midday.

Even with few plants in it, I could see that it was moist inside, and a few degrees warmer I hoped.

(Yes, I tend to have a rock pile around to provide materials for planting troughs.)

After the brutal deep freeze around New Years, I was finally able to work outside again last week.  Neighbor Ray and I added a layer of 1/4" hardware cloth to the bottom to keep out varmints, lined the  bottom and part of the sides with landscape fabric and poured in a couple hundred pounds of sand.  The sand should provide some thermal stability and insulation for the pots, while also acting as a moisture reservoir.  Any roots that escape their pots can run freely in the sand.

I cut two 2x4s to hold the lid open while we worked in it.  Into the cold frame went a couple rooted cuttings of my favorite lavender, a pot of cotoneaster franchetii cuttings, and some dormant first year vernonia noveboracensis.  Also into the mix went a few pots of seed like eryngium yuccifolium that need to be stratified.  I'm hoping that we can use the cold frame as a little nursery for germinating seed and growing on precious seedlings. With the lid closed the small pots will be safe from the never-ending squirrel inspections.

The cold frame should also function like an alpine house, keeping cold hardy but moisture averse plants like this delosperma happy throughout our wet winters.