Ahhh the wonder of discovering yet more season extension in our vegetable gardens in frigid
growing zone 6a! In previous years, i had grown salad in the basement under lights, and sometimes with a heat device below the flats or pots. Now, this is more like it!

The last few nights have seen temps falling to -3*F., and i wondered if my cold frame experiment would be done for the season. Today, a balmy 38*F, had me investigating with camera in hand.
YEEEHAW! We still have several looseleaf lettuces and cilantros looking very good in there, AND there are even some Parsley and Nigella (Love in a Mist) that have germinated from the compost therein!! This calls for more of the same, and i will be extending the coldframe/salad bed by 3X after seeing it work so well. Here in Kentucky, it rarely gets much colder than this - so success is assured barring unforeseen coldness ( such as the oldtimes tell about this area - it HAS warmed up 'round here!).

To have salad in YOUR winter garden, here is a list of materials needed, and some options to use your coldframe with more controls over what Mom Nature throws at us all (Bless her heart!).
btw - did you know that in these mountains, you can say anything about anyone - as long as you follow it with "Bless His/Her heart"?? I love the blessing of it!).

Materials Used:

1. 6 bales of STRAW (not hay - this holds up better, and contains few-to-no weed seedheads)
2. 6 mil Black Plastic sheeting
3. a coil of 9 guage galvanized wire - to make garden staples, or buy some ready made
4. a bale of soiless seed starting mix
5. a small pile of either your precious homemade compost, or some bought in bags
6. a couple of old glass storm doors or window
7. an old comforter or blanket for insulation on very cold nights.

Lay your bales in a rectangle, where you want this to remain. I chose a very slightly sloping spot, so my bed would be lower on the south side, and receive a bit more light and good drainage. I do not think this matters too much!
Next, i covered the bales with the plastic sheeting for two reasons: heat absorption with black plastic AND to preserve my straw bales longer in our sometimes rainforest climate. When we are done with these, there is always a great used for composting straw, as mulch or even to grow a summer salad bed on ( more on this in another blog, so keep coming back!). The plastic goes all the way to the ground, and is just attached with your pins ( around 6"-9"long, U-shape).
i put newsprint very thick in the bottom, but not necessary. Follow this with most of the bale of soiles mix, well-moistened. Top with your compost and remainder of soiless mix, and stir around to mix. Top with your storm doors or windows. The comforter or blanket is just for very cold nights.

As seasons change, one must be vigilant as to the temps heating up too much under the glass (or plexiglass). You can have an optional thermometer in there, or even a remote one from your house! Also, there are automatic openers for when it becomes too hot.

One can also buy a soil heating cable to snake around underground about 4-6" deep, allowing for germination of many plants that require bottom heat. You can grow alot of transplants in small spaces for the home garden.... and this would pay for itself quite rapidly in plants you no longer must buy from others.