Our past couple of Mondays have been beautifully blue-sky clear and cold; waaay too nice to work indoors at a keyboard. Last week I got a wild hair to construct me some good old fashioned cold frames. After the spring of 2008 – which was more like a double dose of winter – I want the extra insurance against cold rain, bitter winds and late frost…and I’m talking last May!!!
I consider myself fairly resourceful. I also consider myself, uh, retentive. It’s not like I save string and nurture a giant rubber band ball, I’m just loathe to throw out something that might come in useful at some point in the next say, 50 years. I might be able to see the floor in our garage if it didn’t work out for the best so very often. Let’s just say if they ever have a household-repair Survivor series, I will NEVER get voted off the island. I even have a name for my disposition. I (proudly) refer to it as “Urban Hillbilly Chic”, and I’m sure it’s only a matter of time before I get my own line of lifestyle books, TV show, and attendant product line. Well, maybe not.
Anyway, as often happens when I get an itch to build something I start looking through our garage, carport and the scary, cobwebby room we blithely refer to as the “garden room”. Some of you may recognize the pieces of my cold frames as components of IKEA shelving units. Yep! It was like a cold frame kit once visualized with the right eyes. The old saying goes, the hardest piece to write is a set of instructions, but I’ll give it a go.
I made 2 frames but here are the directions for a single:
Position the 3 foot corner shelf pieces so that their longest side is down with the slanted end facing forward. Screw two corner shelf pieces at right angles, horizontally to two 4 foot lengths of upright supports at the back of the frame to provide a brace at top and bottom. Screw another 4 foot length across the front of the box to join the front edges of the frame. See?
Things were going along so well I was moved to paint (!!!) the boxes which will help them withstand contact with moisture and soil. Although frankly, these things have been in the “garden room”, believe me they’ve seen moisture and dirt. I think they look quite dapper in barn red.
I know what you’re thinking…this is the draftiest cold frame in the history of cultivated gardening. At this stage these frames would actually make good shade structures to protect young seedlings in the high heat of summer. Yes, we do get heat in July and August, which is when I should be seeding fall crops. Without cooling shade the tender sprouts and their shallow roots are destined to fry.
However, the heat of summer is a loooong ways off which is why I purchased rigid sheets of styrofoam insulation at the hardware store. I had to break down and visit the big orange box store because our last sheet of insulation was turned into a Sumerian temple about 5 years ago…note to self: spray paint dissolves styrofoam!
I cut the 4×3 foot sheet into pieces to line the frame. I choose to cut them a little on the large side so when I wedged them into place they would hold securely. A little duct tape on the raw edges and to finish the corners and ta-da! A fully insulated cold frame. I cut 4.5 mil plastic sheeting to the width of the frame and long enough to fully cover and extend beyond the front. Given our wierd artic weather pattern this year and the fact that I want to plant sooner rather than later, I doubled the plastic for extra protection. My thinking is this will trap the greatest amount of heat and quickly warm the soil. Once the season is underway I may have to make a second top with only a single thickness to allow more light to enter the frame. (but I doubt that I will)
I reinforced the edges of the plastic with duct tape and stapled it to another 4 foot length. This rests along the back of the frame. The plastic can be rolled out to cover the box, partially removed to vent the inside or completely rolled up and secured at the back of the box for maximum exposure.
I was supremely excited to discover that these sturdy, light-weight boxes can also be stacked to form double height frames to house my peppers and basil this summer; it really is quite ridiculous how cold it can remain around here until the 4th of July!
Given that winter is intent on impressing us this year – we had spitting snow again yesterday – I’m thinking I’ll get a lot of use out of these babies. I love it that they were almost FREE to construct; about $4 for the insulation and about $3 worth of plastic. I know my shivering plants will appreciate their snug new clubhouse!
Cold Frame: Consisting of a glass or clear plastic window hinged to an opaque bottomless box, a cold frame is placed directly over a part of the garden in effect creating an area of milder temperatures within. The hinged lid opens to allow you to work with your plants and provides ventilation as well as protects against cold when closed.
Amend the soil within the cold frame with compost and plenty of organic material to boost fertility and provide drainage. A cold frame is primarily in use during the fall, winter and early spring when the sun is at a lower angle. To capture the available light and heat, site the frame where it will receive full sun between 9am and 3pm with the long axis of the structure oriented east-west.
The addition of a 6 to 8 inch layer of horse, chicken or rabbit manure turns the cold frame into a “hotbed” warming the soil considerable as the manure ages, a boon in cold climates. Carefully monitor conditions within the cold frame to regulate temperature and humidity and water the plants as needed.
– From Growing Your Own Vegetables, Sasquatch Books, May 2009