Using cold frames is one of my favorite ways to extend the growing season here at Happy Acres. I’ve been using cold frames for a long time, and the design has changed as my needs and intended use for them has changed. Before I had a greenhouse I used cold frames to grow and harden off seedlings. These days I use them for protection from the weather and from critters like deer that would otherwise eat everything I planted. You can read about how I made the current version I’m using in my 2011 post on Cold Frames. There are a lot of good designs out there for cold frames, but these have suited my needs the last few years.
I have four cold frames that I built, and they are situated down along the east side of my greenhouse. They are each about 4×4 feet square, and made out of untreated lumber. The first one was planted with 30 lettuce plants back in late October, and the varieties include Baby Oakleaf, Jester, Outstanding, Tango, Simpson Elite and Red Sails.
All of the plants have leaves big enough to eat now, but I am trying to let them size up a bit more before I begin harvesting them. That’s Simpson Elite in the above photo, one of my favorite green leaf lettuces. The leaves are thin and tender, and it is great for salad and sandwich use. It is also my favorite lettuce to use for a Wilted Lettuce Salad.
The second cold frame bed is planted in arugula and spinach. Some of the arugula has been there since summer, and I have let it grow on while the fall plantings size up. In the above photo you can see the older Apollo arugula plants in the middle, flanked by a new planting of Speedy arugula on the left and Viroflay spinach on the right.
The third cold frame bed is planted with a mix of the old and the new. Winter Density is a mini-romaine lettuce I’ve grown for years, and it’s joined by a couple of varieties from Fedco called Winter Marvel and Red-Tinged Winter I’m trying for the first time. Both of these are touted as good for over-wintering. On the far right in that bed is White Russian kale, which I want to test for its winter hardiness. This bed was planted in late November. I got them out later than I had planned, and the plants are still quite small.
Something else new for me are the two Brassica carinata cultivars called Highland Kale and Amara Mustard, which I’m also growing in the greenhouse. They are in the middle of the third bed, and have grown quite fast since they were planted. Now we will see how hardy they are.
The fourth cold frame bed is planted entirely to spinach. And you can see in the above photo there is a nice stand of weeds growing in there too. I decided not to mulch when I planted, since the seedlings were so small, and the chickweed and dead nettle seized the opportunity to sprout up too. After trying a number of different spinach varieties for over-wintering, I have settled on three for this year. I am growing the o/p Giant Winter and Monstrueux De Viroflay, plus the hybrid Space. Giant Winter does very well for me as an over-wintered crop, though it does bolt fairly early come spring. Viroflay was the last to bolt for me this spring, and the large leaves make it productive too.
Giant Winter is the fastest growing of the three, growing even faster than the hybrid Space so far. I think these leaves will be ready for a salad soon. While the veggies in the cold frames are doing great, a couple of the cold frames themselves are literally falling apart. Cold frames #1 and #2 have been in use for at least six seasons now, and are badly in need of replacement. That will be on my list of chores for early next year. The other two were built a year or so later, and are holding together – at least for the moment! The below photo shows the deterioration of the wood at one of the corners of cold frame #2. It is safe to say I should have replaced them this year, but it’s too late now.
I hope you have enjoyed this look at how the cold frame veggies are doing here in December. I’ll be back soon with more happenings from Happy Acres.
Thanks for the tour, it was very interesting and informative as usual. The cold frames seem to be a really effective way for you to get some good harvests of winter greens.
Look how big that spinach is – mine is about half that size right now, but I’ve covered it with straw as I’m hoping it will give me a harvest come spring. Do you plan to harvest all of the crops in your cold frames over the winter or are some of them intended for an early spring harvest?
It will hopefully be a mix of winter and early spring harvests. Much will depend on the weather, and of course how the plants hold up. Much of the lettuce and arugula should be ready soon, and some of the spinach is headed for a salad in a few days. But most of the spinach will be used in spring.
My garden is very small and when the sun’s arc lowers in winter, it is shaded except for maybe 2 hours. Does a cold frame need full sun?
Hi Marie, most greens like lettuce and spinach don’t need full sun, though it will usually speed up their growth. My cold frames are lucky to get 3-4 hours of sun this time of year, and the greens do quite well there.
I would really like to try cold frames some time, but I think I’ll wait until I get everything else I’m doing stabilized! You sure have some nice looking greens right now.
Your winter salads look better than the ones we sowed in our cold greenhouse. I think we need to go back to the drawing board.
Some of my raised beds are like your coldframes – I mean in terms of the condition of the wood. I’m planning a major replacement programme for next Spring!
Wish I could have cold frames but I have no place at home and the community garden plot would require snow shoe access come winter. It’s good to hear you get some growth during the winter, that would be my other concern given our latitude. Of course, as warm as this winter has been so far, I could still be gardening in open beds except for some killing freezes.