Winter Gardening Experiment with Straw Mulch, Fabric Row Covers, Plastic Row Covers, & a DIY Greenhouse
Winter gardening is a gamble. No matter what you invest in, you are always taking a risk. Temperatures in our area vary widely, as evidenced by November. We have already had temperatures in the single digits, a good snow, and now the forecast shows a week of near 60 degree, rainy weather. A few weeks ago, we decided that a fluke cold snap was not going to take the winter garden while there was still the promise of warmer days. We have had success growing kale & carrots into December without any protection. However, with a forecast low of between 15-20 degrees for over a week, I knew even this tough crops would fail us. We decided to first take a low cost risk, and purchased 800ft of row covers, 100 metal hoops, 1000 fabric stakes and went to work covering our most important, and delicate crops. Cauliflower, Brussels Sprouts, Beets, and Mustard Greens were all covered with a 6-degree protection frost cloth. We started covering the broccoli, but ran out of cloth early in the row. I remembered that I had an extra roll of clear plastic on hand, and we used it to cover about 15ft of broccoli as an experiment of sorts. We staked the plastic down the same as the row cover fabric. It was decided that lettuce, Swiss Chard, and peas were not worth the cost of .56 cents per foot of the row cover. Peas also received no protection due to the nature of their growth making them difficult to cover. Kolhrabi , cabbage, and rutabaga were deemed strong enough to survive the cold without any help.
Lets look at the how the crops did, from least protected to most protected. First, Kohlrab (Superschmelz):
The kohlrabi looks exactly how it did going into the cold weather. No changes, and no protection. The cabbage looks great, though it has definitely ceased all growth. No changes, and no protection (Early Jersey Wakefield):
The rutabaga also looks really good. No changes, and no protection (Laurentian):
Peas quickly died as expected (Tall Telephone):
While I don't have any photos, the Swiss Chard is toast. Little piles of mush. The romaine lettuce is still living, but very ugly. The inner leaves are unharmed and could be picked as loose leaf lettuce, though this is a heading type (Parris Island Cos).
Kale (left) and carrots (right) were mulched heavily with straw.
Some carrot tops were left sticking out of the top of the straw. Here is what the 2 weeks of very cold weather did them:
Thoroughly dead, and very mushy. They look a little green, but look at the center stem which is very brown. This week we finally had a few pretty days, so we raked back the mulch. Here are the results of the protection:
A nice bright, vivid green....though, very thirsty for light! They have crunchy stems and are growing nicely. We took the straw off for 2 days to recharge them, and have put it back on for 2 days, at which point we will remove it for the foreseeable future (60 degree days 40 degree nights in the 10 day). There are at least 5 heirloom varieties. Here is the kale:
It did just fine. Some of the bigger leaves that were left exposed have died and are turning brown. However, the inner crown where all of the growth comes from is a good green color with bright purple stems. This is also the part of the plant that we heavily mulched. It looks as if the plant actually grew quite a bit, even during the cold. We can tell because we had recently harvested all of the baby leaves. As you can see in the photo, some are ready to pick again. The variety is Russian Red/Ragged Jack.
All other plants received the 6-degree cloth row covers. The results were overall very good. The investment was a wise one. Here are the beets (Chioggia & Detroit Dark Red):
Greens look great, roots are still sizing up. We will have to wait to see if the warm weather helps size the roots, otherwise they will make delicious pickled beets. Here is the cauliflower, the most tender of the plants we covered. It was a tough choice deciding what plants got protected, and cauliflower almost got the axe, as it seemed destined for death with the temps we were expecting.
It turned out to be a wise decision. The plants look healthy and strong. No dead leaves. You can see some evidence of damage on the head, indicated by the brown mushy area near the top. The variety is Snowball Self-Blanching. The mustard greens not only pulled through, but put on a decent amount of growth. Before being covered these plants were cut back to the base:
I saved broccoli for last, because it is what inspired us to build the greenhouse. First, some photos of completely unprotected broccoli:
It is completely dead. It looks like the head and some sprouts on the main stalk are still living, but nothing can be expected of the unprotected broccoli. Like I said in the beginning of this post, I ran out of fabric before covering the broccoli. We cut broccoli from the list for row covers because it was the cold hardiest of all that we really wanted to save. But, I did manage to cover a short section in clear plastic like you would find at your hardware store. Here are the results of those plants:
Not only did they survive, but they thrived. They have grown substantially, and are all producing heads. The variety is Calabrese. After seeing the results of the plastic protected broccoli, we decided to build a larger version. I found plans online for a 12'x30' quick set-up DIY greenhouse. It was portable, and most importantly affordable. We wanted a little more room for experimenting this winter, so we opted to increase the size to 12'x60'. We ended up with this.
Temperatures from the first day:
The low was at 8am and was 28.4F. To see how fast the greenhouse heats, one hour later, at 9:00 AM the temps were:
This greenhouse will be used for baby kale and leaf lettuce. Hopefully, it will produce about 20-30 lbs of both each week.
Next week, I will post the detailed plans for the greenhouse, as well as a quick update on how everything is growing within the various phases of protection.