Year-round Uses for A Cold Climate Greenhouse

– Posted in: Hardscaping and Projects, How-to, Seeds and Seed Starting

(Editor’s note: Neil Moran wrote North Country Gardening seven years before Cold Climate Gardening got started. I asked him to share what he’s learned since building his greenhouse.)

Neil Moran Christmas greenhouse in snow

Photo by Neil Moran

As you all know, the summers are sweet, but short here in the North. It seems not long after we’ve sown our vegetable crops and put out the hanging baskets, the days are getting shorter again and it’s time to clean the leaves out of the gutters and put away the garden tools for winter.

With the thought of extending our short growing season, I built a modest-sized greenhouse and equipped it with a wall-mounted gas heater. The idea was to lengthen the season on the front end by doing what most folks do with a greenhouse– start a few plants from seed.
Much to my delight it has turned out to be much more than a place to start a few transplants.

Neil Moran watering seedlings in a greenhouse

Starting seedlings was the main reason to get a greenhouse. Photo by Neil Moran

The first couple of years I used it solely for the purpose of seeding tomatoes, peppers and some flowers. It allowed me to start getting outdoors to “garden” towards the end of March, instead of late April or even into May. Then, gradually I started thinking of other garden-related things I could do in the greenhouse. The first thing that came to mind was using it to make holiday wreaths and centerpieces, which I had been doing in my garage. This meant I could start working in the greenhouse in early November and finish up just before Christmas.

Neil Moran Wreath making in greenhouse

Making wreaths in the greenhouse. Photo by Neil Moran.

About late February the next year, when cabin fever became unbearable, but the sun was shining nicely and water was dripping off the icicles that formed under the gutters, I realized it wasn’t too bad out in the greenhouse. In fact, the sun beating down through the woven poly actually heated the greenhouse up to about 70 degrees. The heat penetrated every fiber of my being, unlike the intermittent heat from the gas furnace in my house. With this thought in mind I decided to hustle the house plants out for a little re-potting and TLC (I think houseplants can get cabin fever too!)?

So now I was utilizing the greenhouse starting in February through to June, and then back in it in early November to make my holiday fare. I began to consciously think it would be nice to utilize the greenhouse each month of the year, if possible. So to use it all summer I started lettuce in window-box type containers in late June and set them under a bench in the greenhouse so they wouldn’t get too much sun. I also grew a few tomatoes and peppers in pots inside the greenhouse, trying my best to water them every day. I installed an overhead fan for air circulation and covered the poly with a dark shade cloth so it didn’t get too hot inside. A misting system installed to root cuttings helps to further reduce the heat in the greenhouse and provide a more humid environment, while giving me one more thing to do in the greenhouse during the summer months.

So now the only period during the year I wasn’t in the greenhouse was late August until about late October. A good harvest of rough neck garlic gave me an idea. Why not dry the garlic in the house starting in late summer and bring in a few things, like pumpkins and squash that might succumb to a frost if left out in the garden. The culinary aroma of the garlic in the greenhouse mixed in with the garden produce had me thinking another thought: why not add to the mix of garden aromas by picking some herbs and hanging them in the greenhouse? So I hung bunches of oregano, sage and basil from the cross bars. I don’t think an Italian kitchen could smell better! I also hung flowers to dry that I pick from the garden and some wild places near my home.

Neil Moran Herb drying in a greenhouse

Drying herbs in a greenhouse puts what would be considered a disadvantage to good use. Photo by Neil Moran.

Since I quit my day job and started freelance writing full-time I have a little more time on my hands. I’ve started doing something I’ve wanted to do for a long time but never seemed to have time to do before: harvest and dry the seeds of native trees, shrubs, heirlooms and wildflowers. I now enjoy relaxing in the greenhouse in September and early October as I sort through my seed harvest. If I’m so inclined, I’ll write a few lines.

You southern gardeners may not appreciate this, but anytime you can sit outside in chilly October or March, albeit in a closed-in (transparent) structure like a greenhouse, and not shiver is a real bonus. This is what I can look forward to now that I’ve found additional uses for my greenhouse.

So there it is. It is possible to garden just about year-round, even here in the chilly north. Okay, it may not be like gardening in sunny Orlando, but it sure gives me more time to enjoy my favorite past time.

How do you cold climate gardeners extend the season with your greenhouse?

About the Author

Neil Moran is a horticulturist and freelance writer. Besides garden articles, Neil writes blogs and other such things for the green industry.

Comments on this entry are closed.

antjon December 26, 2012, 1:11 pm

I have only a small greenhouse which i have just lined out with fleece, i have a small t/stat controlled fan heater so as to keep a stable temp and get an early start with seed sowing, but after reading your post my greenhouse will become my second home i am retired and have time on my hands , thanks for the ideas.

Mary in Vermont October 7, 2012, 10:44 am

I’ve had an unheated greenhouse for about 9 years in my zone 3 climate. I can put cucumbers and tomatoes in it, covered with remay, about a month earlier than I put them outside. I use it heavily in the summer for cucumbers, peppers and tomatoes, the latter of which do much better than they do outside. Also start lettuce there in early April and again in mid-August for fall, and over-winter spinach there; I plant some on September 1 and more on October 1, and have great crops in the spring.

Bev September 27, 2012, 6:57 pm

I too live in a cold climate, in the mountains of Montana. I also have a green house. I plant lettuce and spinach in it in the early fall and had lettuce all the way to Christmas. During the summer I grow my beans, zuchs, peppers, cukes, and squash in the greenhouse. We get a frost here almost every month of the year. This year we had a frost on July 4th. There went the spuds.

Julie September 13, 2012, 4:28 pm

Even though I’m in Upstate SC, I love my greenhouses. My first greenhouse was a birthday gift from my hubby. Actually, I think it was a bit self-serving: he was tired of all the lights and seed-starting in the basement! 😉 The second greenhouse was purchased for my heirloom plant business–a commercial structure on our suburban property by the river. It was a beast to construct–I think our children, had they been nearby, would have learned a lot of new words while we put it together! Still–I love being out in the greenhouse in January and February. We don’t have the big snows that you do, but it’s such a pleasure on a chilly day. And–there’s nothing I love more than working in the greenhouse during a storm. This winter, I’m attempting to grow produce for our family in the greenhouse along with the seedlings. We’ll see how it goes! The only thing I haven’t been able to start successfully are the seedlings for fall. Even with the shade cloth and fans, it’s still too hot to germinate lettuce. (I cooked all of the seeds, unfortunately.) Lovely article, and I wish you much joy in your greenhouse!

Neil Moran September 14, 2012, 2:14 pm

Hi Julie, sounds like your greenhouse has evolved like mine has. I’ve been thinking about starting some fall lettuce, it is cool here in the fall. I know people in this area who keep greens gong all winter by covering the greens with poly inside the greenhouse. On sunny days it grows a bit, they cut it, it grows some more. You may want to start your seeds a little later in the fall (?). Best wishes and good luck with your greenhouse!

Pat Webster September 13, 2012, 3:46 pm

This is an inspirational post. Like you, initially I used the greenhouse to start seeds, both flowers and vegetables. I open it in late March/early April since our winters are longer and more severe than yours (or so I think) but haven’t had the time or energy to use it otherwise. Now I may. Thanks for the ideas and the encouragement.

Neil Moran September 14, 2012, 2:16 pm

Hi Pat, I like it, “inspirational.” I think that’s what gardening is all about. I’m glad my article will you inspire you to explore some more uses for your greenhouse. I just enjoy being out there, soft music playing or the sound of the birds chirping. Best wishes.

Dee Sewell September 12, 2012, 3:50 pm

Lovely post. We have a polytunnel here in Ireland and our winters aren’t generally as extreme as yours. I try and overwinter some crops however. Bean, carrots, perpetual spinach to name a few. Like the idea of the dried flowers hanging 🙂

Deirdre in Seattle September 12, 2012, 3:28 pm

My greenhouse is much smaller than yours, I got it to winter over my borderline hardy plants (In pots). It’s also flimsier than yours. It didn’t retain heat well, so I put winter weight row cover over it. In summer, it is perfect for my orchids and epiphytic cacti. Watering with the hose is much easier than watering in the house, and the orchids need the cool night temperatures for bud set. I bring in the houseplants at the end of September.