If you could extend your garden to last year round, or even a few months longer than before, would you do it? Are you interested in pushing the limits of your garden and your growing zone to see how many extra weeks of harvests you can squeeze out of your garden? If you’re interested in trying new things then you’ll love what season extenders can do for you.
There are a few specific benefits that you can get from season extenders. The first is the most obvious; they can extend your growing season so you can start earlier in the spring and continue gardening later into the fall. Another benefit is that they can give your heat loving plants a boost in the spring and summer by increasing the temperatures to where they prefer to grow. This means you can garden for longer, and see bigger harvests than someone who isn’t using one.
Many people equate greenhouses or caterpillar tunnels as tools that only farmers can use, and aren’t practical for home gardening. However it’s actually simple to make your own extenders and you can use them on raised beds, in ground gardens and even in containers. These items work for any type of garden, so why not give it a try.
Cold frames are essentially mini, unheated greenhouses. They trap in the warmth from the day and slowly release it overnight. You can buy cold frames from a garden centre and these are often made of clear plastic or glass, or you can make one using wood and an old window.
Cold frames are great because they are easy to move around, are simple to use and are effective. If you have a sunny spot on the side of your house, setting up a cold frame against the wall will increase the temperature even more, making them more effective.
The downfall with cold frames is that the height of your plants is limited to the height of the frame, and you have to manually open them on hot days to make sure they don’t overheat. Just for perspective, in the summer I would use my cold frames as a solar dehydrator and I would dry tomatoes in mine. It easily got to 40°C inside, so it’s important to air them out.
Cold frames are super simple to build out of wood and an old window. Wood framed windows are the easiest to use compared to the new vinyl windows. Check on Marketplace or at a used construction store (like Habitat’s Restore) to save even more money. Once you have the window you can determine what size frame you need to build – just be mindful of the angle of your frame that it still fits the window. You will need some tools in order to build this, including a power drill and a hand saw, but with a few cuts, screws and hinges you can build your own cold frame!
Hoop houses are the home gardeners take on farmers caterpillar tunnels. Many garden stores sell kits for hoop houses so they are easy to buy and set up. Similar to cold frames, these are unheated greenhouses that protect your plants from cold nights and frost, while warming up the air quicker during the day.
Because these are unheated, and not perfectly sealed, they won’t hold in much heat overnight. If your overnight temperatures are below freezing, it will still be below freezing in your hoop house. What hoop houses are good for is reducing the amount of hours spent at freezing temperatures and they eliminate the risk of frost on your plants.
Hoop houses can extend your spring garden so you can start weeks before your last frost date. If you keep them covered all day they will stay warm and produce fresh greens much earlier than expected. When I was gardening in Canada Zone 6 I would set up my hoop houses on April 1 (about 6 weeks before my last frost date) and I was able to grow a wide selection of plants!
Finally, hoop houses are a great way to protect your fall harvests during the cold nights and when frost warnings are in place. This means that your garden isn’t done when the tomatoes are harvested, but you can keep going with all the cold season crops!
Here in Canada we have way less selection than in America, which means we have to be creative with our gardening tools. Often times I see the coolest setups on a video but when I go to look for those products in my local store, I realize that they are only available in America. PVC hoop houses is one of those things. We do have access to flexible piping, however ours comes in a roll and not in straight pipes (although I haven’t checked recently if that’s changed. Please email me if it has!)
This makes using PVC piping a little more difficult because you have to change the shape of a rolled up piping to suit your garden. When looking for PVC piping, the flexible type is called Pex Piping. In addition to the flexible piping, you need to get a roll of vapour barrier. We use 6mil poly here, as it’s strong but still lets in light. Finally, on Amazon or at some greenhouse stores you can get greenhouse clips (in the last photo) that will attach the poly to the pex pipe. If your pipe is 3/4″, make sure to get greenhouse clamps that are also 3/4″ to fit your piping properly.
Once you cut your piping to shape you want to place it at each end of your garden and every 2 feet in between. Then you attach the poly! It’s as simple as that.
Okay, I know the above picture isn’t a real greenhouse, but it was the closest I could get. I use this for hardening off seedlings and it does an amazing job!
There are two types of greenhouses out there, heated and unheated ones. Most home gardeners are going to have an unheated greenhouses. And from there, you can either get a glass greenhouse or a plastic one. There are plastic ones that cover a shelf (like the photo above) or they can be an entire shed size. Glass greenhouses will be the size of sheds or larger and have a higher price point.
A greenhouse is nearly every gardeners dream. These spaces are perfect for seed starting, growing seedlings and keeping tropical plants in the summer. Because most greenhouses are unheated, you won’t be able to grow much in them over the winter, however you can try! There are ways to create passive heat in your greenhouse (which is outside of the context of this article) but it is a possibility.
There are a couple different ways you can use your greenhouse. Unheated greenhouses are a great space for starting from seed and potting up plants. However you can also use your greenhouse to grow heat loving plants like peppers, eggplants, cucumbers or tomatoes. With a greenhouse you can plant them slightly earlier in the season, have them grow really well all summer, and extend their harvest into the fall.
Comparing greenhouses with hoop houses and cold frames, greenhouses are often better for starting seedlings in rather than growing large amounts of food. If you want to extend your garden earlier or later into the season a cold frame or hoop house will do a better job since they are moveable and can be built to any shape to cover your plants.
There are small greenhouses on the market which are often shelves covered in plastic or step in greenhouses that only have a foot or two of space. These are similar to the photo above. I built mine out of an old shelf and attached a door on it. I loved using this for hardening off seedlings and moving them outdoors sooner. If you place your mini greenhouse against an exterior wall of your house it will stay warmer for longer, taking the heat the house is giving off. These type of greenhouses work best for getting your seedlings outside sooner.
Okay finally, on the untraditional side, there are different tools laying around that you can use as season extenders, although they aren’t as permanent and may not be as effective. The first is covering your plants with a bucket if it can fit under it. This is best when there are cold nights and warm days ahead.
I like to build structures and attach poly to them making them a moveable greenhouse. I like using this for hardening off plants. In the photo above I have my cool season crops outside uncovered, with my heat loving plants under the greenhouse. This helps harden them off sooner, so if the weather turns for the better I can get them out as soon as possible.
Play around, have fun, experiment and see how far you can push the limits of gardening. In my opinion, that’s one of the best parts about gardening.
Gardening Advice for Short Season Gardeners
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