How to Build Your Own Polytunnel
Polytunnels are useful for all kinds of gardening requirements you may have. In an extended growing season they can help you save significant amounts of money, making them valuable for you and your garden. However it’s important to bear in mind that even though polytunnels may be rather cheaper than greenhouses considering the equivalent growing area they cover, they still come with a price attached. There are ways that you can go ahead and build your very own polytunnel from scratch with very basic parts that you can source easily and at a low cost. Here is our guide to doing just that.
The two main parts of any polytunnel are its tunnel framework and its polythene cover. There are various places you can go to look for a suitable long-lasting cover, and these are easy and affordable to find. The framework itself is the trickier part that you’ll have to get stuck into as your new DIY project. A normal polytunnel framework is made out of hoops of aluminium tubing. If you don’t use aluminium you can of course use a similar metal. You can replicate this using offcuts of scaffolding tubes and mains water pipes, both of which you may be able to find free of charge at a building site, or which you can purchase at a very low cost nearby. A typical scaffolding pole of 48mm outside diameter should be cut to a length of around six foot, and then driven into the ground to a depth of around three foot, sticking up out of the ground. This leaves three feet out of the ground to give you a polytunnel with three foot high straight sides. To prevent the tube from getting damaged you should use a heavy hammer with a block of wood on top. Using a spirit level will also help you to make sure that the poles are vertical. Then once that is done you can cut your mains water pipe of 50mm inside diameter long enough that when each end is pushed over a scaffolding pole it forms an apex at around eight feet above ground. You can then cut the remaining pipes to an identical length.
Keeping It SafeIt’s important to make sure the water pipe is safe and secure, and to do so you must drill a hole through the pipe and scaffolding tube and then secure it using a nut and bolt. Or you can simply put a large nail through the hole, cut off all but the last inch, then bend the rest around to the inside of the polytunnel. The polytunnel cover meanwhile won’t come into contact with any metal, so you don’t need to use polytunnel hot spot tape. To finish the job, position your hoops at intervals of four to five feet along the length of the polytunnel in order to hold the component parts of your polytunnel securely in place. Then you can leave it in position in your garden and enjoy the benefits it brings.