A greenhouse is an ideal environment for growing fruits and vegetables. Not only are you able to keep out insect pests that wreak havoc on your growing plants and produce, but you also have the means to control the humidity levels. With control over water and humidity, you enable crops to flourish.
One question we get a lot is whether you can create a home greenhouse using tarps. Of course! Not only is it easy to maintain a greenhouse made from tarps, but you have the option of taking it down during the winter months if ice and heavy snow are problems in your area.
Find out what equipment you need to build a tarp greenhouse and the best ways to prevent mold and make sure the air is humid enough. It’s an easy project for any DIYer.
How to Build a Greenhouse Using Tarps
The first step to building a greenhouse using tarps is by considering your frame. A simple method is to purchase PVC piping and T brackets and create the frame you need. This creates an affordable, portable greenhouse that you can move around. If you want a more permanent frame, use 4 x 4” pressure-treated lumber for the posts and then 2 x 4” posts to form the roof joists.
You might also want to look into DIY EZ frame kits online and build your own structure. Garden supply stores also sell hoop-style greenhouse kits. Any of these works well and just need the tarp to go over the framing.
What you should consider is where you plan to keep the frame. If you purchase a metal frame kit, it may start to rust. If it’s exposed to rain and humidity, the lifespan may not be as much as you’d hope. PVC isn’t going to rust or degrade, but it may not be as strong in bitterly cold temperatures, so you should take it apart and bring it inside over the winter. Pressure-treated wood is strong and resists rot, so it’s a great choice if you can leave the frame up all year.
Once the frame is in place, stretch clear PVC tarps across the roofing and down the sides. Secure the tarps to the ground by securing stakes through the grommets. Use cabling to secure the tarp to the top of the frame.
You may need several tarps to form the roof and walls. That’s fine, but make sure you’ve stretched an entire tarp over the roof. If you use two, there is the risk of rain leaking in. It’s better to have one large tarp for the roof and secure the clear PVC tarps to the roofing using the grommets and cord to connect them. You may find on a smaller greenhouse that one oversize PVC tarp is enough to cover the roof and form the walls, too.
During the winter, if your greenhouse is coming down for storage, wash the clear PVC tarp to remove any grime. Let it dry completely and fold it up. Move it to mice-proof plastic storage bins to avoid damage while it’s stored in a shed, garage, or barn.
Tips for Controlling the Humidity and Keeping Plants Watered
A greenhouse made from tarps is cost-effective and works incredibly well. If you want to save additional money, there are ways to water your crops and keep everything aerated without having to spend a lot on energy and water bills. These tips also help if you’re not allowed to water gardens due to drought conditions.
For easy watering, consider punching holes into a hose and laying that along your plant beds. When you turn on the water or open up a valve to let water flow from a rain barrel, the water comes from the holes in the hose. You’re not wasting water as it goes exactly where you need it to go.
Do you live in an area where rainfall is sporadic? You may not be able to water plants from a garden hose or drip irrigation system. Instead, look into using the water from your washing machine. As long as you use a non-toxic, eco-friendly laundry detergent, it’s a great way to water crops without using up water from a well or public water system.
Remove the washing machine drain hose from the line that goes to the sewer or septic tank and put it into a bucket instead. Have a second bucket handy as one may not be enough, depending on the amount of water used by your specific machine.
Place a rain barrel in your tarp greenhouse. Pour the water you use to wash clothes into the rain barrel. When you need to water plants, use that recycled water. Most rain barrels have water spigots in place that you can attach a hose to. Gravity helps the water flow through the hose to your plants. You won’t need a pump to push the water from the rain barrel to the hose.
That’s a great way to recycle water while watering your plants. How do you have a humid environment without leading to mildew and mold? Make sure air flows around the greenhouse. Floor fans help with this. You’ll be surprised by how cost-effective this is when you purchase solar-powered fans. They’re not expensive, and all you need to do is attach the solar panel to a post that forms your greenhouse frame. Make sure there is a stand or table nearby to put the fans on.
How do you build humidity? When the sun warms the greenhouse, you just need to introduce moisture. The heat will cause water to start the evaporation process. If you’re using rain barrels and recycling your washing machine water, leave that barrel uncovered. That helps boost the humidity levels. You can also spray water onto the ground in the greenhouse and allow that to increase the greenhouse’s humidity levels.
If you have more extra funds in your greenhouse budget, you can purchase a greenhouse humidifier for your greenhouse. They may require electricity, so you’ll need a nearby outlet if you don’t purchase a solar-powered model. Many are easy to run. Fill the water tank with water, turn it on, and it runs until you shut it off. If the water level is too low, many have automatic shut-off to prevent damage to the system.
Chicago Canvas & Supply provides clear PVC tarps in sizes up to 10 x 12’. If that’s not large enough, we also have custom sizes available. The PVC tarps block UV rays, which you may think is a problem. Despite what you might think, this will not kill your growing plants. Plants need “Photosynthetically Active Radiation,” which is the blue and red wavelengths from the sunlight, not the UV rays.
Our clear PVC tarps are on sale, so it’s the perfect time to get the tarps you need for your outdoor greenhouse. At 20 mils thick, they’re going to withstand wind, hail, and strong winds, so don’t worry about poor durability. If you need hardware to hang the tarps from joists or PVC piping, talk to us about our support hardware options. fOrder clear PVC tarps online or request a sample by contacting our customer support team via live chat, email, or phone.