18 Super Cheap DIY Greenhouse Ideas for Your Garden - Backyard Boss
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18 Super Cheap DIY Greenhouse Ideas for Your Garden

Greenhouses are one of the best garden updates to have for your plants. Unfortunately, they’re also quite pricey. Commissioning a functional greenhouse for your plants will cost you at least a few hundred dollars and even then, it might not be the design you were going for. But greenhouses don’t have to eat up your savings— just build them yourself to protect your potted plants and flowers from cold weather, rain, and wind! Here’s a list of 18 super cheap DIY greenhouse ideas that use a variety of materials and designs to build their dream garden enclosure at a fraction of the normal price!

1. Excess Reno Greenhouse

Excess Reno Greenhouse
Image Credit: mwhite30 via Instructables

If you’ve recently gone through renovations, this small, but sturdy greenhouse project is a fantastic way to use up any excess reno materials you have. Without the use of any heavy framework, this wooden greenhouse has a lightly stained vintage wood door, large glass window walls, interior wood paneling, standing seam metal exteriors, and transparent corrugated plastic roofing. Even if you don’t have everything on hand, as long as you have enough old windows for a wall, the rest can be bought at a low cost. Follow this tutorial for a detailed step-by-step process on how to build a greenhouse for your plants.

2. Polycarb and Pine

Polycarb and Pine
Image Credit: orndorff6kenzie via Instructables

This mini greenhouse is made mostly with wood boards and corrugated plastic panels. It’s a simple construction that doesn’t require much woodworking skill and money to complete. Specifically, they built a sturdy wood frame, used OSB to board up the walls, added poly carb roof panels, and cleaned up its exterior with pinewood boards for bonus curb appeal. It’s neat, easy on the eyes, and great for simple greenhouse gardens!

3. Large but low Cost

Large but low Cost greenhouse
Image Credit: Paul Mellia via Instructables

This larger greenhouse is built with a tunnel-like structure that can house countless plants and give you more room without eating up your budget. The key to this low-cost polytunnel barn-shaped greenhouse project is to recycle old building materials from local businesses. By approaching small businesses to buy their excess or second-hand scrap materials, you can save some coins while helping the local market.

4. Recycled Pallet Enclosure

Recycled Pallet Enclosure
Image Credit: dparker1980 via Instructables

Pallets are one of the most loved materials for recycled DIY projects. This time, you can use them to build a gorgeous amazing greenhouse. Make sure you get a good number of old pallets and separate each wood plank carefully— don’t leave behind any nails or jagged edges! For a fun design element, use your excess pallet wood planks as colorful exterior fencing to make your beautiful greenhouse pop!

5. Leaning Greenhouse

Leaning Greenhouse
Image Credit: Organikmechanic via Instructables

This type of greenhouse is called a leaning greenhouse since it shares one of its walls with another structure. It’s similar to a sunroom and an enclosed veranda, especially if your greenhouse will share a wall with your main house. This extends your house with a classy garden boutique that’s just a few steps away from your living room. This is built with recuperated wood and old glass windows.

6. Easy Domes 

Greenhouse Easy Domes
Image Credit: rickharris via Instructables

Although this geodome greenhouse looks modern and expensive, it can actually be done at a very low cost! What matters here is to put in the hard work you need to build a sturdy dome-shaped greenhouse for your plants. These inexpensive greenhouses make a wonderful statement in your backyard and can be made using wood struts and cling film for plastic cover. If you want something more permanent, transparent sheets or poly sheeting will be a smart alternative to protect your plants from rain and wind.

7. Recycled Glasshouse

Recycled Glasshouse
Image Credit: LoriH99 via Instructables

A greenhouse sometimes also gets called a glasshouse— and this DIY tutorial with detailed instructions took this name to heart! This lovely greenhouse is made out of a matching set of old unused windows which, when put together, make a simple yet striking yard feature. The size, shape, and dimensions of your greenhouse all depend on how many window frames you have. By doing this, your greenhouse garden gets a healthy dose of sun.

8. Repurposed Carport

Repurposed Carport
Image Credit: lynne123 via Instructables

If you have an old carport or shed wasting away on your property, this is the perfect chance to give them a new purpose. This tutorial cleverly teaches you how to transform an existing structure into a functional greenhouse for your plants. Since you already have something to build off from and if you opt for repurposed materials, your costs are minimized. All you need is enough wood for your frame, a heavy-duty plastic sheet, and some basic carpentry skill to get it done.

9. Miniature Greenhouse

Miniature Greenhouse
Image Credit: beaskywalk via Instructables

In case you want a perfect greenhouse but don’t have the space for a large walk-in, check out these mini self-watering greenhouses! They’re made of euro pallets and hard plastic. It collects rainwater and makes greenhouse gardening easier and more convenient. Using more than one miniature hothouse also gives you the freedom to switch up the temperature, light intensity, and humidity of each greenhouse by playing with different set-ups, helping you grow a more diverse garden.

10. Mason Jar Windows

Mason Jar Windows
Image Credit: dklafe via Instructables

For a funky glasshouse, this has an unusual look you might like. Similar to ordinary greenhouses, this is built with a hardwood frame and generous window space. However, instead of using glass or plastic panels, these have mason jar windows. It’s an attention-grabbing statement that’s both unique and great for the environment. Although it may take time, consider this fun project an opportunity to team up with family, friends, and neighbors to collect old glass jars for your one-of-a-kind modular greenhouse.

11. Sloped Roof Windows

Sloped Roof Windows
Image Credit: Kirklewellen via Instructables

Reclaimed windows are one of the best things to have when building a cheap greenhouse from scratch. Unfortunately, not everyone has enough windows for the classic glasshouse. If this is your situation, check if your windows are enough for a sloped roof. This roof design gives your greenhouse a sophisticated appeal and lets in tons of sunlight. With this, you’re free to source reclaimed materials for the rest of the structure.

12. Walled Greenhouse

Walled Greenhouse
Image Credit: RoeyLeon via Instructables

Perhaps you don’t have tons of space to spare. In that case, this wall greenhouse plan might be just what you need. It’s a tall and narrow structure installed against your house facade. While it takes up minimal square feet of your valuable yard space, it maximizes your vertical space for delicate plants. Since it’s small, just prepare a sturdy aluminum or wood shelf frame and a durable plexiglass enclosure.

13. Charming Scavenged Wood

Charming Scavenged Wood
Image Credit: rosemarybeetle via Instructables

This rustic greenhouse is made from salvaged wood and old windows and doors. It has an old-timey feel because this is mostly made from antique home furnishings and recycled materials found online and in flea markets. As much as possible, buy your greenhouse parts in pairs to create a balanced look in your greenhouse and make it look more expertly done. To tie it all in together, give it an elegant paint finish to enhance its lovely character before housing your favorite plants.

14. Gothic Arch

Gothic Arched greenhouse
Image Credit: ThomasJ1 via Instructables

This tent-like greenhouse is built in a gothic arch shape that’s easy to build yet amazingly sturdy. Although it’s large, you can build this on a tight budget using only a large plastic sheeting, repurposed timber, and PVC pipes. To make it winter hardy, stick to thicker and stronger wood to handle the weight of snow. It’s a great cold shelter for protecting your favorite plants from frosty weather!

15. Sprinkler Greenhouse Tunnel

Gothic Arch Sprinkler Greenhouse Tunnel
Image Credit: Ro James via Instructables

This large tunnel structure is a shaded low-cost greenhouse with a built-in sprinkler system. This plant-saving design is ideal for avoiding any overheated plants, especially for gardens in a sunny, warm environment. To build this shaded barn-style greenhouse, simply use polymer pipe arches, tinted plastic liner sheets, and jet spray bits. It can be a bit more complicated to build due to its irrigation system but the effort is well worth it in the end!

16. Mix Matched Window Frames

Mix Matched Window Frames
Image Credit: jddelta via Instructables

This adorable glasshouse gets most of its charm from its blend of mismatched windows that look like glass walls. Rather than going for similar-looking glass frames, this focuses on collecting as many inexpensive old windows as you can and making a beautifully chaotic glasshouse design. The differences in sizes and window panels draw the eye to the structure and make it look cozy and full of personality.

17. Recycled Yet Refined

Recycled Yet Refined
Image Credit: BobS via Instructables

This rustic greenhouse looks like a custom-built yard feature made with recycled wood and glass. This is built entirely from second-hand materials that were carefully gathered and joined together to create a scenic flower garden enclosure. Even if it’s made with reused materials, if you carefully choose quality items and build it attentively, this can last you a lifetime!

18. Thrifty Greenhouse

Thrifty Greenhouse
Image Credit: Organikmechanic via Instructables

Believe it or not, this lovely homemade greenhouse only cost $5! It stands with a recuperated wood frame, a polythene sheet cover, and wired fencing support. The cost to build this instant greenhouse will vary from person to person but as long as you work hard to find good quality wood pallets and frames, you’ll be good to go. For a better explanation of how this was made, this video with detailed instructions can help.

In Summary

The trick to super cheap DIY greenhouses is to take advantage of old and unused yet still high-quality building materials. By putting in a little more work to source the perfect reused wood planks, windows, and panels, the price of building your awesome greenhouse is quickly slashed.

Don’t be afraid to do what it takes to get your dream greenhouse— whether it means reaching out to local businesses for discounted excess items or mixing up different greenhouse concepts, these risks will undoubtedly pay off.

Which greenhouse idea caught your eye the most? Comment it down below!