9 DIY Cold Frame Ideas To Keep You Growing - Backyard Boss
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9 DIY Cold Frame Ideas To Keep You Growing

A cold frame is a handy gardening accessory that’s also an alternative to a greenhouse. Mainly, these frames are boxes that lie flat on the ground with a glazed, sloping, and transparent lid. They are convenient if you have limited space or are looking for a cost-effective alternative to a greenhouse.

Below you’ll see some cold frame designs you can DIY with items you probably have lying around at home. Give your old things a second chance so they can help your plants grow; come rain or shine!

9 DIY Cold Frame Ideas To Keep You Growing

Like a greenhouse, cold frames allow you to grow herbs, fruits, vegetables, and flowers all year round, regardless of the climatic conditions. In addition, you can use cold frames for overwintering your perennials that would otherwise not survive harsh weather.

Here are some easy-to-DIY cold frame ideas to help you build a cozy home for your plants to stay in during harsh weather.

1. Shower Door Cold Frame

If you feel like you need a new shower door but don’t know what you would do with your current one, repurposing it as a cold frame cover is the way to go! Transparent shower doors can be an effective covering for a cold frame.

Since shower doors are see-through, they provide easy view and access to your plants as they embrace the greenhouse effect. As part of this design, you will need to consider the weight of the shower door on the rest of your cold frame and the fog that could collect on it that could potentially erode the shower door.

2. Cold Frame Tent 

This cold frame tent is simple to DIY, needing only basic tools and screws. If you do it properly, it can last throughout the seasons. Cold frame tents, made of plywood and poly sheeting, allows rain drainage and fallen leaves to glide off the sides, all while keeping the plants snug and protected from harsh elements. A possible swap-in for plywood is oriented strand board (OSB). OSB is essentially wood chips stuck together, whereas plywood is a combination of thin veneer sheets stuck together with a hot press. Both plywood and OSB share the same exposure durability. However, plywood is more stable due to its structure and less likely to shrink, swell, cup or warp.

3. Old Window Cold Frame

Salvage old windows for this awesome cold frame design. This cold frame design works well when growing larger plants in your raised garden beds.

Consider the number and weight of the windows you’d want to use and whether the base of your cold frame will be able to support them. The type of window you choose can also affect accessibility and light transmission to plants. You’ll need to decide between fixed, casement, and double-hung windows for your cold frame.

4. Repurposed Door Frame

Like the old window design, you can repurpose an old door for a cold frame. That being so, there’s much to consider about the type of door you choose.

The ideal door should have plenty of windows to allow light to pass through. It should also be lightweight so as not to compromise the cold frame structure. A lightweight door will make opening and closing for air circulation much easier and less laborious.

Because doors are quite sizable, this design is best for a tall cold frame. Alternatively, you could utilize a double door and make an A-shaped cold frame to shelter your plants.

5. Plexiglass Cold Frame

Plexiglass is an all-rounding material that boasts chemical and impact resistance, innate weather ability and UV resistance, and optical clarity. This sleek plexiglass-topped cold frame allows your plants to manage the snow, rain, and sweltering sun easily.

While plexiglass is on the pricier end, you can pair it with a durable wood like lumber or cedar for a cold frame worth the investment.

6. PVC Cold Frame

These cold frames, consisting of a PVC frame and plastic sheeting, are easy to set up, portable, and efficient at retaining heat. PVC is chemical resistant, fire retardant, lightweight and sturdy. You can build a cold frame or a hoop house to suit your garden with the correct number of pipes and connectors.

Since plastic sheeting is lightweight and transparent, you can drape it over the PVC frame and secure it with zip ties. Plastic sheeting used for greenhouses can last up to four years before needing replacement.

7. Plastic Bottle Cold Frame

Give a new purpose to plastic bottles by using them to make a cold frame. This cost-effective and environmentally-conscious design will require as many plastic bottles as possible and wooden planks or PVC pipes for the general structure.
There are many ways to go about using the bottles. For example, you could either make holes and slide them through a wooden stake to create walls for the cold frame or cut the bottles lengthwise and flatten them to connect them into one plastic cover. Either way, your plants will receive ample warmth and light due to the greenhouse conditions the plastic bottles create.  

8. Brick and Window Frame

This brick cold frame, topped with a repurposed window, is a permanent option that can blend in with the rest of your house. Unlike the previous designs, this cold frame won’t stand out, especially if you use similar bricks or tiles to the ones on your house or patio.

In addition, the brick structure will hide your plants in plain sight from potential pests and rodents. As an added benefit, you won’t have to worry about the weight of the window as it sits atop the brick foundation.

9. Straw Bale Cold Frame 

Perhaps the most unconventional cold frame would be this straw bale design. This cold frame is a temporary structure that can protect hardy vegetables in autumn and winter.

Straw bales are among the most economical forms of thermal insulation and have great insulation qualities with an insulation value of R28 or higher. For identical thickness, straw insulates similarly to fiberglass batts but costs much less. Once the bales are in place, you can top them with a transparent material like an old window or a piece of polycarbonate.

When springtime rolls around, you can dismantle the frames and use the straw for mulching, straw bale gardens, and composting.

Time to Fall it a Day

There are many creative ways to DIY the perfect cold frame for your plants. From using shower doors to windows and plastic bottles to straw bales, as long as your cold frame provides your plants with sufficient warmth, light, air, and protection from harsh weather, you’ve nailed it!

Leave your experiences, thoughts, and questions in the comment section, and as always, please share!

Happy Gardening!