If you’re looking for ways to extend your growing season, a cold frame greenhouse may be the thing.

We’ve pulled together a few ideas of different types of easy to build cold frames. These include step by step instructions for building a cold frame greenhouse using old windows plus a how-to video for building a complete cold frame on wheels, perfect for patios.

Types of Cold Frame Greenhouses

Window A-Frame – Quick, Cheap & Easy

If you have old windows in storage, you can put them to use to build a quick and easy A-Frame cold frame greenhouse. You just connect the two windows together with a pair of hinges to form an A-Frame.^[1]https://ohioline.osu.edu/hyg-fact/1000/1013.html

• Use wooden posts to hold the center of the A-frame in place.
• Place bales of hay around the open sides of the frame to help keep out the cold.
• Choose hardier plants able to handle cold weather.

Trunk or Box Frame

If you have an old wooden trunk, you can turn it into a nifty cold frame in just a few minutes. Or, you can build a rectangular box.^[2]https://www.motherearthnews.com/organic-gardening/garden-with-cold-frames-zmaz07djzgoe.aspx

1. Remove the hinges from the lid, and take the lid off the trunk.
2. Use a saws-all to cut the bottom out of the trunk, and do the same for the top of the lid.
3. Dig a hold about 1 foot into the soil.
4. Add a 6″ layer of gravel.
5. Place the trunk into the hole, and fill it with 6 inches of soil.
6. Use clear plastic sheeting as the transparent lid of the trunk
7. Re-connect the hinges to make your cold frame complete.

PVC Frame

If you don’t want to spend a fortune, you can make a cheap hoop house greenhouse using PVC piping.^[3]https://doorgarden.com/10/50-dollar-hoop-house-gree%E2%80%8Bn-house

• Use PVC pipe lengths, corner joints, and PVC glue to make a simple rectangular frame.
• Bury the bottom 6 inches in soil.
• Use clear plastic as the walls and the lid.
• Staple a wooden board to one end of the plastic used as the lid. The weight of the board will ensure that the plastic stays in place, but you can easily open your clear frame when you want to access the plants.

Make Your Own Cold Frames

Old windows, shower doors and glass doors are perfect for DIY Cold Frames. You can check with window replacement companies for a free source of old windows that would be perfect for creating an entire garden of cold frames.

In fact, a great project to do inexpensively is to find a free source for these old windows, then build raised beds for a raised bed garden with cold frames!

But, if you can’t find—or don’t want to use—old windows, the materials list in this project includes acrylic glazing, and the pdf linked at the end provides everything you need to know to make it.

MAKE A WINDOW COLD FRAME GREENHOUSE:
For a free source of old windows, contact window replacement companies in your area.
~GardensAll.com

Building a Cold Frame from Scratch

To get you started in building your own, below is a materials list. We’ve included links, should you prefer to have things delivered to your door.

Another option to save you time, is you can call or fax your list into most Lowe’s or Home Depot stores ahead of time and they can pull your items for you, so all you have to do is drive by on your way home to pick up and pay.

Just call your local home improvement store to confirm this is an option for you.

DIY TIP: You can send your materials list to your home improvement store. Most will be glad to pull the products for you to save time.
~GardensAll.com

Materials List

• Lumber/Plywood (use treated CCA) Hardware32 x 44 in. (2)
  • Front 2 x 6 x 61 in.
  • Back 2 x 6 x 61 in. (4)
  • Sides ½ in. x 2 ft. x 4 ft.
• (2) Acrylic glazing, 32 x 44 in. (2)
•  #6 x ¾ in. roundhead (Rh) screws*
•  #8 x 1½ in. flathead (Fh) screws*
• Plywood cut to shape T-hinges, 5 in. with screws (4)
• 2 x 2 x cut to fit (4) Corner braces, 3 in. with screws (8)
• Lids 2 x 2 x 39¼ in. (4) L-hooks (2)
• 2 x 2 x 28 in. (4) Perforated strap (2)
• Bricks (32)
• Paint

* Indicates zinc-coated

For the full instructions and materials list, you can download this PDF from Sac Gardens.^[4]https://www.sacgardens.org/articlesGarden/building_coldframes.pdf

Next, are step by step instructions for building a cold frame using old windows, followed by a how-to video for building a complete cold frame on wheels!
If you need to haul materials, here’s our favorite easy, effective and inexpensive pickup truck bed tie down system.

Build a Cold Frame Greenhouse Using Old Windows

by Jeff-o on Instructables.com

A cold frame! Basically a greenhouse with an open bottom, it can protect your plants from the elements and from animals. Because it acts like a greenhouse, you can start plants earlier in the year and keep them growing later into the year than normal.It’s easy to build one in a weekend using common tools and materials.

You’ll only need basic tools to build a cold frame. Since the cold frame will be pretty large, it’s best to build it outside or in a garage, or you may not get it out the door…TOOLS

• Hand-held drill (cordless or corded)
• Miter saw (powered is better, but you could do it with a hand saw and miter box)
• Jig saw, circular saw or table saw (anything that can cut large sheets of plywood)
• Screwdriver
• Tape Measure
• Carpenters pencil or other marker
• Paint brush

MATERIALS

• Two, Three or Four windows, with at least one dimension in common
• 2x2s (as required)
• 2x3s (as required)
• 2x4s (as required)
• Inexpensive 1/8″ or 1/4″ plywood
• Exterior wood screws (deck screws)
• Exterior wood-sealing paint
• Galvanized or brass hinges (may not be necessary if the hinges on the windows are still good)
• Big, sturdy exterior-grade handles
• Tube of latex sealant
• Common heating vent (optional)

I was fortunate enough to have a lot of the materials just lying around already. Some were left behind by the previous owners of the house, other pieces were left from tearing apart my basement. Use reused materials where you can!

For step by step instructions go to the source of this project and photo.^[5]https://www.instructables.com/id/Build-a-Cold-Frame-Using-Old-Windows/^[6]https://www.instructables.com/member/jeff-o/

Alternatives to Building a Cold Fram

We love our cattle panel greenhouse. They’re relatively easy and inexpensive to construct, and you can be up and running within a day.

We also use frost covers over our raised beds, indoor LED grow lights, and also an indoor greenhouse, though we’re primarily using that for growing microgreens and also starting seeds.

Making A Cold Frame on Wheels

This is a great video by Frank Howarth.

We hope you find this article helpful. Please let us know what you’re working on, and if you make a cold frame, please post your pictures on the GardensAll Facebook Page or drop us an email.