Cold Frame Greenhouse

A cold frame greenhouse is an indispensable tool for any gardener who wants to extend their growing season. Consider it as a type of mini-greenhouse. A cold frame will work just about anywhere, in a backyard or on a small farm.
While it may seem intimidating at first, using a cold frame greenhouse doesn’t have to be a complicated task. With some basic knowledge of how to use this essential gardening tool, you can get the most out of your garden year-round. A cold frame greenhouse is also a great way to get started with a gardening/vegetable business.
Here are some step-by-step instructions on how to use a cold frame as well as a discussion of the different types of cold frames available to you. Soon you’ll be ready to extend your growing season and maximize the potential of your garden!
What is a Cold Frame Greenhouse?
A cold frame greenhouse is an essential gardening tool used to extend the growing season of plants. It is essentially a box made out of glass, wood, or plastic, with some type of insulation such as straw, hay, or newspaper inside. Even straw bales can be used as the sides as long as it has a cover over the interior area.
Often people will build a wooden cold frame and then cover it with a salvaged wooden window pane. This works well, but does require effort to build.
There are also kits that you can purchase and all come with assembly instructions.
The box should have a lid that can be opened and closed. The box is placed in an area that receives plenty of sunlight and can be opened and closed to control the temperature inside.
Temporary Cold Frame

Your cold frame does not have to be a permanent structure in your yard. The covered box or structure can be a temporary configuration that you remove when not using it. There are some plastic cold frames on the market that are very light-weight and work well for this purpose.
What are Cold Frames Used For?
Cold frames are great for starting plants or overwintering dormant plants. Since the cold frames keep plants warm, cold weather crops can be started in the very early spring which will allow you to get a harvest before the heat sets in.
What is the Best Location for a Cold Frame Greenhouse?
The box should be placed in an area that receives plenty of sunlight and can be opened and closed easily. When placing your cold frame, you should make sure it is facing south so that it can receive the most sunlight.
Avoid Exposure from Extreme Weather
Additionally, you should make sure the location is sheltered from strong winds and extreme weather conditions. Depending on your climate and the type of plants you are growing, you may need to place the cold frame in a spot that is more or less sheltered from the elements.
Place Cold Frames in an Open Area

Be sure to keep your cold frame away from trees, shrubs, buildings, and other structures that could block sunlight or impede air circulation.
Check Local Regulations
In some locations, you may want to double-check with local regulations to ensure that there are no restrictions on where you can place your cold frame.
Crops and Cold Frames
When it comes to selecting the best crops for your cold frame, there is no one-size-fits-all solution. Generally speaking, cool weather crops like kale, spinach, and lettuce are well suited for growing in a cold frame. You can also grow herbs.
To give your gardening season a head start, you can plant your warm weather seedlings in your cold frame. As the outside weather continues to get warmer, choose the best time to replant your seedlings in your garden.
Different types of crops have different requirements when it comes to temperature, so it is important to select plants that are well-suited to your climate. In general, most cool weather vegetables such as lettuces, kale, spinach, and chard are ideal for the cold frame.
Temperatures

You should aim to keep temperatures inside the cold frame around 50 – 68 degrees F during the daytime and 41 – 59 degrees F at night. To achieve these optimal temperatures, you may need to adjust the amount of sunlight your cold frame receives by either raising or lowering the lid, or by adding additional insulation.
If the cold frame is getting too hot during the day, even after lifting the lid, you can cover the box lightly with a sun-screen mesh to protect the plants from intense sunlight but still allowing air to circulate.
Care of Your Cold Frame Greenhouse
To ensure that you get the most out of your cold frame, it is important to take proper care of it. You should check the wooden, glass, or plastic panels periodically for damage and replace them if necessary.
Regularly, you should inspect the insulation material (straw, hay, or newspaper) each season to make sure it is still in good condition. Anything moldy or breaking down should be replaced.
Recap
A cold frame greenhouse is ideal to protect plants during the off-season cold temperatures. It is a hot bed that can be used to grow seedlings or protect overwintering dormant plants. A real advantage is that a cold frame does not take up a lot of space.
To prevent excessive heat buildup and protect your plants, you should vent the cold frame on hot days by opening the lid and/or side panels slightly. Lastly, to deter pests and diseases, you should clean the interior of the cold frame regularly and water your plants properly.
Different Types of Cold Frame Greenhouses
Here are a variety of different cold frame greenhouses which can meet almost any situation. All of them are rated 4 stars or above.
MCombo Wooden Garden Portable Greenhouse Cold Frame Raised Plants Bed Protection
The MCombo Wooden Garden Cold Frame is a traditional, on-the-ground structure with an opening lid. It is framed in wood with transparent polycarbonate glazing boards to allow light to enter or you to see into the box without opening it. It is a simple design that has proven to be effective over centuries of gardening.
Customers give it 4.7 for easy to assemble, 4.4 for sturdiness, and a 4.3 for maneuverability. Available in orange or grey. A good all-around favorite of gardeners!
$89.00 CLICK HERE for more information
MCombo Double Box Wooden Greenhouse Cold Frame Raised Plants Bed Protection (Double-Hinged Lids)
Again, MCombo has built a traditional cold frame, but this one has a nice twist. The MCombo Double Box Wooden Greenhouse Cold Frame Raised Plants Bed Protection has a double-hinged lid. This feature makes it very easy to ventilate the structure.
Roof grooves allow water to drain off of the roof and not collect. The transparent polycarbonate glazing boards allow you to see inside the box easily. It is a simple, elegant design that can be out in the yard or close by your patio.
Interestingly, it comes in a number of different colors: orange, gray, green, natural, and blue.
$119.99 CLICK HERE for more info!

Exaco Juwel Biostar Cold Frame Greenhouse
Need something a little larger? This cold frame is approximately 5 feet by 2.5 feet–you could even plant a small garden in here. This cold frame is insulated with 8mm double walled polycarbonate panels which allow it to retain heat better than glass. The double skin panes are weather-resistant as well as UV resistant and are guaranteed against yellowing for 10 years.
The Exaco Juwel Biostar Cold Frame Greenhouse has 3 roof windows and each opens independently. There is an additional really great feature that we have on our greenhouse window and love it! On one roof panel is an automatic window opener. It will raise and lower the panel as the temperature changes. The other 2 panels have adjustable height prop-up stanchions.
This cold frame is very easy to assemble and will dismantle in 5 minutes when you are not using it. Best of all, there is a 3-year warranty for manufacturer defects. Made in Austria, styled after Austrian-style cold-frame greenhouses.
$449.99 CLICK HERE for more info!