Building a Cold Frame: A Beginner’s Guide

As winter approaches, many gardeners are looking for ways to extend the growing season and protect their plants from the cold. One effective and affordable way to achieve this is by building a cold frame. A cold frame is a simple and versatile structure that acts as a mini greenhouse, providing a warm and sheltered environment for plants to thrive even in colder weather. In this blog post, we’ll walk you through the steps to build your own cold frame.

Materials Needed

Before starting the construction of your cold frame, gather the following materials:

• Four wooden boards or concrete blocks for the base
• Additional wooden boards for the frame
• Hinges
• Clear plastic or glass panels for the lid
• Screws or nails
• Latches or hooks to secure the lid
• Hammer or screwdriver
• Saw

Steps to Build a Cold Frame

Step 1: Choose a Location

Select a location for your cold frame that receives ample sunlight, preferably facing south to maximize exposure to the sun.

Step 2: Build the Base

If using wooden boards, arrange them in a square or rectangular shape to form the base of the cold frame. If using concrete blocks, stack them to create the base. Ensure that the base is sturdy and level.

Step 3: Construct the Frame

Using the additional wooden boards, construct a frame on top of the base. The height of the frame should accommodate the height of the plants you intend to grow inside the cold frame. If building a frame is an issue, I have dug a hole in the ground just a little smaller than the old wooden window that I used for the lid and then used the dirt I removed to construct a crude frame and seal the edges.

Step 4: Install the Lid

Attach the clear plastic or glass panels to the frame using hinges, allowing for easy access to the plants inside. Make sure the lid can be propped open for ventilation on warmer days. An old window will work as well.

Step 5: Secure the Lid

Install latches or hooks to secure the lid in place, especially during windy conditions.

Step 6: Prepare the Soil and Plant

Fill the cold frame with nutrient-rich soil and plant your desired vegetables, herbs, or flowers. You can also put seed starter trays or pots in it as well.

Tips for Maintaining Your Cold Frame

• Monitor the temperature inside the cold frame regularly, especially on sunny days, to prevent overheating.
• Open the lid on warm days to allow for ventilation and prevent the buildup of excessive heat and humidity.
• Close the lid in the evening to retain heat and protect plants from cold nights.
• Insulate the cold frame with additional layers of clear plastic or bubble wrap during extremely cold weather.

By following these simple steps, you can build a functional cold frame to continue gardening well into the winter months, or have a way to start plants in early spring. Not only will this extend your growing season, but it will also protect your plants from frost and harsh weather conditions.

Happy gardening!