Top 3 Ways On How To Build A Cold Frame

Have you ever wondered how you can start seeding sooner, extend your growing season and harvest your crops longer? Well, with a cold frame this is possible.

Furthermore, with everything going on in the world, having your own food source is much more important now. In this article we will discuss everything about cold frames, from building one to what plants thrive in them.

What Is A Cold Frame?

A cold frame is a rectangular box built with a transparent roof that prevents heat escape. The cold frame lets in sunlight, trapping warm air inside and protecting plants from harsh outdoor weather.

What Are The Benefits Of Using A Cold Frame?

  1. You Can Start Seeding Earlier In The Spring or Fall

Regardless of what time of year, have your cold frame in place two weeks prior to seeding. Furthermore, if you are seeding in the early spring or late fall, make sure you plant cool season plants such as lettuce or spinach to handle the colder temperatures.

For warm season plants, wait until the outdoor temperatures have stabilized and you are two weeks from your last frost date to plant.

  1. Provides Dormancy Over Winter

A cold frame provides the perfect conditions for your plants to go dormant over the winter months and jump to life in early spring.

For the best results add fallen leaves as mulch for frost protections, cover your cold frame from sunlight to keep plants dormant, and water inside lightly a few times a week.

Cold frames are used to start seeding earlier in the spring, extend your growing season, or protect plants from harsh weather such as wind.

  1. Extends Your Growing Season

By using a cold frame you are able to extend your growing season by an extra two months. The main benefit comes with springtime growth. 

  1. Harvesting Throughout The Winter Months

You may not be able to grow everything during the winter months but you are able to harvest what you planted in late fall.

Keep in mind they will most likely be cool season crops such as leafy greens. A cold frame can hold them and you can eat from each plant from December – early February before new plants start growing.

  1. Cold Frames Move Your Garden One Zone To The South

For each layer you place over your garden, your zone will increase by one. You will be able to grow a wider variety of plants and extend your growing season because of each layer of cold frame.

  1. Are Cheaper To Build Then Greenhouses

Especially for beginners, building a cold frame is a great cheap alternative then spending hundreds on a greenhouse to find out gardening isn’t for you.

How Do You Build A Cold Frame?

What Crops Can You Grow In A Cold Frame?

  • Leeks
  • Arugula
  • Broccoli
  • Cabbage
  • Green Onions
  • Rotselleri
  • Carrots
  • Mustard
  • Radishes
  • Lettuce
  • Kale
  • Spinach
  • Normal Celery
  • Bell Pepper
  • Chard

What Is The Difference Between A Cold Frame And Greenhouse?

The main difference between a cold frame and a greenhouse is their size comparison. Greenhouses are much taller with more air to work as insulation in the cold winter months. 

A cold frame is normally built low to the ground and placed over your plants.

Where Is The Best Place To Put A Cold Frame?

Place your cold frame overtop of the plants you wish to protect and have the sloped transparent roof facing the south or south-east direction for the most sunlight.

Ideally having your north facing side of the cold frame up against a wall for a windbreak is best practice.

How Do You Ventilate Your Cold Frame?

The most common practice for ventilating a cold frame would be to prop your lid up with a stick. For an automated method, purchase a thermostatic vent that will automatically open when the cold frame heats up.

Extra Cold Frame Tips

Tip #1

Your cold frame should be at least 1 foot at the front

Tip #2

The back should have at least a 1 inch rise for every foot of frame. This will insure the proper angle for your glazing

Tip #3

Place the cold frame in the ground for better insulation or a more permanent structure

Tip #4

30 – 45 degree angle for the roof to allow the sun to come into the cold frame and bounce around which heats it up.

Tip #5

Cold frames should have a 1 inch rise for every ft of frame width to keep rooftop slope at a 30-45 degree angle.

Tip #6

Start venting your cold frame when the outside temperature is 40 F or higher for growing plants and 45 F or higher for new seeds 

Tip #7

Anything below 55 F seeds won’t germinate or will have a poor germination rate. Start it indoors then move them outdoors with acclamation.

Tip #8

If temperatures drop below 20 F at night then start using your cold frame immediately

Tip #9

Late fall, winter, and early spring use a cold frame. Late spring and summer remove your cold frame

Tip #10

Building your cold frame no more than 4 feet wide will allow you to sit on either side and be able to reach the full width with your arms

Final Thoughts

Having a food shortage is more likely due to disease and economic troubles around the world. Being prepared and self sufficient should be plant A. We have made this website to help guide everyone into a happier simpler life.

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