Cold Frame Gardening – Uses for a Cold Frame

Cold frames are a great tool to extend the garden season. Here’s a look at the history and uses of cold frames.

Cold Frame Gardening – Why I love cold frames

By Zac Mace

For something that is so simple and relatively inexpensive, a cold frame can make a huge difference to the length of your growing season.

Background

Historically cold frames were located on the exterior of a heated green house and comprised a glazed frame with hinged glass roof called a light. These frames were unheated, hence the term “cold” frame. The idea was that seedlings initially grown in the greenhouse would be moved to the cold frames to harden them off. To harden off a seedling, it is placed within the cold frame and over a period of weeks the roof light is opened more and more, gradually acclimatising the seedlings to the outside conditions. This process helps prevent any shock when the seedlings are planted out which can cause a check in growth. This is particularly important with cauliflowers where a check in growth can result in the heads never forming properly.

Modern cold frames have eschewed glass in favour of modern materials, generally polycarbonate. Modern polycarbonates are as clear as glass and in the double glazed variety fitted to most cold frames it provides thermal insulation as good as glass also. Polycarbonate does not shatter, or break harmfully and is therefore a perfect material for use in gardens where there are pets or children.

Generally cold frames are designed either glazed down to the ground or with a solid wooden frame. There are pros and cons to both designs, although for the British climate the solid wooden sides are considered to have and advantage as they absorb warmth throughout day and slowly release it during the night, leading to higher average temperature at night. However on an overcast day the fully glazed cold frames can capture more sunlight and therefore more heat.

Uses

Cold frames are incredibly useful for hardening off seedlings, which can be a real chore without one. However they can also be used like a mini greenhouse to germinate plants earlier than they would otherwise grow outside. With just a cold frame it is possible to have home grown cauliflower ready as early as late May. Simply sow your cauliflower seed in your cold frame at the end of October and the seedlings should be ready to plant out at the end of February or early March, easily gaining a month or more of growing time.

In fact during the course of a year, all of the following usually end up in the cold frame at some point:

• Cauliflower
• Onions (from seed)
• Courgettes
• Sweet corn
• Lettuce

A cold frame is one of those things that you don’t think you need until you have one and then you wonder how you ever managed without. Mine is full pretty much throughout the growing season and was certainly money well spent. In fact just the effort saved when hardening off seedlings would be sufficient to make it great value for money.

I have become a true cold frame convert and really couldn’t face gardening without one anymore.

Author Zac Mace Resource: Zac Mace is a keen vegetable gardener in his spare time when he is not working, entertaining his two daughters or updating his website dedicated to Cold Frames. Zac is happy to answer gardening related questions, you can get in touch with him through his website.

More information about hardening off using a cold frame is available on Zac’s website.

Article Source: Cold Frame Gardening – Why I love cold frames
Article From: Organic Gardening Articles