By Andy Patterson, Tutor at ADL - Academy for Distance Learning
If you have tried growing your own fruit and vegetables, you will have noticed that it is unavoidable that a glut of produce arrives in the autumn time. In the days before electricity and powered transport, and facing the bleak winter, remote farming communities developed ways of locally storing the harvest’s abundance over winter. One such method which is becoming popular again amongst the ecologically- minded, is the traditional root cellar.
Image in Public Domain
Most root cellars poke out of the ground slightly and have a stairway leading to the underground portion. They vary in size considerably. Using the root cellar principle can be as simple as having an aluminium bin in the ground, sealed and covered with mulch. Or it can be a larder for a whole community.
Basements, garages, barns, or the northside of a hill or berm are ideal spots for root cellars. With creativity and experimentation, root cellars can provide a variety of environments allowing you to store all of your produce under one roof. Despite the rickety appearance and home spun charm of many traditional root cellars, they nearly all provided microclimates for the storage of a variety of crops for as long as possible. Basically, anything that grows underground, and some things that grow above ground too, can be stored underground, provided the conditions are right.
Construction & Using Root Cellars 
A root cellar is an attempt to create conditions similar to those which exist underground. This offers several advantages to prevent crop spoilage; it is dark, moist, and cool, but not freezing. The precise combination of environmental factors must be kept within well controlled limits in order to prevent microbial decay or pests. Crucial to this process is controlling temperature and humidity. Controlling only two variables may seem simple, but it does get confusing when you consider that different crops like different environments (see the table below).
From Maine Organic Farmer’s and Gardener’s Association
Image in Public Domain.
This method of storage is also suitable for market gardeners as well as homesteaders. Whole crops can be stored over winter underground or in chambers if required. Several contemporary root cellars are in production, which can be buried under the ground, which provide a sustainable method of food storage and refrigeration. They are often made of rodent and insect proof materials which will not rot from ingress of water, and which can be environmentally monitored and controlled to a greater degree than the traditional versions.
If you are interested in traditional small scale food cultivation, or larger scale agriculture, landscaping and construction, ADL has the courses to help you.
 The Joy of Keeping a Root Cellar: Canning, Freezing, Drying, Smoking, and Preserving Harvest Paperback. Jennifer Megyesi, Aug 2016.
 The Complete Root Cellar Book: Building Plans, Uses and 100 Recipes. Steve Maxwell and Jennifer Mackenzie, May 2010
 Root Cellaring: Natural Cold Storage of Fruits and Vegetables. Mike and Nancy Bubel, Sep 1991
 Fact Sheet #15: Storing Garden Vegetables. Maine Organic Farmer’s and Gardener’s Association. Eric Sideman, PhD and Cheryl Wixson, PE. August 2010.
 Construction & Using Root Cellars (PDF). Many Hands Organic Farm, Massachusetts. Jack Kittredge & Julie Rawson, Dec 2012.