What is a root cellar?
A root cellar is simply a cold place to store vegetables and fruit for the winter months. It’s a way to store crops without using energy. A root cellar can be a traditional underground structure built into the side of a hill or an insulated basement room vented to the outside. It can be a large community root cellar or a small insulated box buried in the backyard. There are many different possibilities.
Building a root cellar
If you are planning to build a root cellar, we recommend checking out other root cellars in your area to get a sense of the size and type that would suit your needs. Additionally, Root Cellaring: Nature Cold Storage of Fruit and Vegetables by Mike and Nancy Bubel is a terrific resource if you’re thinking about building a root cellar. It covers all sorts of different types, from the simple to the extravagant! This book has been highly recommended by many people.
When creating and using your root cellar, keep in mind what root vegetables want which is to be in the ground – in a cool, dark, moist place. How can you create that situation?
Humidity is key to a successful root cellar. The ideal humidity level about 95%. Consider buying a hygrometer to measure the humidity. If you have a concrete floor, you may have to work to increase the humidity. Some ways of achieving this include keeping buckets or flat containers of water in the cellar, or by hanging wet blankets or bed sheets in the root cellar. If you have gravel flooring, you may want/need to pour water on the gravel cellar floor.
Ventilation is also important to a successful root cellar. Proper air circulation helps prevent mold growth, and also moves ethylene gas out of the root cellar. Ethylene gas is given off by fruit and vegetables as they ripen and can cause other vegetables to sprout.
You should ensure that your vents are rodent proof. Use 1/4" wire mesh to keep the critters out.
The optimal temperature for a root cellar is 1-5 degrees Celsius. Building your root cellar below ground – ideally below the frost line – will help greatly in keeping it cool. Thermal mass, in the form of the structure, the concrete and/or gravel and the food itself, help the root cellar to retain the cold.
One of our root cellar tour hosts keeps a jar of water in her root cellar to monitor the temperature. When the water freezes, it’s time to close the vent.
Storage Vegetables and Fruit
Onions, garlic, pumpkin and squash do not belong in a root cellar but they can be kept well into the winter months. They should be stored somewhere cool and dry.
Keep carrots, beets and parsnips in sawdust, straw, sand, or dry leaves. Sand, with some water added, is great at keeping moisture in – BUT is it very heavy. Dry leaves are easy to come by and free.
Potatoes and apples can be left loose in bins. Many people suggest keeping apples and potatoes separately, as the ethylene gas given off by apples can cause potatoes to sprout. However, all three of our root cellar tour hosts keep their apples and potatoes in the same cellar and none have experienced problems.
A great way to store your apples is to have a barrel or box in your root cellar with apples layered – varieties that keep best should be placed at the bottom and the varieties that are quicker to spoil should be at or near the top. This will give you variety as you eat through your barrel of apples!
There is a variety of tomatoes that keeps well, ripening late. This variety is simply called “keeper tomatoes”. They, like all tomatoes, should NOT be stored in a root cellar. They can be stored on the vine (pulling out the whole plant at the end of the season) or they can lay as loose tomatoes on top of dry leaves as they ripen.
It’s important to monitor the veggies in your root cellar, removing any that have mold so that it doesn’t spread.
How much should you store?
Every family has different tastes and needs, so it’ll take some trial and error to figure out the amounts that work for you. One of our root cellar tour hosts shared her list with us. They store the following for their family of five:
100 lbs potatoes
75 lbs carrots (could go as high as 100 lbs)
30 lbs beets
20 lbs turnips
7 chinese cabbages
10 lbs parsnips
100 lbs of apples
30-60 lbs pears (depending on the crop in their backyard).
100 lbs onions (but not in the root cellar)
Experiment! Unheated porches, basements, attics, garages all have potential to be mini-root cellars.
Bubel, Mike and Nancy (1991). Root Cellaring: Nature Cold Storage of Fruit and Vegetables. Second Edition. Storey Publishing.
Cornell Cooperative Extension. Storage Guidelines for Fruit and Vegetables. http://www.gardening.cornell.edu/factsheets/vegetables/storage.pdf
Complete with a table showing produce names, temperatures, relative humidity and length of storage.
Kerr, Bonnie. The Green Life Farm’s Blog: http://thegreenlifefarm.wordpress.com/
Maine Organic Farmers and Growers Association. (2008). “Root Cellars: Safe and Secure from the Corporate Food Chain” http://www.mofga.org/Publications/MaineOrganicFarmerGardener/Fall2008/RootCellars/tabid/984/Default.aspx
Maxwell, Steve. (2004). “Build a Basement root cellar”. Mother Earth News.
Organic Gardening. “Building A Root Cellar”. http://www.organicgardening.com/feature/0,7518,s-5-19-173,00.html
Ries, Victoria (2001). “A Root Cellar for your Homestead”
Tortorello, Michael (2008). Food Storage As Grandmas Knew It. New York Times. November 5, 2008. http://www.nytimes.com/2008/11/06/garden/06root.html?_r=1