There was a time when almost every family had a root cellar of some kind. They all learned how to build a root cellar. However, with the advent of modern refrigeration, DIY root cellars have seemingly lost their value. Refrigerators in the house became a modern convenience, storing all foods between 32 to 40 degrees. But instead of long-term storage of valuable fruits and vegetables, we often find our crispers full of decaying produce that ends up going to the chickens, being composted, or worse yet, ending up in a landfill. It turns out that not all foods are best stored at temperatures as cold as modern refrigeration. Fruits and vegetables such as cucumbers, eggplant, snap beans, peppers, garlic, onions, pumpkins, squash, sweet potatoes, potatoes, tomatoes, tomatillos, and watermelon all prefer a warmer storage temperature closer to 50 degrees, and can actually be damaged by colder temperatures.
Luckily, nature has once again provided the perfect food storage option. With underground temperatures remaining constant at around 52 degrees F, and the presence of high humidity due to soil moisture, a root cellar dug into the ground is the perfect environment for the storage of not only fruits and vegetables, but also aging cheese, fermented vegetables, and jars of canned goods that we have run out of room for in the pantry. For those of us who farm or garden, keeping a root cellar underground or in the basement allows us to properly store the abundance we have been blessed with during the growing season.
Best Location for a Root Cellar
- Choose a location that is easily accessible. Root cellar conditions need to be monitored, and regular checks for signs of spoilage must be made. A neglected root cellar will be unsuccessful.
- Choose a north or northeast facing hill, mound, or corner of the basement. Soil can be warmed by the sun, so a north facing hillside or corner of the basement will provide the most steady cool temperatures. If you live in a region with extremely cold temperatures like Alaska, a south-facing option will prevent freezing in your storage space during the winter.
Ensuring Proper Root Cellar Conditions
- Provide ventilation for air circulation. Fruits and vegetables are constantly releasing off-gasses, some more than others. Some of these off-gasses can create spoilage or affect the taste of neighboring vegetables. Ventilation can be created by leaving space at the point of entry or through ventilation pipes. If you want to get really fancy (and efficient), a low intake air pipe can be installed to allow cool air in, and a high outtake pipe can be installed for the release of warm air and gasses.
- Food cellar humidity levels. Produce can quickly become dry and shriveled, or begin to break down without proper humidity. Many produce storage items do best in environments with humidity levels between 80-95%. In underground root cellars, these humidity levels are easily maintained in most climates. Basement root cellaring will often require added moisture to maintain these levels. Added moisture can be maintained through moist wood shavings or containers of water left to evaporate.
- Maintain the proper root cellar temperature. Fluctuations in temperature outside of the ideal range can cause fruits and vegetables to break down. A location that remains unaffected by outdoor conditions is ideal. In some regions, the months during which long-term storage is possible will be limited because of either extreme heat or extreme cold. Your point of access will be the weakest point in maintaining even temperatures, so be sure to face the opening to the north or northeast, unless you live in an extremely cold climate.
Different Types of Root Cellar Designs
1. The in-ground or underground root cellar
The traditional root cellar is dug into the side of a hill, or dug straight down into the ground, well below the freezing point of the soil for a particular region. Ideally the depth of the root cellar allows for standing room. This allows for easy management of goods and creates zones within the root cellar. Cold air sinks and warm air rises, so vegetables such as root vegetables that prefer colder temperatures can be placed closer to the ground.
2. Concrete Block Root Cellar
A dirt root cellar is an option, but leaves your storage space more open to critters who may think that you placed your abundance of produce there just for them. Instead, the root cellar can be lined with bricks, cinder blocks, or poured concrete slabs. Wood can also be used, but will eventually need to be replaced over time. Here at No. 9 Farms, since we live in “tornado alley,” we purchased a prefabricated concrete storm shelter and placed it underground. It works quite well for both purposes.
3. Above Ground Food Cellar
This is an area where you will have less control over temperature, and is more susceptible to critters who think you are sharing, but for milder regions, this can be an excellent option for short and long-term storage. Storing in crates of some kind is recommended for this option.
4. Food Storage in Your Basement
What could be more convenient than having your food storage in your house? On those cold winter days, walking out to the root cellar first thing in the morning isn’t always appealing. An underground basement can provide excellent storage conditions. Choose a north or northeast corner of the basement that is not connected to modern heating and cooling. This type of area can be created even in modern homes by closing off an area with walls and a door in a part of the basement where a vent is not present
How to Store Your Food in a Root Cellar
Check with your local extension office or online guides for specific lists of ideal root cellar temperatures and humidity levels for individual fruits and vegetables. A number of produce items will need to be cured before being placed into long-term food storage.
Onions and garlic should be cured in a warm, dry area in the shade for a week before being trimmed. After trimming, cure alliums for another two weeks. Temperatures in the 80’s and 90’s are preferable.
Potatoes should be cured in cool, dark, moist environment (such as your root cellar if you have room to spread them out) for a couple of weeks before being placed in a container with a lid. A loosely closed container will prevent shriveling.
Sweet potatoes can be tricky to cure because they are often harvested in the fall before freezing temperatures set in. Their ideal curing temperature is 85 degrees with high humidity. In most regions of the country, fall temperatures are well below this level. Here at No. 9 Farms we cure our sweet potatoes in the greenhouse for two weeks before moving them to the root cellar.
Pumpkins and winter squash can be cured at 70-80 degrees for a couple of weeks in a well-ventilated area. If there is concern of freezing nighttime temperatures, be sure to bring your squash indoors to prevent damage.
Cabbages and root vegetables prefer cool, moist conditions. Store cabbages with roots intact along with root vegetables in moist sand near the floor of the root cellar.
The environment of every root cellar will be different, just as the microclimate of every growing space if different. Over time you will get to know your space and the adjustments that need to be made. Listen to your fruits and vegetables—they will let you know if conditions are not ideal. Start small and learn the art of food storage. It will help you break the grocery store paradigm.
Stephanie Oaks lives in Ashland City, Tennessee, where she and her husband own and operate No. 9 Farms, an organic farm that specializes in berries, herbs, fruits and vegetables, and Christmas trees. Stephanie spends the remainder of her time homeschooling their two teenage children and teaching classes on organic gardening and healthy cooking.