This time of year, as we head inside and our gardens are covered in snow, we look for ways to keep enjoying fresh food.
Whether for commercial sale, home consumption or community food security, the root cellar is an important infrastructure for growers, especially for those in northern climates.
Because root cellars are so important, I’m going to dedicate my next few articles to looking at them. First up, let’s explore how root cellars work by examining what you should store in them.
Roots in a Root Cellar
There are different types of root cellars and scales to suite all farms, homesteads and landscapes.
Some root cellars can be built into your home or barn, while others will be stand-alone structures or built into the side of a hill.
However, in all cases the word root cellar should be properly associated with storing primarily root vegetables—hence the word ‘root’ in the title. (You can see my previous article about other types of winter food storage, including ‘leaf cellars,’ pantries and more.) That doesn’t mean we cannot use a root cellar to store apples or onions.
But these items require different design considerations.
You can store apples in similar conditions to carrots. But apples and carrots cannot occupy the same cellar. Why? The ethylene gas apples emit during storage will make the carrots go bitter.
Onions, on the other hand, need drier conditions or they will mold.
So, again, the starting point for a root cellar journey is understanding how to store root vegetables. This requires high humidity, cold and no light. The following details conditions needed for the main types of cold storage for popular vegetables.
Apples, Beets & Carrots
- 32-40 F, 90-95 percent relative humidity (RH)
- Similar storage to fruits, but roots and fruits should not be stored together
Onions & Garlic
- 32-45 F, 50-60 percent RH
- Much drier, but too dry will cause desiccation
- 35-45 F, 90-95 percent RH
- slightly warmer conditions
By using a root cellar that stores “roots,” we are essentially in the business of maintaining the conditions roots need to remain dormant. That’s right—dormant!
Many of our favorite root cellar vegetables, such as carrots, beets, potatoes and winter radish, are actually alive. They’re simply resting in a natural state until the conditions for breaking dormancy return … or until they are eaten.
I like to approach understanding the conditions (temperature, humidity, light) necessary for proper root cellaring through the lens of dormancy for two reasons.
First, it reminds us about a few important aspects of root cellaring as a food preservation technique. Namely, we stay aware that vegetables like carrots in a root cellar are living foods. Unlike the salad available in winter at a grocery store, they have the vitality and nutrition of a plant that is still alive.
Secondly, as a living food that is a biannual (a plant that takes two seasons to produce seed), carrots can increase community food security. How? They provide a source of future seed saving and re-localization of variety selection for regional differences in climate and demand.
If you don’t eat all your carrots in the root cellar, you can just plant them in the garden. They will flower and produce carrot seeds!
There’s another reason I like to look at root cellar design by understanding dormancy, too. In many ways, we should give more attention to the critical importance of reducing fluctuations of storage conditions, which is a natural call to break dormancy.
Let’s understand carrots, beets and potatoes as “living entities.” In a cellar that mimics the natural conditions they might experience in a winter environment, they:
- adapt to grow
- build up a storage root
- convert starch to sugars with autumn cold weather
- go dormant over winter
- break dormancy in spring and grow anew.
With this perspective, we can see that, in a natural environment there are little calls to wake up as winter turns to spring. So little fluctuations in temperature, light and humidity should be avoided to improve root cellar vegetable storage.
Better to store your carrots at a few degrees warmer than ideal than have them fluctuate within a more ideal range on a daily or weekly basis. For that reason, good root cellar design should maximize the stability of cellar conditions .
Next up, we’ll explore some of the different design options for root cellars.