How Do I Build A Root Cellar For Storage?

“I’ve been getting heavily into backyard farming and have really loved the process so far. Lately, I’ve been thinking about how nice it would be to have a root cellar to store all the produce I’m harvesting, but I’m not exactly sure where to begin or how to build one. I live in the countryside, so I have plenty of space, but I’m concerned about things like temperature control, moisture, and making sure everything is stored safely. Can you walk me through the process of building a root cellar and any important considerations I should keep in mind?” thanks, Robert, Gloucestershire, UK.

It’s fantastic to hear that you’re diving deeper into backyard farming, Robert! Building a root cellar can be an excellent decision, especially when you’re producing more food than can be immediately consumed. Root cellars have been used for centuries to store fruits, vegetables, and other foods through cold months, using natural cooling, humidity, and insulation from the earth to keep produce fresh. Let’s dig into how you can build your own, the different factors you’ll need to consider, and some tips to make sure it’s as effective as possible.

1. Understanding the Purpose of a Root Cellar

At its core, a root cellar is a storage space used to preserve food through natural means. It allows you to take advantage of the earth’s consistent temperature below ground, which typically stays cooler and more stable than above-ground environments. The goal is to slow down the aging process of stored items while keeping them safe from pests, rot, and extreme temperature fluctuations.

However, the effectivity of a root cellar hinges on various factors such as temperature, humidity, ventilation, and the type of produce you plan to store. Each of these aspects plays a significant role in maintaining the desired environment within the cellar.

2. Choosing the Right Location

The location of your root cellar is crucial for its functionality. Here’s what to consider:

• Elevation: The lower you go, the cooler it tends to be. However, you don’t want your root cellar to become a sump for rainwater, so avoid placing it in a low-lying area where water might pool. A slope can be ideal as it helps with drainage and easier access.
• Sunlight Access: If possible, locate your root cellar on the north side of a hill or slope, where it’s less exposed to direct sunlight, maintaining a cooler internal temperature.
• Proximity to Your Home: Think about convenience. Ideally, the root cellar should be close enough to your home to make access easy, particularly during cold months, without being too close to interfere with your home’s structure or damp conditions.
• Soil Type: Sandy and silty soils are generally more stable and provide better drainage than clay soils, which tend to hold water and can create damp conditions that may impact storage.

3. Key Components of a Root Cellar

Let’s break down the main components that come together to make a functional root cellar:

3.1 Insulating Earth Surroundings

One of the key benefits of a root cellar is that it’s often built underground or partially underground. The soil acts as natural insulation, which is critical for maintaining a consistent cool temperature. While enhancing the insulation process, remember:

• Depth of the Build: A significant portion of the structure should be below the frost line to ensure the internal temperature remains constant throughout the year.
• Wall Insulation: Use natural insulation materials like straw bales or earthbags along the inside walls to further stabilize the temperature.

3.2 Ventilation System

Good ventilation is essential for controlling humidity and preventing the buildup of spoilage-promoting conditions like excess moisture and ethylene gas. Here’s how you can achieve it:

• Air Inlet and Outlet Pipes: Typically, root cellars have two vents—a lower one for drawing in cooler air and an upper one for expelling warmer air. Position the intake pipe near the ground and the exit pipe near the ceiling.
• Air Exchange Rate: Ensure that air movement is regular but not too rapid, as this could lead to uneven temperature distribution.
• Adjustable Vents: Consider installing adjustable vents that you can open or close based on the season and the level of humidity or temperature inside the root cellar.

3.3 Moisture Control

The right humidity level is vital for keeping produce fresh. Most root vegetables benefit from high humidity, which prevents them from shriveling and drying out:

• Flooring: A dirt or gravel floor is typically best for maintaining appropriate humidity levels, as these materials naturally hold some moisture.
• Shelving and Storage: Use wooden shelving, which can absorb and release moisture, helping to moderate the internal environment. You might also want bins for different vegetables, particularly those that prefer different humidity levels.
• Water Buckets: In dry conditions, you can place shallow pans or buckets of water inside to introduce moisture into the air.

3.4 Pest Prevention

Your carefully stored produce can end up ravaged by pests if you don’t take steps to protect it. Common root cellar pests include rodents, insects, and fungi:

• Sealing the Structure: Preventing entry is your first line of defense. Seal any cracks, holes, or gaps in the walls, ceiling, and doors.
• Rodent Barriers: Consider installing metal mesh or hardware cloth underneath the structure and around the vents to keep rodents from burrowing in.
• Fungus and Mold: Ensure proper drainage around the root cellar and maintain good ventilation to keep moisture levels in check, minimizing the risk of mold growth.

4. Building Methods: Types of Root Cellars

There are various styles of root cellars, each with its strengths and suited environments. Let’s explore some of the most common types:

4.1 The Classic Underground Root Cellar

This type of root cellar is completely or mostly underground and is the most common design for serious storage needs:

• Construction: Digging a large pit, lining the walls with concrete or brick, adding a concrete slab roof, and covering the structure with earth for insulation.
• Cost and Labor: This is the most labor-intensive and costly to build but offers the best long-term storage.
• Pros: Superior temperature consistency, large storage capacity, built-in insulation from surrounding earth.
• Cons: Requires significant digging, construction expertise, and investment.

4.2 Bermed or Mounded Root Cellar

This type involves constructing a cellar on the ground surface, but then building up earth around it to insulate it:

• Construction: Build a small structure out of wood, stone, or earthbags; pile earth over and around it, leaving one side for entrance.
• Cost and Labor: Quicker and less expensive than digging a full underground cellar, especially on a property where excavation is difficult.
• Pros: Easier to build, better drainage, can be built on less stable soil.
• Cons: Less natural insulation means greater temperature variance.

4.3 Basement Root Cellar

If your home has a basement, converting part of it into a root cellar might be a simpler option:

• Construction: Section off a part of your basement, insulate the walls, and add ventilation to match proper cellar conditions.
• Cost and Labor: Less costly than a full underground cellar. Requires smaller modifications—ideal for suburban homes.
• Pros: Accessible from inside your home, less risk of flooding, lower construction cost.
• Cons: Less temperature regulation compared to underground cellars, careful planning needed to avoid moisture issues.

5. Setting Up Your Root Cellar Interior

Now that you’ve decided on a type and built your root cellar, it’s time to set it up for optimal storage:

• Shelving and Storage: Install shelves along the walls for easy access to stored items. Wooden crates or old drawers can also be repurposed as storage bins.
• Temperature and Humidity Monitoring: Place a thermometer and hygrometer (a device that measures humidity) inside the cellar to keep track of conditions, allowing you to make adjustments as needed.
• Partitioning: Consider using partitions or different sections for produce that requires varying conditions. For example, apples and potatoes shouldn’t be stored near each other, as apples produce ethylene gas, which speeds up the ripening (and spoiling) of potatoes.
• Lighting: Keep lighting simple and use it sparingly. Some produce can degrade quickly when exposed to light, so only use illumination when accessing produce.

6. Maintenance and Troubleshooting

Even the best-built root cellars require ongoing attention. Here’s how to maintain and troubleshoot common issues:

6.1 Temperature Fluctuations

Monitor the internal temperature. If it varies too much, check for issues like gaps in the structure, poor ventilation, or failing insulation. Consider adding or adjusting vents, sealing gaps, or adding more insulation where needed.

6.2 Humidity Control

If the air inside feels too dry, try adding more water pans or increasing the soil surface area that’s exposed. If the humidity is too high, improve ventilation, remove excess water sources, or consider a dehumidifier.

6.3 Pest Invasions

Regularly inspect your produce and storage area for signs of pests. If an invasion occurs, set traps, use natural repellents like mint or cedar, or consider laying down diatomaceous earth, which can deter crawling insects.

6.4 Mold and Mildew

Fungal growth can usually be traced to poor ventilation or excess moisture. Improve air circulation, and consider using a mild vinegar solution to clean affected surfaces. Make sure the source of excess moisture is identified and mitigated to prevent recurrence.

Final Thoughts…

Robert, building a root cellar can be a rewarding project that significantly extends the usability of your homegrown produce. The key is taking the time to plan it out, considering factors like location, temperature, humidity, and pest control to ensure your storage space functions efficiently. Thanks for reaching out—happy building!