How Do I Build A Root Cellar At Home?

“I’ve got extra space behind my garage, and I’d love to use it to build a root cellar. My only concern is the climate here—it gets pretty cold in Toronto during the winter, and I’m worried that a root cellar might freeze. Is there a way to prevent it from getting too cold inside? Also, if I’ve never built one before, what kind of design do you recommend starting with?” Thanks, Robert, Toronto, Canada.

How Do I Build A Root Cellar At Home?

Building a root cellar is a great idea, Robert! Especially since the winters in Toronto do get pretty frosty. A root cellar is one of the best ways to keep your homegrown veggies fresh during those long, chilly months. Whether you’re storing potatoes, carrots, apples, or cabbages, a good root cellar can keep them at just the right temperature to hold onto their flavor and nutrients. Don’t worry about the cold—you can definitely prevent it from freezing up inside if you plan ahead. I’ll break down everything you need to know to get started, step by step.

Why Build A Root Cellar?

Let me just say—there’s something really satisfying about digging into your pantry in February and pulling out a homegrown squash or bag of carrots you stored away in the fall. A root cellar lets you store food without needing fancy electrical storage, like refrigerators or freezers. Plus, it uses the natural coolness of the earth to create a stable environment for long-term storage.

The best part? It’s all about sustainability—lowering your energy use, and really getting in tune with nature’s cycles.

But there are even more reasons: better flavor and healthier produce. Properly stored in a root cellar, many root vegetables can last for months while staying crispy, delicious, and nutrient-rich. Even fruits like apples or pears will keep their sweet-tart flavors for a good chunk of time.

Choosing The Right Location

Now, Robert, you mentioned that you’ve got a spot behind your garage, which could work fine—though we should consider a few things before picking the exact spot:

• Cool but not freezing: The temperatures in Toronto are a bit challenging, especially in January when it can get super cold. Ideally, you want an interior temperature between 32°F (0°C) and 40°F (4°C). You can help regulate this by picking a *north-facing slope*, if you’ve got one, or a shaded spot where the sun doesn’t hit it directly through the day.
• Drainage: No one likes a soggy cellar. You need to make sure the area drains well so no water can seep in. The last thing you want is a flooded root cellar after a heavy rain or when the snow melts in spring. Make sure your spot’s on higher ground if possible.
• Soil quality: Some people overlook this, but the quality of the soil matters. You’ll be digging into it, so chunky rocks, roots, or hard-packed clay could make the work a lot harder than you’d like. Pick an area with well-drained, softer soil if possible.

How Large Should Your Root Cellar Be?

If it’s just you or a smaller family using the cellar, you won’t need a whole lot of room. However, if you plan to go big and store a large quantity of produce (especially bulky stuff like potatoes), you may want to give yourself some decent square footage. Don’t forget to consider headroom too—you’ll need space to walk around comfortably once it’s filled with shelves and produce.

For some loose numbers, a root cellar around 8×8 feet works for most small households. It gives enough room for racks and bins without feeling cramped. If you’re more ambitious, you could go larger. I found that making mine about 8 feet deep and 10 feet wide was perfect for *my* storage needs!

Designing Your Root Cellar: Types To Consider

So, what kind of design should you go for? There are several options depending on your budget, ability to do DIY projects, and the space you have. Here are a few common types:

1. In-Ground Root Cellar (The Classic)

This is the one we all probably picture: digging directly into the ground and then adding some kind of insulating roof or cover. It’s one of the more traditional methods, but also works really well, especially in colder climates like yours, Robert.

• Pros: It’s insulated naturally by the earth, which makes controlling the temperature a lot easier. Plus, the cost is pretty low.
• Cons: Digging can be hard work, especially if you’re doing it by hand. Also, you’ll need to make sure water doesn’t seep in, so a proper drainage system is key.

2. Walk-In Basement Cellar

If you’ve got a basement that’s cool but not totally freezing, you can repurpose part of it as a root cellar. This option involves very little digging, and is ideal if you’re looking for more of a “quick fix.” However, basements can sometimes be a little too warm, so make sure you can isolate the area and keep it properly ventilated.

• Pros: Easier to build, quicker access from your home, and costs less to construct.
• Cons: Not as naturally cool as an in-ground cellar, and may require added insulation to maintain the right temperature.

3. Above-Ground Insulated Cellar

This last design is for those who live in very cold areas or who don’t want to dig at all. You can create an above-ground structure with thick, insulated walls that mimics the temperature regulation of an in-ground root cellar.

• Pros: No digging required and a good option if the ground’s too hard or your space is limited.
• Cons: This type will need more insulation to maintain a steady temperature, and it may not be as effective in naturally cool climates.

Some Common Materials You’ll Need

Once you’ve decided on your design, you can start gathering materials. For most build types, these items are good to have on hand:

• Concrete blocks or lumber: For walls or framing.
• Insulation materials: Straw bales, thick wooden boards, or foam boards are good for this, especially along the ceiling and walls.
• Gravel or sand: For proper drainage in the floor of the cellar.
• Ventilation pipes: Ventilation is crucial to keep the air flowing and prevent things from getting damp and moldy inside the cellar.

Temperature and Humidity Control Tips

Robert, you were asking about keeping the root cellar from freezing over during the Toronto winters, and that’s definitely something to think about. One of the best ways to do this is to insulate—especially on the roof and anywhere directly exposed to outside air.

In addition to insulation, here’s how you can keep the temperature and humidity right where you want it:

1. Proper Ventilation

Ventilation is key to keeping everything fresh. Without proper airflow, humidity can build up, which leads to mold and rotting. But too much airflow, and you’ll let in cold, damaging your produce. A typical setup involves two ventilation pipes: one near the ceiling and the other closer to the ground. This allows for natural air circulation without big temperature swings.

2. Insulate, Insulate, Insulate

We’ve talked about this a bit already, but just to stress it again: Insulation helps regulate temperature. If you go with an in-ground design, adding a thick layer of straw or wood insulation to the ceiling will help. For above-ground designs, using foam board or heavy wood around the walls and roof is necessary.

3. Control Humidity

The sweet spot for humidity inside your cellar is around 85-95%. If you find that the air is getting too dry (which can happen during those cold, dry Toronto winters), consider adding some trays of damp sand on the floor to help balance things out. You’ll also want to ventilate regularly to keep things from getting *too* humid.

Preventing Freezing and Other Common Issues

Alright, Robert, let’s tackle the freezing issue directly. To prevent freezing, the idea is to keep the space insulated enough to prevent dramatic drops in temperature. A few easy things you can try, assuming you’ve already got insulation in place:

• Bury the cellar deep enough to take advantage of the earth’s natural warmth.
• Install straw bales or foam boards around the outer perimeter for extra insulation.
• If space permits, add a small, simple heat source, like a lamp, but honestly—if the design is good, this usually isn’t needed.

And hey, try using old carpets or thick blankets as extra insulation for the cellar door or walls on those really bitter nights—it’s a low-tech but effective trick!

Watch Out For: Mold and Rot

If the ventilation isn’t quite right, you could end up with high humidity, leading to mold—a gardener’s worst enemy! To avoid this, check that your ventilation pipes are working. Also, leave space between your stored produce so air can move through freely.

Final Thoughts…

Robert, thanks so much for sending in your question! A root cellar is a fantastic way to store your crops through winter—and, even with Toronto’s colder climate, I’m confident you can make it work with some insulation and careful placement. Just remember: pick a good location, ventilate properly, and don’t let things get too dry or too cold. You’ve totally got this!