What’s The Best Way To Store Onions Or Garlic In A Root Cellar?

“Hey! I’ve got a ton of onions and garlic from this summer’s harvest, and I really want to store them in my root cellar this year. I’ve tried it before, but they either sprouted early or got moldy. What’s the best way to store onions or garlic in a root cellar so they last longer? I’d love any tricks you might have for making sure they stay in good shape through winter.” Thanks, Nancy, Bend, Oregon, USA.

What’s the Best Way to Store Onions and Garlic in a Root Cellar?

Storing onions and garlic properly is an age-old practice, especially for those of us who love growing our own food and need to make it last through the colder months. Root cellars are fantastic, but they do require a bit of care and know-how to store bulbs like onions and garlic successfully. Since you mentioned they molded or sprouted when you tried it before, Nancy, it sounds like there might be a few tweaks you can make to get better results this year. Let’s walk through some tips and tricks to help these aromatics last all winter long!

Why Store Onions and Garlic in a Root Cellar?

The root cellar is traditionally used to store crops through cold weather — it helps maintain a low temperature and moderate humidity, making it ideal for storing most root vegetables, including onions and garlic. Keeping them in the right conditions slows down spoilage, prevents sprouting, and helps maintain their flavor. This means you’re able to rely on your harvest well into the winter months without any fuss.

But without the right setup — and believe me, I’ve had this happen too — onions and garlic can sprout too early, mold, or dry out entirely. To avoid that, we need to look closely at everything from temperature and humidity to storage methods.

Ideal Conditions for Storing Onions and Garlic

Before we get into the actual storing process, let’s nail down the key environmental conditions they need. Onions and garlic can be a bit picky, and finding that sweet spot can make all the difference.

Temperature

Onions and garlic prefer cooler temperatures but not freezing ones. **The ideal temperature range is between 32°F to 40°F (0°C to 4°C).** Too warm, and they’ll sprout; too cold, and they could freeze, which would ultimately degrade their quality once thawed.

During a bad cold snap, I’ve had the corner of the cellar where I stored my onions get below freezing, and they turned to mush by spring. Not fun! If you’re in an area where your root cellar tends to dip below 32°F, you may need to insulate your storage boxes, or even move them to the warmest spot in the cellar.

Humidity Levels

Now, this is super important: onions and garlic like **low humidity levels**, around **65-75%**. This is key to avoiding mold, which can happen when there’s too much moisture in the air. On the flip side, they can dry out if it’s too arid in your cellar, so hitting that mid-point is your goal.

If you’re not sure about your root cellar’s humidity, there are cheap hygrometers you can set up to monitor it. I keep one hanging right by my boxes, next to my thermometer, so I can check the environment at a glance!

Prepping Onions and Garlic for Storage

Before you just toss your onion and garlic harvest into the cellar, a bit of prep is needed to make sure they’re in the best shape for long storage.

Curing is Key

Both onions and garlic need a good, thorough **curing** after harvest to dry them out and help seal the outer skins — this is what prevents rot and sprouting during storage. Without curing, they’ll spoil faster than you can say “roasted garlic.”

Here’s what you’ll want to do:

• **For onions**: After harvesting, lay them out in a single layer somewhere warm and dry (think around 75°F or 24°C) for about **2 weeks**. Keep them out of direct sunlight but let air circulate. Once the skins are papery and the necks (the part where the stem meets the bulb) are shriveled and dry, they’re ready.
• **For garlic**: Garlic takes a bit longer, usually around **3-4 weeks** to cure properly. Hang them or lay them out in bunches, once again in a warm, airy spot, until the outer wrappers are dry and the stems feel brittle.

I remember rushing the curing process once when I got lazy, and boy, did I regret it. My onions sprouted within a month, and I lost about half of them. I’ve learned that patience really pays off here.

Choosing the Right Onion and Garlic Types for Storage

While you can store just about any onions and garlic, some varieties are better suited for long-term storage. Knowing what you’ve planted this year, Nancy, might help gauge how well they’ll do over winter.

• **Hardneck garlic** tends to have a shorter shelf life than **softneck garlic**, but softneck varieties can last upwards of 6 months if stored properly.
• **Storage onions** (like yellow or white varieties) often last longer than sweeter varieties (like Vidalia or red onions), which have higher water content and more sugar.

If you’re growing a variety more prone to quicker spoilage, like the sweeter reds, I wouldn’t store as many and try to use them up by late fall.

Methods for Storing Onions and Garlic in a Root Cellar

Okay, so once you’ve got everything perfect in terms of temperature and humidity, and your onions and garlic are cured, now comes the actual storing. There are a couple of methods you can choose from depending on the space you have.

1. Net Bags or Mesh Baskets

This is one of the simplest ways to store both onions and garlic. **Netted bags** or baskets with plenty of airflow allow the bulbs to breathe and prevent moisture from building up — moisture being the #1 enemy when it comes to sprouting or molding in the cellar.

I hang my net bags in a corner so they’re off the ground and out of the way of any potential damp spots. Pinch the stems together or loosely tie them before hanging. Plus, this makes checking them for mold pretty easy!

2. Braiding Garlic and Onions

For garlic especially, you can keep the stems long and **braid** them together. This not only looks cool hanging in your cellar, but it’s practical too. Braiding will help the garlic stay organized and keeps air circulating around the bulbs. Trust me, it lasts longer like this than when left in a heap.

**Onions** can be braided too, but their thicker necks make it a bit trickier. I’ve tried it a couple of times, but honestly, I find it easier to tie them individually and hang them in bunches.

3. Wooden Crates or Slatted Boxes

For a bulkier harvest, **wooden slatted crates** work wonders. Stick with slatted designs so air can move around the produce. You can layer onions and garlic lightly, but make sure not to cram them in too tightly.

Pro Tip: Use **newspaper or straw** to layer between rows of onions. This prevents them from touching (which cuts down on rot), but still allows some airflow. I’ve heard some people complain about straw harboring moisture, but it’s never been an issue for me as long as the overall humidity is in check.

4. Regular Checks

Regardless of which method you decide to use, a regular **check-up** on your stored onions and garlic is critical! Set a reminder for once a week or so to go through and inspect for any bulbs that are soft, sprouting, or showing signs of mold.

Honestly, I’ve found a bad onion can ruin the whole lot pretty quickly if left unchecked. By pulling any that seem past their prime, you can stop the spread of rot.

Common Problems When Storing Onions and Garlic (and What To Do About Them)

Even with the best prep and storage, problems can pop up. The good news is that most issues have simple fixes. Let’s go over a few of them, Nancy.

Sprouting

**Why it happens**: Bulbs often sprout when the cellar temps are too warm (anything above 40°F). They think it’s time to start growing again!

**What to do**: Try to lower the temperature in your cellar or check if any heat sources (like a furnace or electrical appliances) are radiating nearby. Also, storing them in darker locations can help delay sprouting.

Rot or Mold

**Why it happens**: High humidity (over 75%) is usually the culprit here. Stacking onions or garlic closely together cuts down airflow, which encourages mold growth.

**What to do**: Ensure you’re allowing proper ventilation with net bags, mesh baskets, or slatted crates. Also, periodically switch up the position of the bags or baskets if you notice any dampness.

Drying Out Too Fast

**Why it happens**: Your root cellar might be too dry, causing the bulbs to lose moisture too quickly.

**What to do**: If this is the case, you could try placing a bit of damp sand (not too wet) in the boxes to bring the humidity up slightly. Another option? Move them to a less drafty part of the cellar.

Final Thoughts…

Nancy, thank you so much for sending in this fantastic question! I love seeing how many folks are getting more into food preservation and taking advantage of their root cellars. The key takeaways here are keeping your onions and garlic cool (but not freezing), well-ventilated, and as dry as possible without tipping the scale too far into crispy territory. Get that balance right, and your harvest should stay fresh well into winter.

Just remember, trial and error is all part of the fun. If you’ve had a couple of setbacks before, don’t be discouraged! Each year is a chance to fine-tune the process a little more.