How to Dehydrate Onions

There’s something deeply satisfying about pulling onions from your own garden—firm, fragrant, and full of flavor. But as any homesteader knows, onions don’t always store well for the long haul. Some varieties keep beautifully, while others sprout or soften before you’ve had a chance to use them. That’s where dehydrating comes in.

Dehydrating onions is one of the simplest preservation methods you can try. With just a dehydrator or even your oven set to its lowest temperature, you can transform fresh onions into lightweight, shelf-stable flakes or powder that will last for months. No special equipment required, no need for freezer space, and no worries about spoilage.

Whether you’re looking to stock your pantry with ready-to-use onions for soups and stews, or you want to make your own onion powder without preservatives or additives, dehydrating is a practical, accessible option. And if you’re curious about other preservation methods, don’t miss these related posts:

• How to Freeze Dry Onions
• How to Freeze Onions
• How to Dry Green Onions

Why Dehydrate Onions?

• Shelf stable: No refrigeration required once dried.
• Versatile: Use in slow cooker recipes, soups, and sautés.
• Homemade onion powder: Grind dehydrated onions into powder—no preservatives, anti-caking agents, or packaging.
• Accessible: Works with a dehydrator or even your oven.

Step-by-Step: How to Dehydrate Onions

Using a Dehydrator

1. Prep the onions
   Peel and chop* to your preferred size—rings, slices, or diced.
2. Arrange on trays
   Spread onions evenly on dehydrator trays. Avoid overlapping pieces for best airflow. 
3. Set temperature
   Dehydrate at 125°F–135°F until onions are completely dry and brittle. This usually takes 6–12 hours depending on thickness and humidity.
4. Check for dryness
   Onions should snap when bent and feel crisp, not leathery.
5. Store properly
   Transfer to airtight containers—glass jars or mylar bags work well. For longer storage, use a vacuum sealer to remove air.
   

*You must check out my absolute favorite veggie chopper.  It’s what I use when processing lots of veggies, like onions, all at once.  After years of breaking and re-buying plastic choppers that just didn’t stand up to the abuse from my hardworking homestead kitchen, I went on a quest to find a sturdier model.  I’m happy to report that this handy (and sturdy!) chopper has been going strong for years now, processing tomatoes, onions, peppers, and more.  Highly recommend!

Using an Oven

1. Prep the onions
   Peel and chop as desired.
2. Arrange on baking sheets
   Line sheets with parchment paper and spread onions in a single layer.
3. Set oven to lowest temperature
   Usually around 170°F. Keep the oven door slightly ajar to allow moisture to escape.
4. Dry until crisp
   This can take 6–10 hours. Stir occasionally to ensure even drying.
5. Cool and store
   Once crisp and dry, let onions cool completely before storing in airtight containers.

Storage & Use

• Keep jars of dehydrated onions handy for everyday cooking.
• Rehydrated onions won’t return to their original texture, but they’re perfect for slow cooker recipes, soups, and stews.
• Grind into onion powder for a pantry staple that’s 100% homemade.

Gift Idea

Dehydrated onions may not sound glamorous, but they’re incredibly useful, and that makes them a thoughtful gift for anyone who loves to cook. Package them in a rustic glass jar, tie on a handwritten recipe card for homemade onion powder or a hearty soup mix, and add a sprig of dried herbs from your garden.

You could even bundle a set of spice jars or a small mortar and pestle to inspire creative kitchen use. It’s a gift that’s both beautiful and practical, straight from your homestead.

More Homegrown and Homemade Gift Ideas

• Homemade Fajita Seasoning
• Homemade Herbal Season Salt
• Homemade Ranch Mix
• Homegrown Dried Herbs
• Homegrown Paprika Powder
• Dried Apple Chips
• Dried Tomato Slices
• Homemade Tomato Powder
• Homemade Sriracha Sauce
• Homemade Freeze-Dried Marshmallows
• Homemade Vanilla Extract
• DIY Beeswax Candles
• How to Grow Loofah Sponges