Expert shares simple hack to grow seemingly endless supply of popular produce: 'Unlimited'

The cost of vegetables keeps rising, so it's more important than ever to try to keep those expenses down. 

TikToker Ashley Diedenhofen (@sciencebyashley) has come up with a way to grow green onions forever after you buy a single batch. 

"Never buy green onions again!" she put in the caption.

@sciencebyashley never buy green onions again! #foodwaste #sustainability #greenonionhack ♬ original sound - Ashley Diedenhofen 𓇼

The scoop

Diedenhofen starts by putting the green onions she buys into a container with shallow water. She keeps the water fresh, so anytime it's cloudy or smells like onions, she changes it. 

She recommends pruning back any of the green bits that turn yellow or look dried, but not peeling the onions, so they don't get slimy. 

Over the course of a couple of weeks, the green parts of the onions grow to almost twice the height of the ones she originally bought. Once they get so tall they fall over, she recommends cutting off the green parts to freeze for later use, then planting the roots and the white part in soil. They will continue to grow, and you won't have to buy green onions again unless you want to. 

How it's helping

According to the U.S. Department of Agriculture, the cost of food, including the cost of vegetables like green onions, rose in July and August 2025, and it is expected to continue rising. 

Hacks like this one allow people to save money so they don't have to worry so much about how much food costs. The more food you grow on your own, the less you'll spend at the grocery store. You can use similar methods to grow your own leeks and red onions, too. 

Food hacks like this one also reduce the amount of food waste in landfills. The Environmental Protection Agency notes that waste from what we eat makes up 24% of what's in landfills, so reducing it is important on that side of things, too. 

What everyone's saying

Other TikTokers loved this hack. 

What is the biggest reason you don't grow food at home? Not enough time ⏳ Not enough space 🤏 It seems too hard 😬 I have a garden already 😎 Click your choice to see results and speak your mind.

"I had a green onion that was going well for a few months. I would just talk to it while doing dishes and in return I got tasty green onions!" one shared. 

"I planted some a few summers ago and they grew to about 2.5-3 feet tall. It was awesome unlimited green onion for my food," another said.

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