Growing scallions hydroponically is exceptionally simple, clean, and fast—perfect for your kitchen. Here’s a set of highly practical steps:

I. The Simplest Method (You Can Grow Them Using Leftover Scallions from the Kitchen)

1. Buy a bunch of scallions, cut off the green tops to eat, and keep the white root end plus 3–5 cm of the white stem.

2. Find a clear cup or glass jar, fill it with clean water, and make sure the water level just covers the roots—do not let the water submerge the white stem.

3. Place it in a spot on the windowsill with indirect sunlight, avoiding direct, intense sun exposure.

4. Change the water every 1–2 days to keep it clean and prevent odors.

5. Typically, new shoots will start to emerge in 3–5 days, and you’ll be able to harvest them for consumption within a week.