First, let’s talk about green onions. Green onions are the green stems that extend above the onion bulb. They are also known as scallions. If we are counting each stem as 1 scallion, you can expect anywhere from 3 to 10 scallions per onion bulb.
If you are trying to grow green onions from an onion bulb, keep in mind that they are harvested long before regular onions are. Green onions can be harvested when they are about 5 inches in height and at least 6 millimeters in diameter (The diameter of a pencil). Ideally, you just want to harvest them before the onion bulb begins to form.