Place the brine ingredients in a small saucepan and bring to a boil over medium-high heat, stirring to dissolve the sugar and salt. Remove from heat and set aside.
Clean green onions, then cut them ½ inch shorter than the height of a ½ pint canning jar. Put garlic and dill into jar, then pack the onions tightly into the jar, without smashing.
Pour brine over onion, place lid and ring on jar and screw on snugly. Let the jars cool to room temperature, then store in the refrigerator. Wait at least 48 hours for flavor to mature before enjoying them.
I am not a health professional and nutrition data is calculated programatically. Accuracy may vary with product selection, calculator accuracy, etc. Consult a professional for the best information.