First, cut off the stem and tail of each piece of citrus.
Next, slice each piece of citrus twice, 3/4 of the way down from the tops making an X. Do not cut all the way through. (Watch the video to see how to make the slices.)
Take the first jar, and sprinkle about a tablespoon of salt on the bottom.
If you want to add any herbs or spices, place them at the bottom of the jar. (Watch the video for an example.)
Starting with the lemons, fill the cavity of each lemon, one at a time, with salt, and then place the lemon to form a layer into the first jar. After each layer of lemons is placed into the jar, squeeze them in as tight as possible and sprinkle them with salt before proceeding to add the next level of lemons. Repeat the process until you can fit as many lemons as possible in the jar. Be sure to press down on each layer of lemons as you fill the jar. After you have completed filling the jar with lemons, put a lid on the jar.
While you were packing the jar, the lemons should be releasing juice to be covered with lemon juice. If they are not completely covered, wait a few days. When you check on them, if they are not yet covered with lemon juice, you can add additional lemon juice to make sure all the lemons are submerged under the juice.
Store jar in a pantry or cupboard, out of direct sunlight, for 30 days.
Repeat this process with the limes and the mandarin oranges.
After 30 days, transfer preserved citrus jars to the refrigerator. The preserved citrus will last up to six months while refrigerated.