Tear up about a cup of loquat leaves. Shred them into small, rough pieces about the size of your thumbnail. The smaller they are, the faster the pieces macerate and break down in the maceration fluid.
Slip the shredded leaves into the bottom of a clean glass jar. Clean is very important; the jar will be sitting for a while. If the jar contains bacteria or food residue, your tincture will get moldy. A mild dish soap and lint-free cloth usually does the trick.
Fill the jar to the top with cold, distilled water. Distilled water contains fewer contaminants than tap or rain water, making it less likely to mold or grow algae.
Cap the jar very tightly and put it in a cool, dark, dry place for about three days. Check on the macerate daily and shake it vigorously. This helps break up the weakened leaves even further.
Strain the macerated leaves through cheesecloth, catching the tincture fluid in a clean jar. You may either use this tincture as it is, or add a fresh batch of loquat leaves to make it stronger. Again, consult with a medical doctor before beginning alternative treatment, and if your doctor gives you the go-ahead, consult with an experienced alternative-medicine specialist to discuss dosage. Also visit the National Institutes of Health's National Center for Complementary and Alternative Medicine, for informatoin on this and all alternative medicine.