Pickling watermelon rind is a two day process. On the first day, prepare the rind by removing the green part, and cutting the rind into chunks. Place the rind in a pickling crock or a plastic bowl. Cover it with a brine made from one quart water, and 1/4 cup pickling salt. Place a plate on top and weight it down to keep the rind submerged. Allow it to sit in a cool place over night.
On the second day, drain and rinse. Cover the rind with fresh water. Boil until it is soft, and drain again. Meanwhile make a syrup of 1 cup vinegar, 1 1/2 cups sugar, and 1/2 sliced lemon. heat and stir until sugar is dissolved. Add the rind to the syrup and cook until the rind is translucent.
For each pint, place 1 cinnamon stick (about 2 inches long), four cloves, and 3 allspice berries in the jar. Use a slotted spoon to add the rind. Cover with syrup leaving 1/2 inch head space. Process pints in a water bath for 10 minutes. For quart jars, double the spices and process for 15 minutes.
High altitude instructions
1,001 - 3,000 feet : increase processing time by 5 minutes
3,001 - 6,000 feet : increase processing time by 10 minutes
6,001 - 8,000 feet : increase processing time by 15 minutes
8,001 - 10,000 feet : increase processing time by 20 minutes