If you have a bounty of sour cherries, preserving them is an excellent idea. The time it will take is well worth the wonderful taste of the finished product. Sour cherries make particularly tasty preserves. Since you will be controlling the ingredients, you can ensure that your sour cherry preserves will not contain any artificial ingredients. The most time-consuming part will be pitting the cherries, but the actual preserve-making process is fairly straightforward.
Sterilize the jars in a hot water bath before using. To do this, separate the jars and lids. Bring them to a boil in a pot on your stove. Boil for at least 10 minutes.
Pit the cherries using either a cherry pitter or a small paring knife. To do this, slice into the cherry, pull out the pit, and discard.
Bring cherries, sugar and the juice and rind of one lemon to a boil in a large, nonreactive pot. Stir often with a heat-proof large spoon to prevent sticking or burning.
Stir in pectin and butter and bring back to a boil for one minute. Do not overboil or the pectin will break down and the preserves will not set.
Spoon preserves into sterilized jars, leaving a half-inch of headroom at the top of each jar. Secure lids to all jars.
Process all jars in a boiling water bath on the stove to seal them.
Cool the hot jars of cherry preserves on a rack or towels before storing.