To Prepare Juice Wash plums well. Crush fruit, add water, cover and bring to a boil over high heat. Reduce heat and simmer 15 to 20 minutes or until fruit is soft. When fruit is tender, pour everything through a double layer of dampened cheesecloth or a damp jelly bag.

Suspend the bag over a bowl or pan, using a stand or colander to hold the bag. Drain the juice without pressing or squeezing, which will cause cloudy jelly. If a fruit press is used, the juice should be restrained through a jelly bag. To Make Jelly Sterilize canning jars .

Cook juice down until thick and cherry colored. Measure juice into a saucepot, add sugar and stir well.

Boil over high heat until the temperature measures 8 degrees F above the boiling point of water (220 degrees F at sea level), or until the jelly mixture sheets from a metal spoon. (See Testing Jelly Without Added Pectin .) Remove from heat; skim off foam quickly.

Pour hot jelly immediately into hot, sterile jars, leaving 1/4 inch headspace. Wipe rims of jars with a dampened clean paper towel; adjust two-piece metal canning lids. Process in a Boiling Water Canner .

Processing: Process Hot, Half-pints or Pints, boiling-water canner, 0 - 1,000 ft - 5 minutes.

Altitude-adjusted processing table: Table 1. Recommended process time for Plum Jelly in a boiling water canner. / Process Time at Elevations of / Style of Pack - Jar Size - 0 - 1,000 ft - 1,001 - 6,000 ft - Above 6,000 ft / Hot - Half-pints / / or Pints - 5 min - 10 - 15