1 Rinse the screw-top jars with lids (they should have a total capacity of 800 ml) (approximately 3 1/2 cups total capacity) in a pot of boiling water and then let drain upside down on a kitchen towel.
2 Squeeze out the lemon juice.
3 Halve the vanilla bean lengthwise and scrape out the seeds.
4 Combine the lemon juice, vanilla seeds and apple juice with the jam sugar in a pot.
5 Rinse the rosemary, shake dry and add to pot along with the vanilla bean.
6 Bring mixture to a boil and cook while stirring over high heat until bubbling, 5-7 minutes.
7 Test setting point by placing a few drops of the liquid on a small plate. It should begin to set after a few seconds. If so, then it is ready to be placed in jars. If not, cook for another 1-2 minutes and repeat the test.
8 Remove vanilla bean and rosemary from pot. Pour the hot mixture through a funnel into the prepared jars.
9 Seal jars with lids immediately, then rest upside down on a damp kitchen towel and let stand 5 minutes. before turning right side up to cool completely. Tip: To preserve the jelly for longer, you will need to process the jars according to manufacturer's instructions, or visit http://nchfp.uga.edu/.