Dip the rosemary or thyme sprigs into boiling water for 2–3 seconds, rinse under cold water and pat them dry with paper towels. Set aside.
Pour the apple juice stock into a large, heavy-based saucepan, add the sugar and the larger herb sprigs and stir over low heat until all the sugar has dissolved. Remove the herbs and bring to a full rolling boil for 5–10 minutes. Remove the pan from the heat and test if setting point has been reached. When the jelly will set, put the small herb sprigs into clean, warm jars, then pour in the jelly. Cover, label and date the jars, and store in a cool, dark, airy cupboard.