Begin by grinding the fresh lavender buds using a mortar and pestle until they reach a fine consistency; this should take about 2-3 minutes. Set the prepared lavender aside.

To ensure your jam stays fresh, sterilize three half-pint canning jars in boiling water for at least 10 minutes. Once sterilized, remove the jars using tongs and let them cool on a clean kitchen towel.

In a large skillet, combine the blueberries, honey, fresh lemon juice, and lemon zest over medium heat. Allow the mixture to come to a gentle simmer, mashing the blueberries slightly with a fork or potato masher for about 5-7 minutes.

As the jam mixture bubbles, gently scrape off the foam with a spoon and set it aside.

To determine if your jam has reached the desired thickness, perform the freezer test after about 10-15 minutes of cooking. Place a teaspoon of the jam on a cold plate and return it to the freezer for 5 minutes.

Once the jam has set to your liking, promptly remove the skillet from the heat. Stir in the finely ground lavender.

Carefully spoon the hot jam into your sterilized canning jars, leaving about a quarter-inch headspace at the top. Seal the jars with lids and process them in a boiling water bath for 10 minutes.