Begin by lightly crushing culinary-grade lavender buds using a mortar and pestle or the back of a spoon.

In a medium saucepan, add ripe blueberries, honey, lemon zest, and freshly squeezed lemon juice. Stir to combine.

Cook the mixture over medium heat, stirring occasionally for about 10 minutes until the berries soften.

Lower the heat to medium-low and let the mixture simmer for 20 minutes, skimming off any foam.

Use a candy thermometer to check if the jam has reached 220°F (105°C) or perform the wrinkle test.

Gently stir in the crushed lavender buds once the jam thickens.

Ladle the jam into sterilized jars, leaving about ¼-inch headspace, and process in a boiling water bath for 10 minutes.

Allow the jars to cool completely on a clean towel or rack and check seals before storage.