In a large non-reactive pan add the strawberries and sugar. Cover and let stand at room temperature for 1 to 2 hours. Have ready hot, sterilized jars and their lids. You can sterilize by placing in a 225 degree oven on a cookie sheet for 15 minutes or sterilize in hot water or the dishwasher. Place 2 or 3 small plates in the freezer. Add the lemon juice and pectin to the pot. Bring to a boil over medium-high heat, reduce the heat to medium, and cook, uncovered, add lavender, stirring frequently, for 10 minutes. Remove from the heat. Use 1 tsp. jam and a chilled plate to test if the jam is ready. The mixture is ready if it wrinkles when nudged gently with a finger. If it doesnâ€™t, continue to cook for a few minutes longer and retest. Ladle the hot jam into the jars, leaving Â¼ inch of headspace. Remove any air bubbles and adjust the headspace, if needed. Wipe the rims clean and seal tightly with the lids. Process the jars for 10 minutes in boiling water bath. Remove and let cool on a towel. The lids will pop and that means they are sealed. To test, simply press down on the lid and if no popping happens, they are sealed. Tighten the lids and store in a dark, cool location.