Answer: Timing is key when harvesting lavender flowers for wands, dried everlastings, potpourri, and oil production. The best time is following a few days of dry weather, during the late morning after any dew has evaporated. Picking lavender flowers during dry weather shortens the drying process because the stalks will have less water in them. The cooler morning air temperature is important because lavender oil dissipates as the temperature rises. Also, as the day wears on, there will be more bees to contend with. I do not harvest flowers on rainy days, as many of the constituents of the essence of lavender are water soluble and will leech out.
When harvesting flowers for everlastings, I check the dark flower heads daily and collect them only at the swollen bud stage, when just one or two of the flowers have opened on the flower head. Picking the flower heads at this time preserves their dark color and ensures that the flowers will stay attached to the stalk once dried. Picking flower heads once they have passed this stage results in paler flower colors and shattered flower heads.
When harvesting lavender for potpourri, I'm less concerned about shattered flower heads and flower colors than I am when collecting flowers for drying on the stalk to make everlastings. I don't harvest white or pink flowering varieties for drying on the stalk, as their colors turn muddy when dried. However, they are fine for potpourri or sachet making.
Enjoy your harvest!
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