Seperate leaves and flower petals. Select leaves without brown spots and healthy blossoms.
Sterilize a glass bottle or jar which has an airtight, screw-on, spring or cork top.
Place a substantial amount of leaves and petals, loosely packed, into the glass container. Cover them with light olive oil.
Place in a warm cupboard for at least three days to let the leaves, and petals steep. Some recipes suggest four weeks. Swirl the contents everyday to allow the leaves and flowers to thoroughly infuse their virtue into the oil.
Thoroughly strain out and discard the leaves and petals using cheesecloth. Make certain that you remove all botanical materials or the mixture may later become rancid and "lose its virtue."
If the vervain oil is not intense enough, repeat these steps with the same oil and more fresh leaves and flower petals.
Some herbal authorities suggest setting the jar on the window sill in the sunshine; other say the oil should sit in a dark cupboard.
You will have to experiment, as I've never used this method to make vervain oil.
Some herbal lore insists leaves should be picked before the plant flowers in order to obtain the optimum virtue of the leaves.
Thus, according to these authorities, leaves and petals should not be harvested together. Harvesting the petals is, therefore, a separate operation done at a later date. Hence, some herbal lore would advise against making a mixed leaf and flower infusion as described, and would require you to either make an infusion with fresh flowers or fresh leaves, but not both at the same time.
As with any herb in your garden, you ought not harvest too many leaves off of any single plant or the herb will die.
As I said, I've not personally made this type of oil. At this time, I do not have access to fresh vervain (Verbena officinalis). The method described here is gleaned from several different books. I've included it, because it is difficult to purchase vervain oil. Most oil sold as vervain or verbena is actually lemon verbena (Lippia citriodora), sometimes known as van van. Lemon verbena has a nice lemony scent and lemons are sacred to Diana.
I have only found one place that sells a floral-scented vervain oil and may indeed be true oil of Verbena officinalis. The Crystal Fox, a magical store located in Laurel, Maryland.
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