Process of Plant Infusion
Drying Herbs- for culinary use or as herbal teas. After you harvest the plant materials, you can either place them in a basket with a cloth or paper towel in the bottom to soak up any moisture, hang them up, or put them into a paper bag. Once they are well dried, put them into a glass jar and label them. It is best to store dried herbs in a dark and cool environment to prolong their shelf life. These dried herbs can be utilized throughout the year as tea, spices, infused oils, ground up for facial products, or distilled for hydrosols and essential oils.
Infusion or Maceration is another method of extraction used for plants and herbs, typically used for non-aromatic plants. Although, I have successfully infused many dried aromatic plants from my botanical garden, including plants like German chamomile (Matricaria recutita), Lavender (Lavandula angustifolia), and Yarrow (Acheilia millefolium).
Examples of Infused Oils:
Arnica (Arnica montana) flowers are used in the maceration process, while the roots of the plant are used for homeopathic remedies. Arnica oil is useful as a compress, when used as soon as possible, on injuries with unbroken skin. Arnica oil is one of my favorites to reduce pain and inflammation for fractures, sprains, bruises, strained muscles, tendons, contusions, and swellings. It is excellent to use in a massage oil blend to reduce muscle and joint inflammation.
Precautions: Arnica oil should only be used externally, not internally. Do not use it on cuts or open wounds. It is best not to use arnica during pregnancy or while nursing. If taking blood-thinning medication, consult a physician.
Calendula (Calendula officinalis) has incredible anti-inflammatory and vulnerary properties; it is found to be particularly useful for imbalances of the circulatory system. Its anti-inflammatory properties make it useful in balms and salves for wounds, bruises, bedsores, and skin rashes. The infused oil is excellent for skin care, particularly eczema. In addition, it is a perfect hydrosol to add to skin care products.
Rosehip (Rosa canina) is exceptional for tissue regeneration and for conditions such as facial wrinkles, premature aging, burns, and on scars following surgery. Rosehip’s ability for skin regeneration and repair is due to high levels of both gamma-linolenic acid (47.4%) and linolenic fatty acids (33%). These seeds also contain high levels of vitamin C, which assists the immune system and reduces the stress response.
St. John's Wort (Hypericum periforatum) is useful as an anti-inflammatory, for wounds, mild burns, soothing inflamed nerves, hemorrhoids, varicose veins, sores, ulcers, muscles, or organs in spasm, as well as sprains, or bruises. The infused oil has a red color with a light scent, and is fairly gentle to the skin. It seems to also have a beneficial effect on reducing stress and anxiety.
Use 5-10% in an aromatherapy blend with other carrier oils and essential oils.
Photosensitivity caution: Do not apply before going into the sun.
Process of Oil Infusion
Oil Infusion Process:
STEP 1- Dry the flower heads, herbs, or plant material for a day or two.
Method- Dry plants by putting them in a basket with a cloth or paper towel in the bottom to soak up any moisture, hang them up or place them in a paper bag.
* This year was the first time that I infused St. John's Wort oil with the daily fresh-picked flowers. It was an experiment to see if more of the hypericin would be present. The hypericin is what gives the oil its red color and is apparently responsible for the antianxiety effect of St. John's wort.
STEP 2- Once the plant material is dry, you then chop, crush, or grind it into small pieces or powder. You can infuse just one plant or a combination of plants like German chamomile (Matricaria recutita), rosehip (Rosa canina), and calendula (Calendula officinalis).
STEP 3- Place the plant material into a glass jar and cover it with a base of either organic olive (Olea europaea) or organic jojoba (Simmondsia chinensis) oil. Both oils have a very long shelf life and will not go rancid. Jojoba (Simmondsia chinensis) is the best choice for delicate and aromatic flowers. Remember to use a label with the ingredients and date of infusion.
STEP 4- This mixture is then left in a dark, warm environment for four to eight weeks, shaking the mixture daily 100 times, until the base oil has absorbed the properties and essential oils from the plant material. When you see the plant matter start to degrade it is time for the next step.
STEP 5- Drain off and filter the plant matter, using a funnel and strainer. Use an additional paper filter or cheesecloth if there are any small particles of plant matter.
STEP 6- Bottle - It is always best to store the finished product in a dark amber bottle.
STEP 7- Label- Include the common and botanical name of the plant and the date of final processing and filtering.
Alcohol Infusion: With this process, you can use freshly harvested plant material and do not have to dry it first. This process is typically utilized for non-aromatic herb plants like Motherwort (Leonurus cardiac) and Echinacea Root (Echinacea purpurea) used as an herbal tincture. Follow the same instructions for the oil infusion.
Chemistry of St. John's Wort: Hypericin and Hyperforin; https://pubs.acs.org/doi/10.1021/ed081p1450; Retreived10/06/2022
Comparison of German St. John's wort products according to hyperforin and total hypericin content; https://pubmed.ncbi.nlm.nih.gov/11486982/ ; Retreived10/06/2022
Clinical use of St. John's wort; https://www.uptodate.com/contents/clinical-use-of-st-johns-wort/print ; Retreived10/06/2022