What is a Herbal Essential Oil?
One of the best things about growing herbs is the aromatic smell they give off as you brush by them or sit next to them in the garden in the late evening or early morning. But this aromatic experience can also be enjoyed outside the herb growing season by using herbal essential oils and herbal infusions around the home.
Herbal essential oils contain the concentrated essences (i.e the aromatic chemicals) of your herbs. Essential oils can be used for cooking (e.g. basil oil for salad dressings and stir-fries), as healing ointments (e.g. garlic oil as a lineament) and as bath lotions and aromatherapy treatments (e.g. rosemary oil).
Herbal infusions contain the same aromatic ingredients dispersed in a solvent, generally oil. Herbal infusions can be strong, but they are still diluted not concentrated.
In this article I’ll explain how you can extract the essential oils from herbs using the infusion process. It’s possible to make small quantities of the concentrated herbal essential oils at home, but to make larger quantities you’ll need to harvest lots of herb plants and invest in specialized equipment. As most of us have neither the money or time to do this it’s best to buy the small bottles of concentrated essential oils. These bottles are not as expensive as they used to be because of the revival of interest in herbs. They are easily obtainable online from Amazon or from health food shops.
The History of Aromatic Oils
Making essential oils from herbs has been carried out since ancient times. Hundreds of years ago herbal essential oils were widely used in the Far and Middle East, Egypt and China. In India they formed the basis of a system of traditional medicine that dates back to 1000 BC.
But you don’t need to be be a student of history or a chemist to extract the essential oil form your herbs. In this article I’ll explain how in a few simple steps you can make your own herbal essential oil infusions with easily available and inexpensive equipment and ingredients.
Making Essential Oils from Herbs – Harvesting Your Herbs
To make a herbal oil infusion from your herbs you’ve got to be careful about how you harvest your herbs. For really enthusiastic herbs gardeners the process of harvesting herbs to make essential oils is almost a ritual!
The harvesting should be carried out when the volatile essences of the herbs are at their highest, which is between the time just before flowering up until the time the flowers are half open (although there are exceptions to this). Carry out the harvesting before the sun is fully up, and just after the dew has dried.
If you are harvesting annual herbs for making essential oils from herbs, first cut off the leaves of your herbs to within four inches of the ground. Don’t worry about killing your herbs when you do this. As long as you have left a sufficient number of leaves left on your herbs they will soon grow new leaves to replace those that you’ve harvested.
All your leafy annuals can be cut several times in this way during the summer months. Treat perennial herbs differently though. Don’t harvest them until the end of September.
As you cut your herbs spread them out on a flat surface. Don’t let them get squashed, compressed or bruised in a bag or box, because this will diminish the quality of the herbal essences you produce. Wash off any dirt with cool water, but don’t let them soak in the water. When you have washed them lay them down flat to dry.
If you want to use flowers for making essential oils from herbs (e.g. lavender oil) using the infusion process, harvest the flowers when they are fully open and don’t wash them. To make aromatic oils from seeds such as dill and fennel, collect the seeds when they turn brown and start falling off the dead flowers when touched. To prevent the seeds falling to the ground cut the flowers carefully near the top of flower stem or place a small plastic bag over the flower head.
Extracting the Essential Oils from Herbs
The process of extracting the aromatic herbal oils from your herb plants at home is is called infusion because the herbs are treated so that their herbal essences “infuse” the oil in which they’re immersed.
For this reason essential oils are often called herbal infusions. (The concentrated herbal essential oils that can be bought in the shops can only be prepared economically in large quantities using lots of herb leaves, stems or roots using industrialized processes and expensive equipment).
There are some important things you must bear in mind if you want to produce high quality herbal infusions:
- Use good-quality, mild-flavored oil such as sunflower oil. You don’t want the taste of the oil to compete with the flavor and smell of your herbs. For this reason you should avoid using extra virgin olive oil.
- Cover you herbs completely with oil during the infusing process. Any bits sticking out will oxidize and spoil the flavor of the oil
- Before storing the oil make sure you have removed all the plant material. If you don’t the oil will become cloudy and sour.
There are four main steps you need to follow to make your herbal infusions:
- Put a handful of your herbs or flower heads into a clean glass jar. Choose either a single herb such as basil or a mixture such as oregano, rosemary and thyme. Crush them to release the flavor of the essential oils
- Pour the mild vegetable oil (400 ml) into the jar until the leaves or flowers are completely covered. Put a well-fitting top on the jar and let it stand in a warm (but not sunny) place
- After a week, strain off the herbs (use a cotton muslin cloth or an old open weave linen handkerchief) and then repeat the process of infusion with a fresh handful of your herbs (but using the same oil). Do this as many times as necessary until you have a jar of strongly flavored aromatic oil
- Store your aromatic oil in a small to medium-size sterilized bottle and label it. Tie a small strip of cotton cloth around the top to help reduce the chances of air getting into the bottle. Make sure that you keep your stored oils out of the sun
Here’s an interesting video describing how professional chefs use essential oils:
Now Experiment with Your Preserved Herbs
Once you have prepared your herbal infusion you have around six months to use them before they are past their best. This isn’t the case for the concentrated essential oils that I mentioned above. They will last much longer.
In this article I have only provided a few suggestions on how to use your herbal infusions. If you are particularly interested in herbal health treatments read my article on “Herbal Treatments Using Essential Oils”.
Once you have several bottles of different herbal infusions carry out some some research to find out how making essential oils from herbs and herbal infusions can provide you with the ingredients you need to enjoy the benefits of herbs widely around the home, not only in cooking, but also in bath and skin lotions and soaps and for aromatherapy.
Happy herb gardening,