My very first projects as a new herbalist involved several attempts at oil infusions. I remember I poured olive oil over a jar of dried hibiscus petals and crossed my fingers, hoping that whatever I used it in would be potent and medicinal. I left it for weeks with absolutely no colour change, no scent extraction, and no signs that the oil had extracted anything at all. I felt defeated, but later that month I made a heated oil infusion using sweet almond oil, castor oil, and dried lavender; this time, the oil was fragrant, had a slight colour change, and I felt more confident in my abilities to extract phytoconstituents. Fast forward to about a year later, and I’ve made some beautiful oil infusions with progressively more successful results. I’d love to share what I’ve learned with you, and how you can make potent oil infusions from the very beginning.
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Choose the Right Herbs for Oil Infusions
When I set out to make Hibiscus infused oil, I didn’t really have a reason besides wanting a pinkish oil with a light fragrance. I had an abundance of hibiscus flower tea that I wanted to use up, as I was excited to get started on my herbal journey. I figured I would look up the uses of hibiscus oil later and it would all work out. Unfortunately, this “make now, think later” approach can lead to a lot of waste when it comes to herbalism. Not only did I neglect to have a plan for my oil infusion, which could have lead to it expiring before I could use it, I also could have chosen a better oil for my needs and learned the best ways to extract hibiscus’ phytoconstituents–had I made a plan first.
Some hibiscus phytoconstituents can be extracted with oil, but most of the time hibiscus is best used in water-based extractions that you consume as a tea or glycerite. The colour, for one, is going to be much stronger in these types of extractions. Hibiscus extracted in oil is usually used for hair and scalp care, as well, meaning I could have chosen an oil better suited for use on my fine hair type, such as sweet almond oil or argan oil, even if I wasn’t sure exactly what i was going to use it for.
Had I known that making hibiscus oil infusions is best done over low heat, I wouldn’t have left it in a jar for three months and waited for something to happen. I would have infused it over heat right away and had my oil ready to go almost immediately. It would have been a weak infusion, but I could have used it and perhaps gotten some benefits from it. If I remember correctly, I ended up tossing that oil, afraid it had gone bad over the last three months of failed extracting. Now I understand that dried herbs left in oil rarely go bad before the oil expires, especially when oil infusions are left in a cold, dark basement cupboard. So it became a waste of oil, time, and herbs.
Understanding Herbal Energetics
I have a book that I now use to determine if an herb will be extracted well in oil before I throw an infusion together! It’s called The Modern Herbal Dispensatory by Thomas Easley and Steven Horne. On page 63, there’s a handy chart that shows the best extraction method for different types of herbs. It uses the herbal energetics pattern as each category. From this, I learned that aromatic herbs are especially good for infusing into oil, while herbs like hibiscus, which tend to be considered sweet, bitter, and sour in terms of energetics, do best in water-based extractions. This is because hibiscus’ phytoconstituents (tannins, flavonoids, anthocyanins, alkaloids, saponins, and more) are mostly water soluble. They typically make poor oil infusions. Instead of using hibiscus or another herb in the sweet, bitter, and/or sour energetics category, I’d be more inclined to choose something aromatic for an oil infusion nowadays. Not only would I get a more potent infusion this way, but I’d also be wasting less of an herb’s valuable medicine by extracting it in the proper menstruum!
You can figure out what energetics category an herb is a part of by looking at its phytoconstituents. Phytoconstituents are compounds within an herb that have specific qualities that can be used as medicine. Simply search for your herb’s phytoconstituents online to bring up a page describing exactly what’s in it. Again, I use The Modern Herbal Dispensatory‘s wonderful explanations of these phytoconstituents to deduce what kind of herb I have. Chapter one explains which phytoconstituents belong to which category, as well as what they do. It’s worth keeping in mind that many herbs belong to multiple categories! This means that some phytoconstituents may be extracted well in one menstruum while others may be better suited for another. Make sure you know which phytoconstituents you are trying to extract before choosing a menstruum for herbs like this!
Using the Right Ratio of Herbs to Oil
Another issue I encountered when trying to make oil infusions was being uncertain as to how much of an herb I should use. I tried measuring them out, but usually ended up with my herbs soaking up most of the oil, leaving me with very little usable oil. Instead, I now use a more intuitive approach. I typically fill my jar about 1/2 to 3/4 of the way with my herbs and cover with oil. If the herbs are particularly well-powdered, I will use less. If they’re bulkier, like lavender buds for example, I use more.
I recommend trying out the ratio method for yourself, using different amounts to see what works for you. It’s worth experimenting with to see if you enjoy it, and to standardize your preparations. When making formulations for others, I always measure out my herbs after I fill my jar, and measure the amount of oil that goes on top so I can replicate the results or adjust them if needed. In this way, each herb has its own standardized ratio in my personal practice. I use this kitchen scale to measure all of my ingredients, and always measure by weight instead of volume.
Prepping Your Herbs
Using the freshest herbs possible is going to give you the most potent oil. While you can technically extract fresh herbs in oil, the water content inside of them will eventually cause your oil to grow pathogens. Without a preservative, water will get gross, even when it is in the same jar as oil. Unfortunately, oil and water do not mix. Unless you have an emulsifier and a preservative, there’s no way to ensure oil infusions prepared with fresh herbs are safe to use after about a week in the fridge. Instead, purchase or dry your own whole herbs and store them in a dark, cool place for up to two years. I err on the side of one year or less when I want the most potent oils possible, and tend to use them up long before then, anyway. I love to get my herbs from Mountain Rose Herbs whenever possible, as every herbal product I have ever bought from them has been incredibly fresh and potent. I have also used and enjoyed herbs from Starwest Botanicals and Frontier Co-Op on Amazon!
You can store them in any container as long as they are protected from light and heat. I prefer to use amber jars like these, but clear glass jars inside of a box or cupboard are also perfectly useable options.
I always make sure to macerate (chop) or grind my herbs right before I use them. This increases the surface area available for the oil to penetrate. More phytoconstituents will be drawn out this way, and it will lead to a more potent oil overall. By powdering or macerating your herbs right before you make an oil infusion, you are exposing parts of the plant that could have otherwise been oxidized or degraded over time had you bought them pre-ground. This practice is particularly important for herbs high in antioxidants, which tend to fade in potency quickly after their phytoconstituents are exposed to air. Black pepper is a wonderful example of this! If you currently use pre-ground black pepper, try out a freshly ground peppercorn and compare it with what you have on hand. I guarantee you’ll notice a difference in taste. This concept is easy to push to the sidelines, but may make all the difference in the potency of your oils!
Another practice you can use with herbs that extract better in alcohol (or have alcohol-soluble phytoconstituents) involves soaking herbs in a small amount of alcohol before infusing them in oil. Simply soak for a minute, strain them, and add them to your jar. The alcohol won’t mix with your oil, so you’ll have to shake it well before use, but it won’t hurt your oil either. Alternatively, you can allow them to dry before adding them to your oil. The idea is that the alcohol-soluble phytoconstituents are now extracted and loosened out of their original home, and may combine with the oil more readily.
Infusing Your Herbs
As I mentioned in the very beginning, I’ve been experimenting with different ways to make oil infusions! I have found that the best extraction method involves using very low heat over a long period of time. Using low heat is vital to the preservation of all the phytoconstituents you are extracting, since many of them can be destroyed in the presence of high heat. To avoid this, you can use a double boiler or a pseudo-double boiler like I do. I like this method more than the cold infusion method because the heat helps expand the plant matter and allow oil to saturate it more fully. This leads to better extraction. I feel like this method is a better use of the plant’s medicine, and doesn’t lead to nearly as much waste!
It’s a very simple process and one I like to do overnight. All I do is put my herbs and oil in a jar using all of the tips I shared above, screw the lid on tightly, and place it in a crockpot using the “keep warm” setting. I fill it up with water to about halfway up the jar and put the crockpot lid on top. I then leave it on overnight and strain it in the morning. The water never boils, and the phytoconstituents of my oil infusions are always extracted so well! Below is a before and after shot of hempseed oil infused with calendula.
If you don’t have a crockpot, you can also use a double boiler or simply stick your sealed jar of herbs and oil into a pot of simmering water for the same amount of time. Definitely keep an eye on your stove, and don’t leave it on overnight. Add water as needed if it evaporates too much. I like to keep the water at about halfway up my jars for this method, and check up on it every half hour or so.
Storing Your Herbal Oil Infusions
After you are finished, your oil infusions should have a definitive colour change, and potentially some fragrance as well. Bottle them up in amber jars or dropper bottles and try to avoid leaving head room to keep your oil from oxidizing. Label with the date, expiration date of your oil, and the contents. Keep in a cool, dark place, and use as desired!
I hope these tips will help you to confidently create gorgeous oil infusions. There is definitely an art to it, and I am so happy to have mastered it myself! Don’t forget to like, comment, and share this article to help others learn what I have, too! Thank you so much for reading and supporting my blog! You can find some affiliate links and my socials below if you’d like to support me further at no extra cost to you!