It is wonderfully easy and inexpensive to make your own infused oils, using herbs you’ve grown or wild-crafted or gotten from a supplier, and oils you can find in any food store.
Making your own is a considerable saving over buying it.
You can use infused oils as-is for skin care and bath oils, or as the base for salves, lotions, scrubs, and other products.
I prefer to use fresh plant material for infused oil.
I believe you get more of the herb’s constituents that way.
Exceptions where I will use dry herbs are:
If you are harvesting your plant material the best time is late morning.
Make sure that your plant material is dry - in other words, there is no rain, dew, or sprinkler spray on it.
Moisture can cause mold in your oil.
Therefore, do not rinse! If you must, your plant material needs to be completely dry before you put it in oil.
When you get home, let your plant material “fresh-wilt” for a few hours or overnight, or place in a very low-temp oven (175o) for a short time. This gets out some of the moisture, so your oil is less likely to mold.
Next, coarsely chop or cut up your plant material. It doesn’t have to be really small, but it shouldn’t be really large pieces, either. You want the oil to have lots of access to the plant material.
Now lightly pack your plant material into a clean, dry jar just to the bottom of the lid ring. You don’t want to pack it tightly, but you also want more than a few sprigs of herb. The plant matter should be slightly springy.
Pour the oil in and fill the jar to a little above the top of the plant matter, then take a chopstick or utensil and stir to get air bubbles out. Make sure the plant material is completely covered with oil. Any plant matter that is above the oil can mold.
Screw on the lid.
Label your jar with the date, the herb, and the kind of oil you used.
Check the jar in 24 hours and top-up the oil if necessary, because the plants may have absorbed some and the level may have dropped.
Put your jar in a warm place to macerate (soak).
The heat helps the oil extract the oil-soluble constituents from the herbs.
Put your jar on a sunny windowsill or another warm place. Always put it on a plate or something oil-resistant! Some of the oil will inevitably ooze out of the jar and can cause problems.
You can also put your jar out in the garden or a plant container, among your plants, to let the sun and earth add their energies. I particularly like to do this with sun-loving herbs like St. John’s wort and comfrey.
Let this mixture soak for six weeks, checking it occasionally. Some herbalists say that a few days or couple of weeks is enough, but I believe that six weeks gives lots of time for the oil to pull out all of the plant’s constituents, and to really absorb the energy of the plant.
After six weeks, strain out the plant matter.
Use a couple layers of cheese cloth or clean muslin, or a fine-meshed strainer or colander.
I like to put a couple layers of cheesecloth in a strainer. Don’t use a coffee filter or paper towels, the pores are too fine and will clog up, and then you’ll be waiting all day for your oil to strain.
Squeeze any leftover oil from the plant matter with your hands or a spoon. (You can put the spent plant matter in your compost or fireplace or trash.)
Put your infused oil into another clean, dry jar. Label this jar also.
Notes: If you have problems with mold forming, you can rescue your oil.
Skim off the top part that is moldy, and if the rest of your jar smells o.k., top-up with more oil and follow directions below.
To deal with a very moist herb or mold: Instead of putting a lid on your jar, use a paper towel or a couple layers of cheesecloth or clean muslin on top of the jar. Hold in place with a rubber band or the rim of a 2-part canning lid. This keeps the oil clean while allowing the moisture to evaporate.
If you have an herb that you know is moist and may have mold problems, then do the above from the start. Don’t set outside, however!
Some herbs don’t take well to fresh-wilting. Dandelion flowers, for instance, tend to continue to go toward the white, pre-seed stage, so I put them in oil right away.
If you are using brand-new muslin, you must wash it first because it has finishing chemicals on it.
Cheesecloth doesn’t because it is meant for food use.
Labeling is important because it assures that you know what herb/s and what oil/s you used.
Don’t rely on your memory, my experience has proven that it is notoriously forgetful!