How to Make a Medicinal Oil


In the spring and summer I gather medicinal herbs, berries, barks, roots and flowers from the woods, river banks and fields.  I let them dry for a day to remove moisture which can cause the oil to become rancid, then I find a mason jar to put them in and I cover them in a good quality vegetable oil and let them sit for a few weeks.  In the winter I buy good quality dried herbs and use this method to extract medicinal qualities of the plant. 


Gathering plants should be done with care.  I avoid over-harvesting by taking a little of what I need here and there rather than taking everything from one patch.  I put the plants in a paper bag or a small basket as this is a better drying environment than a plastic bag.  Once I get home I clean off bits of the plant (and bugs) that I don’t want in my oil and then lay them out to wilt and remove excess moisture.

Here are the steps to making a solar infused oil, suggested by Rosemary Gladstar in her book ‘Medicinal Herbs’:

1.    Place the wilted/dried herbs in a widemouthed glass jar and cover with an inch or two of high quality vegetable oil (preferably olive).  Cover tightly.

2.    Place the jar in a warm, sunny spot and let the mixture steep for 2 weeks.

3.    Strain out the herbs, using cheese cloth or muslin.

Rosemary says, “Because oils generally go rancid quite quickly when exposed to heat and light, you would expect these solar-infused oils to spoil within a couple of weeks.  However, as long as herbs are infusing in the oils, they don’t go rancid.  Once poured and strained, they are as susceptible to rancidity as any oil, but during the actual steeping they remain stable.  I’ve never met anyone who could explain this phenomenon to me, so I have to assume it’s something to do with the antioxidant properties of the herbs.  I do know that this is the way our ancestors made oils, and it has worked wondrously for centuries.”