The next step in my calendula salve project was to make the calendula oil. I needed dried calendula flowers, a carrier oil (I used 500 ml of sweet almond oil) and glass jars. It is a simple process: Fill the glass jars with the flowers (about 2/3 to 3/4 full) and top them with the oil. There should not be much room between the oil surface and the lid as contact with air can make the oil rancid.

I initially used non-standard jars that held a bit more than a cup each. But I miscalculated the volume and ended up having to switch to smaller jars half-way in the process to make the oil fill all the way to the top (to minimize exposure to air). As I had already covered the flowers in the initial jars with oil, in the end, my jars held more flowers than intended. This will make the oil more potent, but also potentially will yield less oil as some of it will be absorbed by the flowers.

I let the oil infuse for about 6 weeks in a warm, dark place (under a cardboard box next to the radiator in my dining room), turning the jars every couple of days.

After those six weeks, I strained the oil using a sieve lined with one layer of cheese cloth. I tried to squeeze out as much of the flowers as I could.

In total, infusing the flowers with just under 16 oz. of almond oil yielded 12 oz. of calendula oil. As expected, some of the oil (a surprising amount, actually) had been absorbed by the flower petals and the cheese cloth. I then stored the oil in a dark bottle in a dark corner of my cool bedroom for a few days. The oil can be stored this way until the original expiration date of the carrier oil. Onto the next step: calendula salve.