Why I Infuse Calendula Oil Slowly

During the Calendula Project, something unexpected happened.

At eight weeks, the carotenoids in the oil hadn’t yet reached full saturation. The extraction was still climbing. When the chemist reviewed the results, she suggested we take the question further.

What would happen if we compared infusion methods?

Instead of only extending time, what if we tested continuous mechanical shaking against the way I’ve been infusing all along — shaking the jars by hand each day?

Not to speed things up. Not to modernize the process. Simply to understand it more clearly.

If you’d like to read the full lab study and methodology, you can find it on the Calendula Project page. What follows here is simply an explanation of why I work the way I do.

The Way I’ve Been Doing It

My calendula oil infusion method has always been simple and consistent.

Each day, I take the infusion jar and shake it for about a minute. Long enough to move all the calendula through the oil. Long enough to make sure nothing is sitting compacted at the bottom or floating dry at the top.

Then the jar goes back to rest, away from light.

The daily shaking isn’t aggressive, and it isn’t hurried. It’s purposeful.

Dried plant material can trap small pockets of air. Petals can clump together. Layers can settle unevenly. When that happens, parts of the plant aren’t fully in contact with the oil. And oxygen — even in small amounts — isn’t kind to delicate compounds like carotenoids.

That brief daily movement helps release trapped air, re-coat the petals, and keep the infusion even. It allows the extraction to unfold steadily instead of unevenly.

Then I let it be still again.

Movement. Then rest

What We Tested

Using the same batch of dried calendula flowers and the same apricot kernel oil, she designed a comparison.

One set of oils was infused with daily hand shaking — the way I’ve always done it.

Another set was placed on a mechanical shaker, moving continuously at 112 revolutions per minute.

Both one-month and two-month infusions were tested. All samples were protected from light and handled carefully before analysis. Each was measured twice for total carotenoid content.

The question was straightforward: would constant motion extract more?

https://video.wixstatic.com/video/4edae8_8fe2c1f6236840b79641d9f300c876b4/720p/mp4/file.mp4

What the Results Showed

All of the oils successfully extracted carotenoids. Calendula did what calendula naturally does.

But continuous mechanical shaking resulted in lower carotenoid levels than the oils that were shaken once daily by hand.

Extending the infusion from one month to two months increased carotenoid extraction for both methods. Time deepened the process.

Constant agitation did not.

Why This Matters

On the surface, it seems logical that more movement would mean more extraction.

But carotenoids are sensitive compounds. Continuous shaking can introduce more oxygen over time and create ongoing stress within the oil and plant material. Instead of preserving what’s delicate, it may slowly diminish it.

The daily minute of shaking that I do isn’t about force. It’s about attention. It keeps the flowers evenly saturated without overwhelming the system.

This study didn’t change my practice.

It clarified it.

Calendula doesn’t need to be pushed.

It needs to be tended.

And that is why I infuse slowly.

For further details, including full methodology and laboratory data, you can read the complete study here: Mechanical Versus Manual Shaking.