Making calendula extract at home involves soaking dried flower heads in a solvent, most commonly olive oil or high-proof alcohol, for several weeks. The process is straightforward and requires no special equipment, but the solvent you choose determines which beneficial compounds you pull from the flowers and how you can use the finished product.
Choosing Your Extraction Method
Calendula flowers contain a wide range of active compounds: flavonoids, carotenoids, triterpenes, phenolic acids, and saponins. No single solvent captures all of them, so the best method depends on what you plan to do with your extract.
Oil infusion is the most popular choice for skincare. Oil dissolves the carotenoids (the orange pigments responsible for skin-soothing effects) and triterpenic alcohols effectively. The finished product works as a balm, salve base, or massage oil. Olive oil is the standard carrier, though jojoba and sweet almond oil also work well.
Alcohol tincture extracts the flavonoids and phenolic acids more efficiently than oil does. These are the compounds with the strongest antioxidant and antimicrobial activity. A tincture is concentrated, taken in small doses internally (diluted in water or tea), or added to sprays and toners for topical use. You need 80-proof vodka at minimum, though 100-proof pulls more compounds.
Glycerin extract is an alcohol-free alternative sometimes used for children’s products or sensitive skin formulations. Glycerin is a weaker solvent than alcohol, so the resulting extract is milder and captures fewer active compounds. It works best as an addition to lotions or creams rather than a standalone preparation.
Preparing the Flowers
Dried flowers are strongly preferred over fresh ones for oil infusions. Fresh petals contain moisture that can introduce mold into an oil-based extract, ruining the entire batch. Make sure the entire flower head is thoroughly dry before you begin. If you’re drying your own harvest, spread the flowers in a single layer on a screen or drying rack in a warm, well-ventilated area out of direct sunlight for about a week, until they feel papery and snap rather than bend.
For alcohol tinctures, you can use either fresh or dried flowers. Fresh flowers actually work well here because the alcohol is strong enough to prevent microbial growth. If using dried flowers, you’ll need roughly half the volume you’d use fresh, since drying concentrates the plant material.
Whole flower heads give the richest extract. The orange and yellow petals hold the highest concentration of carotenoids and flavonoids, but the green base of the flower contains triterpenes and saponins worth capturing. Crumble or coarsely chop the dried flowers to increase surface area and improve extraction.
How to Make a Calendula Oil Infusion
You have two options here: a slow cold infusion that takes weeks, or a faster heat method that finishes in hours.
Cold Infusion (4 to 6 Weeks)
Fill a clean, dry glass jar about two-thirds full with dried calendula flowers. Pour your carrier oil over the flowers until they’re completely submerged with about an inch of oil above them. Seal the jar tightly. Place it in a warm spot that gets indirect sunlight, like a sunny windowsill. Shake the jar once daily for four to six weeks. The oil will gradually turn a deep golden orange as the compounds transfer.
This method preserves heat-sensitive compounds and produces the most vibrant color. The trade-off is patience.
Heat Infusion (4 to 6 Hours)
Place your jar of flowers and oil (prepared the same way as above) into a slow cooker filled with a few inches of water to create a water bath. Set it to the lowest heat setting and let it process for four to six hours. The water bath distributes heat gently and prevents the oil from overheating, which would degrade the active compounds. Check periodically to make sure the water level stays consistent and the oil isn’t bubbling.
A yogurt maker or electric pressure cooker on its yogurt setting produces temperatures around 110 to 115°F, which is too low for calendula. The resinous quality of calendula flowers requires more heat than delicate aromatic herbs, so a slow cooker’s low setting (around 140 to 180°F depending on the model) is a better fit.
How to Make a Calendula Tincture
Pack a clean glass jar loosely with dried calendula flowers, filling it about halfway. If using fresh flowers, fill the jar about three-quarters full. Pour 80-proof or higher vodka over the flowers until they’re fully submerged with at least an inch of liquid above them. Seal tightly with a lid.
Store the jar in a cool, dark place like a cupboard. Shake it once a day. Let it steep for four to six weeks. The alcohol will pull flavonoids, phenolic acids, and other water-soluble and alcohol-soluble compounds from the petals, turning a rich amber color. Longer steeping generally produces a stronger extract, but six weeks is sufficient for most purposes.
Straining and Filtering
Once your infusion or tincture has finished steeping, you need to separate the liquid from the spent plant material. Start by pouring everything through a fine mesh strainer lined with cheesecloth into a clean bowl or jar. Gather the cheesecloth around the flowers and squeeze firmly to press out as much liquid as possible. This step matters more for oil infusions, where every drop of oil you leave behind is wasted product.
For a cleaner final product, strain a second time through a fresh piece of cheesecloth or a coffee filter. This removes fine sediment that can cloud the extract or settle at the bottom of your storage container. Tinctures are generally less prone to sediment than oil infusions, but a second pass still improves clarity.
Storage and Shelf Life
Transfer your finished extract to dark glass bottles, either amber or cobalt blue. Light degrades carotenoids and flavonoids over time, so clear glass sitting on a bathroom shelf will weaken your extract faster than necessary. Keep it in a cool location away from heat sources.
Alcohol tinctures last the longest. Stored properly in a sealed dark bottle, they remain potent for three to five years. The high alcohol content acts as its own preservative.
Oil infusions are more perishable. Expect a shelf life of about 12 months when stored in a dark bottle in a cool place. Commercial calendula extracts stored in original sealed containers can last up to 24 months, but homemade versions lack the same controlled conditions. If your oil smells rancid or off, discard it. Adding a few drops of vitamin E oil (a natural antioxidant) at the time of bottling can help extend the oil’s freshness by a few months.
Safety Considerations
Calendula belongs to the Asteraceae family, which includes ragweed, chamomile, and daisies. Roughly 2% of people with plant allergies react to calendula allergens, and reactions can range from contact skin irritation to, in rare cases, severe allergic responses. If you’re allergic to ragweed or other plants in this family, test your extract on a small patch of skin before using it broadly. Symptoms to watch for include redness, itching, or swelling at the application site.
For topical oil infusions, the risk is low for most people. Calendula has a long history of safe external use for skin irritation and minor wounds. Tinctures taken internally carry slightly more consideration, particularly during pregnancy, as calendula has traditionally been avoided by pregnant women due to its potential effects on uterine activity.