The plant used in herbal preparations is nearly always Calendula officinalis, often called the Pot Marigold. The common name marigold refers to a diverse group of flowering plants, but only one species is traditionally recognized for medicinal use. This bright, sun-like flower has been cultivated for centuries across southern Europe, the Middle East, and India, where it was integrated into traditional healing systems.
Identifying the Medicinal Marigold
Accurate identification is important because the medicinal Calendula officinalis is frequently confused with ornamental species from the genus Tagetes, such as African or French Marigolds. Calendula officinalis is a herbaceous annual or short-lived perennial that typically grows to a height of about 12 to 24 inches. The leaves are oblong-lanceolate, somewhat hairy, and the whole plant often feels sticky due to protective resins.
The flower heads of Calendula are yellow or deep orange. The most distinctive identifier is the shape of its seeds, which are brown, curved, and resemble small, ridged crescent moons. Unlike Calendula, most Tagetes species are not consumed and lack the same therapeutic properties. Herbalists often prefer cultivars bred for high resin content, as these resins contain many of the beneficial compounds.
Primary Therapeutic Applications
The therapeutic actions of the Pot Marigold are attributed to its chemical profile, which includes triterpenoid esters, flavonoids, and carotenoids. These compounds work synergistically to provide anti-inflammatory, antimicrobial, and vulnerary properties. Triterpenoids modulate inflammatory pathways, reducing swelling and redness when applied topically.
Calendula is widely used for promoting the repair of damaged skin tissue and is a remedy for minor cuts, scrapes, and burns. This vulnerary effect encourages the formation of new tissue and supports the structural integrity of the skin. Its antimicrobial activity makes it useful in preventing infection in minor wounds and soothing skin conditions like eczema and dermatitis. Furthermore, when taken internally as an infusion, its anti-inflammatory effects can help soothe inflamed mucous membranes, such as those associated with sore throats or mild gastrointestinal irritation.
Practical Preparation Methods
Infused Oil and Salve Preparation
One common application is Calendula-infused oil, which serves as the base for salves and ointments. To prepare the oil, fully dried flower heads, including the sticky green base, are packed loosely into a clean glass jar, filling it about two-thirds of the way. A carrier oil, such as olive, sunflower, or jojoba, is then poured over the flowers until they are completely submerged, covering the plant material by at least one inch.
The sealed jar is typically allowed to infuse for four to six weeks in a warm, dark place, shaken gently every few days to aid extraction. Once the infusion period is complete, the oil is strained through a cheesecloth or fine-mesh sieve, squeezing the plant material to extract all the beneficial compounds. To transform this infused oil into a salve, the oil is gently heated with melted beeswax—a standard ratio is one ounce of beeswax for every four ounces of oil—and then poured into small tins to cool and solidify.
Tincture (Liquid Extract)
For a liquid extract, a tincture can be prepared using alcohol, which is an effective solvent for many of the herb’s active constituents. Fresh or dried flowers are placed in a jar and covered with a high-proof alcohol, such as a 40% to 50% solution (80 to 100 proof vodka). The alcohol content is crucial for extracting both water-soluble and alcohol-soluble compounds, creating a potent preparation that is shelf-stable. After infusing for six to eight weeks in a dark location, the liquid is strained and stored in a dropper bottle for internal or external use.
Water Infusion (Tea)
A simple water infusion, or tea, is primarily used for internal applications like soothing the digestive tract or as a gargle for mucosal inflammation. To make this, one to two teaspoons of dried petals are placed in a cup and covered with eight ounces of boiling water. The infusion should be covered and allowed to steep for approximately ten to fifteen minutes before straining the flowers. This method extracts the water-soluble components, providing a mild preparation for internal use.
Safety Considerations and Sourcing
Before using Calendula for medicine, it is important to confirm that the flowers have been grown without the use of pesticides or chemical fertilizers. Sourcing from a reputable organic supplier or growing the plant yourself ensures the material is clean and potent. When harvesting, the entire flower head should be picked and then thoroughly dried in a warm, well-ventilated area to prevent mold formation before any oil or salve preparation.
Individuals with a known allergy to the Asteraceae family, which includes plants like ragweed, chamomile, and daisies, should use Calendula with caution, as it may cause an allergic reaction. Internal use is discouraged during pregnancy due to the historical association with potential uterine stimulation. Calendula may also interact with sedative medications, potentially increasing drowsiness, so it should be used carefully by anyone taking central nervous system depressants.