Mullein tea requires little more than dried leaves or flowers steeped in hot water and carefully strained, while mullein oil and tinctures call for longer extraction times and different solvents. The plant, Verbascum thapsus, has been used for centuries to address respiratory and ear complaints, and its preparations are straightforward enough for a home kitchen. The details that matter most are which plant parts to use, how to dry and filter them properly, and where the plant was growing before you picked it.
Which Parts of the Plant to Use
Mullein is a tall, fuzzy biennial that grows wild across roadsides, disturbed fields, and dry slopes throughout much of North America, Europe, and parts of Asia. Every above-ground part has been used in folk medicine at one time or another, but the leaves and flowers are the most common choices for home preparations. The leaves are large, velvety, and covered in fine hairs. The flowers are small, yellow, and clustered along a tall central spike that can reach well over a meter in height.
For tea, both leaves and flowers work. The leaves produce a milder, slightly earthy brew, while the flowers tend to be sweeter and more aromatic. Traditionally, the flowers have been favored for infused oils, especially those intended for ear discomfort. An infusion of the flowers in olive oil has long been used as earache drops, and the plant’s tea has been taken for a range of chest and abdominal complaints including productive cough.1SciELO – Scientific Electronic Library Online (Revista Brasileira de Farmacognosia). Common mullein, pharmacological and chemical aspects The roots have occasional uses in herbalism but are far less common in home preparation and harder to process, so most people stick with leaves and flowers.
Drying Mullein Properly
Fresh mullein can be used in preparations, but drying concentrates the plant’s compounds and makes storage practical. Spread leaves in a single layer on a screen or drying rack in a warm, well-ventilated area out of direct sunlight. Direct sun can degrade some of the plant’s more delicate compounds. Flowers are best dried the same way, though they are smaller and more fragile, so handle them gently to keep them intact.
Depending on humidity, leaves take anywhere from a few days to about a week to dry completely. They should feel papery and crumble easily when you pinch them. Flowers dry faster, usually in two to four days. Once fully dry, store the material in airtight glass jars away from light and heat. Properly dried mullein keeps for about a year before its flavor and potency start to fade noticeably.
Making Mullein Tea
Mullein tea is the simplest preparation. Place one to two teaspoons of dried leaves or flowers (or a mix of both) in a mug, pour just-boiled water over them, and let the mixture steep for ten to fifteen minutes. A longer steep pulls out more of the plant’s compounds but can also make the tea more astringent, so adjust to your taste.
The single most important step is straining. Mullein’s leaves and stems are covered in tiny, hair-like trichomes that can irritate the throat and stomach if swallowed. Pour the tea through a fine-mesh strainer lined with cheesecloth, a paper coffee filter, or a cloth tea bag. A standard kitchen strainer alone is usually not fine enough to catch all the hairs. If the tea still feels scratchy or gritty, strain it a second time. This extra effort is not optional for comfort.
The finished tea has a mild, slightly sweet, grassy flavor. Some people add honey or lemon, which complements the taste nicely. Herbalists who use mullein for respiratory support often recommend drinking it warm, since the steam and warmth can help on their own when you are congested. Two to three cups per day is a common recommendation in traditional use, though there is no rigidly established dose in the scientific literature.
Preparing Mullein-Infused Oil
Mullein flower oil is one of the oldest and most widespread preparations from this plant. The traditional method uses only two ingredients: dried mullein flowers and a carrier oil, most commonly olive oil. Pack a clean, dry glass jar loosely with dried flowers, then pour olive oil over them until the flowers are fully submerged with at least a centimeter of oil above the top layer. Any flowers poking above the oil line can introduce moisture and eventually mold.
Seal the jar and place it in a sunny windowsill for two to three weeks. Some herbalists prefer four to six weeks for a stronger infusion. Shake or swirl the jar gently every day or two to keep the flowers distributed. The oil will gradually take on a golden-yellow hue as it extracts compounds from the flowers. After the infusion period, strain the oil through cheesecloth, squeezing out as much liquid as possible from the spent flowers, then strain again through a finer filter to remove any remaining plant matter.
If you prefer a faster method, you can use gentle heat. Place the flower-filled jar in a small pot of water (a double-boiler setup) and warm it on the lowest heat setting for several hours. The oil should never get hot enough to bubble or smoke. This shortcut can produce a usable infusion in a single afternoon, though many herbalists feel the slow cold-infusion method yields a better product.
Store the finished oil in a dark glass bottle in a cool place. It keeps for about six months to a year, depending on the carrier oil. Olive oil is traditional and stable, but some people use almond oil or jojoba oil instead. If the oil develops an off smell or becomes cloudy, discard it.
Making a Mullein Tincture
A tincture uses alcohol as the solvent instead of water or oil, which extracts a broader range of compounds and produces a preparation with a much longer shelf life. The standard approach is to fill a clean glass jar about halfway with dried mullein leaves, flowers, or both, then pour 80-proof (40% alcohol) vodka over the plant material until it is fully covered. Vodka is the most common choice because it is neutral in flavor and widely available at the right proof.
Seal the jar tightly and store it in a cool, dark place for four to six weeks. Shake it every few days to keep the extraction going. After the infusion period, strain through cheesecloth and then through a fine filter, just as with the tea and oil. The same trichome concern applies here: you do not want to swallow those tiny hairs.
Tinctures are typically taken in small amounts, often a dropperful (about 1 mL) diluted in a small glass of water, up to three times daily. The alcohol base means a properly made tincture can last for years without spoiling. If you want to avoid alcohol, some herbalists make tinctures with food-grade vegetable glycerin instead, though glycerin is a weaker solvent and may extract fewer compounds.
What Mullein Actually Contains
The reason mullein has persisted in herbal traditions for so long comes down to its chemical profile. The plant contains saponins, flavonoids, iridoid and phenylethanoid glycosides, vitamin C, and various minerals.2Revista Brasileira de Farmacognosia. Common mullein, pharmacological and chemical aspects Among these, verbascoside (a phenylethanoid glycoside) has drawn the most research attention. Cell studies have shown that verbascoside reduces the production of certain inflammatory molecules, which aligns with mullein’s long traditional use for soothing irritated airways.3PubMed. Antiinflammatory effects in THP-1 cells treated with verbascoside
The saponins are thought to be partly responsible for mullein’s expectorant reputation. Saponins can reduce the surface tension of mucus, making it easier to cough up, which is one reason the plant has been used for productive coughs and bronchitis.4IntechOpen. Utilization of Medicinal Herbal Plants in the Management of Respiratory Conditions The flavonoids contribute antioxidant activity. Altogether, different extracts of Verbascum thapsus have shown a range of biological activity in lab settings, including antioxidant, antimicrobial, antiviral, and wound-healing properties.5The Natural Products Journal. Extensive Phytochemistry, Comprehensive Traditional Uses, and Critical Pharmacological Profile of the Great Mullein: Verbascum thapsus L
It is worth noting that most of this research involves isolated compounds or crude extracts tested in lab dishes and animal models, not clinical trials of mullein tea or tincture in humans. The gap between “this compound does something interesting in a petri dish” and “this tea will fix your cough” is wide and not yet fully bridged by rigorous human studies. That said, the lab findings are consistent with what traditional users have reported for centuries, which is why researchers continue to investigate.
Antibacterial and Antiviral Findings
One area where mullein’s lab results are particularly interesting is antimicrobial activity. A water-based extract of mullein showed antibacterial effects against several common pathogens, including Staphylococcus aureus and Escherichia coli.6PubMed. Biological activity of common mullein, a medicinal plant The fact that the water extract performed well is relevant because tea is essentially a water extract, so the compounds responsible for antibacterial activity are the same ones you are pulling into your cup.
On the antiviral side, recent research tested Verbascum thapsus extracts against human parainfluenza virus in cell cultures. The results showed a dose-dependent antiviral effect, with the strongest viral inhibition occurring when the extract was applied at the same time the virus was introduced to the cells. This suggests the plant compounds may interfere with early stages of viral entry or replication.7Pharmacological Research – Modern Chinese Medicine. In vitro antiviral potential of H. helix L. and V. thapsus L. on Vero cell adapted human parainfluenza virus (HPIV) With molecular docking insights Again, these are cell-culture findings, not proof that drinking mullein tea will fight off a virus in your body. But they do provide a plausible mechanism behind the traditional use of mullein for respiratory infections.
Mullein Oil for Ear Discomfort
One of mullein’s most specific traditional applications is as ear drops. Mullein flower oil, sometimes combined with garlic, has been a go-to remedy in folk medicine for earaches. A clinical trial involving children with ear pain from acute middle ear infections compared a naturopathic herbal ear drop preparation (which included mullein among other herbs) to a conventional anesthetic drop. Both groups showed significant improvement in ear pain scores over the study period.8PubMed. Efficacy of naturopathic extracts in the management of ear pain associated with acute otitis media
That study used a multi-herb formula, so it is not possible to attribute the effect to mullein alone. Still, it is one of the few actual clinical trials touching on mullein’s traditional uses, and the results were encouraging enough that naturopathic ear drops remain popular. If you plan to use homemade mullein oil in the ear, make sure the oil is well-strained, at room temperature or slightly warmed, and that there is no possibility of a ruptured eardrum. Oil should never be dropped into an ear with a perforation. When in doubt, have a doctor look first.
Where You Harvest Matters More Than You Think
Here is where mullein preparation gets a safety dimension that most herbal guides skip over. Mullein is a proven hyperaccumulator of heavy metals, particularly cadmium. Research on mullein growing across the St. Louis region found that the levels of certain heavy metals in the plants made them unsafe for medicinal use, with some concentrations exceeding established health standards.9ResearchGate. Exploring Heavy Metal Accumulation in Verbascum thapsus (Common Mullein) Across the St. Louis Region Separately, a study of mullein growing on polluted soil found that zinc, lead, chromium, and cadmium in the plants exceeded maximum permissible levels, some by staggering margins.10PubMed. Influence of soil pollution on the morphology of roots and leaves of Verbascum thapsus L.
Mullein also accumulates copper at levels well above the threshold for a hyperaccumulator plant, concentrating it heavily in its shoots.11PubMed. Assessment the copper-induced changes in antioxidant defense mechanisms and copper phytoremediation potential of common mullein (Verbascum thapsus L.) These qualities actually make mullein useful for cleaning contaminated soil, a process called phytoremediation. But they also mean that a mullein plant growing next to a busy highway, near an old mine, beside railroad tracks, in industrial areas, or on land with a history of pesticide use could be carrying a concentrated dose of metals you absolutely do not want to brew into tea or infuse into oil.
One somewhat reassuring detail from the research: the inflorescences (the flower spike) tend to accumulate lower levels of heavy metals compared to the roots, stems, and leaves.10PubMed. Influence of soil pollution on the morphology of roots and leaves of Verbascum thapsus L. This is good news for preparations that rely primarily on flowers, like the traditional ear oil, but it does not eliminate the concern entirely. If you are harvesting wild mullein, choose plants growing in areas well away from roads, industry, and known contamination. Fields, meadows, and undisturbed rural land are better bets. If the soil history of a location is unknown, buying dried mullein from a reputable supplier who tests for contaminants is the safer choice.
Practical Tips for Better Preparations
A few details can make the difference between a preparation you enjoy using and one you pour down the drain:
- Always double-strain: Whether you are making tea, oil, or tincture, those microscopic leaf hairs will find their way into your final product if you use only a single pass through a coarse strainer. Cheesecloth over a fine-mesh strainer, or a paper coffee filter, is the minimum.
- Dry completely before oil infusions: Any residual moisture in the flowers can cause your oil to go rancid or grow mold. If you are uncertain whether your flowers are fully dry, give them an extra day or two. You can also wilt them on a baking sheet in an oven set to its lowest temperature for an hour.
- Label and date everything: Mullein tea stored in jars looks a lot like many other dried herbs. Tinctures and oils are even harder to tell apart after a few months. Write the contents, the date of preparation, and the carrier oil or solvent on the jar.
- Test before committing: If you have never used mullein before, start with a small amount. Allergic reactions to mullein are uncommon but not impossible, especially in people with sensitivities to other plants in the Scrophulariaceae family. Try a small cup of tea and wait a day before making a large batch.
Mullein Across Herbal Traditions
Mullein is not a single-culture remedy. Its use spans European, Middle Eastern, and American folk medicine traditions. In Spain alone, the traditional pharmacopoeia includes ten different Verbascum species used to treat various conditions, catalogued in the country’s official Inventory of Traditional Knowledge related to Biodiversity.12PubMed Central. Searching for Scientific Explanations for the Uses of Spanish Folk Medicine: A Review on the Case of Mullein (Verbascum, Scrophulariaceae) Native American tribes used mullein for coughs and lung complaints. In Appalachian folk medicine, mullein leaf tea was a standard household remedy for congestion. European herbalists dating back centuries recorded its use for everything from hemorrhoids to tuberculosis.
This wide geographic and cultural spread is part of what makes mullein interesting to researchers. When dozens of independent traditions converge on roughly the same uses for a plant, it lends some weight to the idea that something real is going on pharmacologically, even before modern lab studies confirm specific mechanisms. The convergence on respiratory uses is especially strong, and it is why mullein tea remains one of the more popular herbal remedies for coughs and chest congestion today, available in pre-packaged tea bags at most health food stores alongside the loose-leaf versions that home herbalists prefer.
Shelf Life and Storage
How long your preparations last depends almost entirely on the solvent and how you store them. Dried mullein herb keeps for about twelve months in an airtight container away from light and heat. After that, it does not become dangerous, but it loses flavor and likely some of its active compounds. Tea should be consumed the day it is brewed, or refrigerated and drunk within a day or two.
Mullein-infused oil has the shortest shelf life of the three preparations. Olive oil-based infusions generally stay good for six months to a year when stored in a dark glass bottle in a cool pantry. Heat and light accelerate rancidity. If you live somewhere warm, consider refrigerating the oil to extend its usable life. Tinctures are the long-haul option. The alcohol acts as a preservative, and a properly made mullein tincture stored in a dark glass bottle with a tight seal can remain stable for three to five years. Glycerin-based tinctures do not last as long, typically one to two years, because glycerin is a weaker preservative than alcohol.