How to Make Herbal-Infused Oils Using the Alcohol Intermediary Method

When making herbal salves, most people are familiar with two common methods of infusing herbs into oil: the traditional cold infusion that takes several weeks and the quick heat infusion that can be completed in a few hours. While both methods have their place, there's another technique that many experienced herbalists appreciate—the alcohol intermediary method.

This method uses a small amount of high-proof alcohol to lightly moisten dried herbs before adding oil. The alcohol helps break down plant cell walls and makes certain herbal constituents more accessible, allowing the oil to capture a broader range of beneficial compounds during the infusion.

If you're looking to elevate the quality of your homemade salves, this method is well worth trying.

What Is the Alcohol Intermediary Method?

Many medicinal herbs contain both oil-soluble and water-soluble constituents. Traditional oil infusions primarily extract compounds that dissolve readily in oil, while water-soluble compounds are more difficult to capture.

By lightly moistening dried herbs with a small amount of alcohol before adding oil, the alcohol begins extracting some water-soluble constituents and helps rupture plant cell walls. As the herbs sit in the oil, those constituents can become suspended throughout the infusion, creating a more complete herbal oil.

Only a small amount of alcohol is used—just enough to dampen the herbs, not soak them.

Why Use Dried Herbs?

Properly dried herbs are essential for making stable herbal oils.

Fresh herbs contain significant moisture, which can encourage mold growth and shorten the shelf life of your finished infusion.

Starting with premium dried herbs results in cleaner, longer-lasting infused oils.

Supplies You'll Need

• Dried herbs

• High-proof food-grade alcohol (typically 80–190 proof, depending on availability)

• Carrier oil (olive, sunflower, sweet almond, grapeseed, etc.)

• Glass jar with lid

• Measuring spoons

• Cheesecloth or fine mesh strainer

• Double boiler or slow cooker (optional)

Step 1: Measure Your Herbs

Fill a clean glass jar about halfway to three-quarters full with dried herbs.

If using a scale, weigh your herbs so you can accurately determine the amount of alcohol needed.

Step 2: Lightly Moisten the Herbs

A commonly used guideline is to use approximately 1 tablespoon of high-proof alcohol for every ounce (28 grams) of dried herbs.

Drizzle the alcohol evenly over the herbs while stirring until they are evenly dampened. The herbs should feel slightly moist but should not be swimming in liquid.

Seal the jar and allow the herbs to rest for 12 to 24 hours. This resting period allows the alcohol to penetrate the plant material and begin breaking down cell walls.

Step 3: Add the Oil

After the resting period, pour your carrier oil over the herbs until they are completely covered by one to two inches of oil.

Stir gently to release trapped air bubbles.

Seal the jar tightly.

Step 4: Allow the Oil to Infuse

Place the jar in a cool, dark location for 2 to 4 weeks, shaking it gently every day or two.

Some herbalists choose to finish the infusion with gentle heat by placing the jar in a warm water bath for two to four hours. This step is optional but may help complete the extraction.

Avoid overheating the oil. Keeping temperatures around 100–120°F (38–49°C) helps preserve delicate herbal constituents.

Step 5: Strain the Oil

When the infusion is complete, strain the oil through several layers of cheesecloth or a fine mesh filter.

Squeeze the herbs well to recover as much infused oil as possible.

Allow the oil to settle if needed, then pour off the clear oil into clean bottles.

Turning Your Infused Oil Into Salve

Once your herbal oil is finished, making a salve is simple.

A common starting recipe is:

• 1 cup infused herbal oil

• 1 ounce beeswax

Warm the oil gently, stir in the beeswax until completely melted, then pour into tins or jars while still liquid.

Adjust the beeswax to create a softer balm or a firmer salve based on your preference.

Herbs That Work Especially Well

Many herbs respond beautifully to the alcohol intermediary method, including:

• Comfrey

• Calendula

• Plantain

• Yarrow

• Arnica (external use only)

• Chickweed

• Lemon balm

• Lavender

• Chamomile

• St. John's wort

• Cottonwood buds (for topical preparations)

Benefits of the Alcohol Intermediary Method

Many herbalists choose this technique because it may:

• Help rupture plant cell walls for improved extraction

• Support extraction of a broader range of herbal constituents

• Produce richly infused oils

• Work especially well with resinous or tougher herbs

• Create excellent infused oils for salves, balms, and massage oils

While herbal tradition supports this method, scientific research comparing extraction efficiency across different oil infusion techniques is still limited. Results can vary depending on the herb, oil, alcohol strength, and infusion conditions.

Tips for Success

• Always use completely dried herbs.

• Use only enough alcohol to lightly dampen the herbs.

• Keep all herbs fully submerged beneath the oil.

• Store finished oils in dark glass bottles away from heat and direct sunlight.

• Label every batch with the herb, oil, and infusion date.

Final Thoughts

The alcohol intermediary method is a favorite among many experienced herbalists because it combines traditional wisdom with a thoughtful extraction technique. By using just a small amount of alcohol before adding the oil, you can create richly infused herbal oils that are perfect for handcrafted salves and body care products.

Whether you're making a soothing comfrey salve, a nourishing calendula balm, or your own custom herbal blend, taking a little extra care during the infusion process can help you produce a high-quality finished product.

Happy infusing!