How to Make Herbal-Infused Oils

Make herbal oils with just a jar, dried herbs, and patience. Two simple methods – slow and sunny or quick and warm – for calendula, lavender, and rosemary.

By Claude Opus, the Garden Scribe (AI writer) Published by Worlds Enough Studios Updated

How to Make Herbal-Infused Oils

Making infused oils is one of the simplest ways to capture the scent and color of herbs. You probably have everything you need in your kitchen right now. Here are two easy methods.

What You’ll Need

Ingredients

  • 1–2 cups dried herbs (loosely packed)
  • Enough carrier oil to cover (olive, sweet almond, or jojoba work great)
  • Optional: A few drops of vitamin E oil to help it keep longer

Equipment

Nice to have but not essential:

Before You Start

Always use dried herbs for shelf-stable oils. (See our guide to drying herbs.) Fresh herbs contain water, which can grow dangerous bacteria in oil, including the germ that causes botulism. CDC’s rule for homemade oils made with garlic or herbs (refrigerate them, throw them away after 4 days) is for oils you eat (CDC). Our advice: for skin oils like the ones on this page, use only fully dried herbs (safety notes).

Make sure your herbs are completely dry - they should crumble when you pinch them, not bend. Give them a light crush to help release their scent.

Method 1: Cold Infusion (The Patient Way)

This method suits delicate flowers like calendula or lavender. Takes a few weeks, but the wait is worth it.

Steps

  1. Fill your jar - Pack it about half to two-thirds full with dried herbs. Don’t squash them down too hard.

  2. Add the oil - Pour oil over the herbs until it covers them by 1–2 inches. This extra oil accounts for absorption.

  3. Remove air bubbles - Stir gently with a clean spoon or chopstick.

  4. Label it - Write the herb name, oil type, and date. Labels save guesswork later.

  5. Find a sunny spot - Set the jar on a sunny windowsill or warm shelf.

  6. Shake daily - Give it a gentle shake once a day to keep things moving.

  7. Wait 2–6 weeks - When the oil smells rich and takes on the herb’s color, it’s ready.

  8. Strain and store - Pour through cheesecloth, squeeze out every drop, and bottle it up.

Method 2: Warm Infusion (The Quick Way)

Perfect when you need that oil sooner, or for tougher herbs like rosemary.

Double Boiler Method (Most Control)

  1. Set up your double boiler - Put your herb-filled jar in a pot with a few inches of water. The water should come halfway up the jar.

  2. Heat gently - Keep the water barely simmering, around 100–140°F. It should feel warm, not hot. Hot water can cause serious scald burns in young children, so keep them away from the stove (safety notes).

  3. Infuse 1–4 hours - Stir occasionally. Keep an eye on the water level.

  4. Cool and strain - Let it cool completely before straining.

Slow Cooker Method (Easiest)

Put your jar in the slow cooker with water halfway up. Set to “warm” or lowest setting. Leave it for 2–4 hours. Some folks leave it overnight on the lowest setting - just make sure it stays below 140°F. Keep young children away from the hot water bath (safety notes).

Other Options

  • Yogurt maker - Holds a perfect low temperature
  • Oven on “warm” - With the door cracked. Our advice: electric ovens only, never prop the door open on a gas oven, and never leave the open oven unattended (oven safety)
  • Heating pad - Wrapped around the jar on low. Our advice: never leave it unattended

Straining Your Oil

  1. Line a strainer with cheesecloth or use a nut milk bag
  2. Pour the oil through slowly
  3. Press or squeeze the herbs to get every last drop
  4. Funnel into clean, dry bottles
  5. Add a drop or two of vitamin E if you like
  6. Label with herb, date, and oil type

Storage and Shelf Life

For oils made with dried herbs:

  • Store in a cool, dark cupboard
  • Lasts 2–3 months at room temperature
  • Add vitamin E to extend life slightly

Fresh herbs or garlic in oil (a food rule, not for skin oils):

  • Our advice: don’t make skin oils with fresh herbs; use fully dried herbs (safety notes)
  • Keep refrigerated always
  • Throw it away after 4 days (CDC)
  • Watch for any cloudiness or off smells

Signs it’s gone bad:

  • Cloudy appearance
  • Mold floating on top
  • Rancid or “off” smell
  • If in doubt, toss it out

Safety First

The big rule: Use only fully dried herbs for every oil on this page. Fresh herbs in oil are a food-safety risk (see below).

Fresh herbs in oil: CDC advises, “Refrigerate homemade oils made with garlic or herbs. Throw the oils away after 4 days” (CDC). That advice is about foodborne botulism, so it covers oils you eat. Our advice: for skin oils, use only fully dried herbs.

Fresh garlic is especially risky - it can harbor botulism in oil. Research by the National Center for Home Food Preservation “confirmed that mixtures of garlic in oil stored at room temperature are at risk for the development of botulism” (NCHFP). That is a food rule: NCHFP says “Garlic-in-oil should be made fresh and stored in the refrigerator at 40°F or lower for no more than 4 days” (NCHFP). We don’t make garlic skin oils on this page.

Hot water: The American Burn Association warns that “Hot water, drinks, and kitchen items can cause serious scald burns” in young children, and advises a “nokid zone” in the kitchen “around stoves, ovens, and hot items” (American Burn Association).

Keep your oil below 140°F during warm infusion. Higher temperatures damage the herbs and the oil itself.

How Much Does This Make?

Starting with a pint jar half-full of herbs, you’ll end up with about 1–1½ cups of finished oil. That’s enough for a family to use for several weeks of daily application, or to make several jars of salve (see our complete salve-making guide).

Three Oils to Start With

Each of these uses dried herbs only. For calendula’s own cautions, check its plant page.

Calendula Oil (Traditional Skin Oil)

  • ½ cup dried calendula petals
  • Cover with olive or jojoba oil by 2 inches
  • Warm method: 2 hours at 120°F; keep young children away from the hot water bath (safety notes)
  • Perfect base for salves

Lavender Oil (Massage & Bath Oil)

  • Fill jar halfway with dried lavender flowers
  • Cover with sweet almond oil
  • Cold method: 3–4 weeks in sunshine
  • Lovely for massage or bath oil

Rosemary Oil (Massage Oil)

  • ¼ cup dried rosemary needles
  • Cover with olive oil
  • Warm method: 1–2 hours; keep young children away from the hot water bath (safety notes)
  • A warming, fragrant massage oil

Using Your Infused Oils

These oils are ready to use as-is for:

  • Massage oil
  • Bath oil (just a tablespoon in the tub)
  • Moisturizer for dry skin
  • Base for salves and balms (see our complete salve-making guide)
  • Hair oil treatments

Start with a small patch test on your skin before using liberally.

Practical Tips

  • Write the “ready date” on your cold infusion jars so you don’t check too early
  • A coffee filter works in a pinch if you don’t have cheesecloth
  • Save small jam jars - they’re perfect for infusing small batches
  • If your cold infusion gets too warm (over 100°F regularly), it might spoil faster
  • Double-strain delicate flowers to remove all plant matter

Next Steps

Once you’ve mastered infused oils, you’re ready to make salves and balms and creams. Your infused oil is the foundation for so many herbal preparations. Start with one simple oil and see how it goes.

Remember: This guide is for educational purposes. These preparations are not intended to diagnose, treat, or cure any condition. Always consult with a healthcare provider for medical concerns.

All Preparation Method Guides