How to Store Essential Oils to Keep Them Fresh

Essential oils are natural and delicate. Light, heat, air and time slowly change their aroma, so a little care in storage keeps them smelling the way they should for longer. This guide covers the four things that age an oil, how long oils keep, and how to look after a filled diffuser cartridge.

Why Storage Matters

An oil that has oxidized smells flat, sharp or simply "off" next to a fresh bottle. Good storage protects the aroma you paid for.

What are the four enemies of fresh oil?

• Light: keep oils in their dark glass bottles and out of direct sunlight.
• Heat: store them somewhere cool and dry, away from radiators, stoves, open flame and sunny windowsills. A closed car on a hot day is a bad place for both oils and the diffuser.
• Air: close caps tightly to slow oxidation, and avoid decanting into part-empty containers.
• Time: even well-stored oil changes eventually, so use opened bottles within a reasonable time.

How Long Do Oils Keep?

Zhithera's essential oils and fragrance oils have a shelf life of three years unopened, stored sealed, away from light, in a cool, dry place. Once a bottle is opened, or the oil is poured into a cartridge, it is best used up fairly soon. Citrus oils such as lemon, sweet orange, bergamot and grapefruit oxidize faster than most, so open those when you plan to use them. If an oil smells noticeably different from when you opened it, it is past its best.

How do you look after a filled cartridge?

A Zhithera cartridge holds 6.5 ml and closes with a silicone cap, which limits the oil's contact with air between sessions. Keep the cap on when the cartridge is out of the diffuser, store it upright somewhere cool and dark, and stick to one oil per cartridge, since mixing scents muddies them. The empty cartridge itself does not expire, but it is a consumable part: replacing it about every five refills keeps the mist at its best. Keeping a spare cartridge on hand makes it easy to switch scents without emptying one out.

Why do storage and diffuser care go together?

Fresh oil and a clean mesh are the two halves of a good-smelling diffuser. Oils thinned with carrier oils can clog the mesh, so stick to oils made for diffusion (see pure oils vs diluted blends), and give the mesh a gentle wipe now and then (how to clean and maintain your diffuser).

Keep Scents True With Zhithera

Store bottles sealed and out of the light, keep filled cartridges capped, and use opened oils within a sensible time. Those few habits keep each scent close to how it smelled the day you opened it.

Frequently Asked Questions

How long does an unopened bottle of Zhithera oil last?

Three years, if it stays sealed, out of the light and in a cool, dry place.

Should I keep essential oils in the fridge?

There's no need. A cool, dark cupboard out of reach of children and pets works well.

Can I leave oil in the cartridge between uses?

Yes, with the cap on. Just use it up within a reasonable time, especially citrus oils.

Essential oils are aromatic products for diffusion only. Do not apply them to skin or swallow them. They are not intended to diagnose, treat, cure or prevent any condition.