Henna powder that is still sealed should be stored in a cool dry place away from light and out of reach of children. The refrigerator is fine, but not necessary. For long term storage (3 months or more) you can tightly wrap the henna and freeze it.
For henna paste, freezing your henna is the best option to keep it fresh.
Once henna has been opened (both powder and pre-mixed) and exposed to air, it should be stored properly or may be less effective. If you plan to use your henna in a week or so, store it in the refrigerator. A light proof, sealed container is ideal to protect the henna from light and excessive humidity. Keeping it sealed also prevents any essential oils in the henna scenting your food in the fridge!
For longer storage, wrap henna paste or powder tightly and store in the freezer to keep it fresh. The henna could be frozen in individual packs so you only have to thaw as much henna as you need.
Leave the henna out at room temperature to defrost. Or if you need it sooner sit the unopened container in a bowl of warm water for a while, carefully dry it and you’re ready to go.
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