PROCESSING SALVIA DIVINORUM PLANT MATERIAL

Dried Salvia Divinorum leaves should be stored in sealed containers away from light. Stored this way, the leaves will retain their potency for many, many years, perhaps indefinitely (nobody knows just how long).
If you are growing your own, you will probably want to dry leaves for future use. There are several ways to do this.

Nature's Bounty

Wait until the leaves die or are shed. Gather them. Place them on a plate in a room with low humidity. Turn often. Wait until they are dry, then store. It is not known if naturally shed leaves are stronger or weaker than picked leaves.

Advantage: you won't be depriving your Salvia Divinorum plants of leaves it needs.
Disadvantage: you will have to wait until the Salvia Divinorum plant is ready to make a donation to your cause. Leaves may not be in prime condition.

Salvia Tobacco

Take big, freshly picked leaves and place one atop another (like stacking sheets of paper). Then cut through the pile, making 1/2 cm. (1/4 inch) strips. Pile these on a plate into a heap. Turn them twice daily until they are dry but not crispy.

Advantage: The resulting 'tobacco' is said to give a smoother smoke than thoroughly dried leaves.
Disadvantage: It is possible that this slow partial drying results in weaker leaves that may not keep as long as thoroughly dried (crispy) leaves.

Food Dehydrator

Dry in a food dehydrator. These are available where small kitchen appliances are sold. Drying is very fast and thorough. Dry until the leaves, including the leaf stems, are crispy. Touch the leaves with your fingers to see if they are thoroughly dried. If they are, the leaf stems should snap if pressure is applied to it.

Advantages: speed, thorough drying, and convenience.
Disadvantage: cost of buying a dehydrator.

Oven Dried Salvia

Place on an oven proof dish. Oven dry in an oven set at no more than 200 degrees F.

Advantage: speed, thorough drying, and convenience.
Disadvantages: Somewhat less convenient than using a food dehydrator. It may be hard to keep oven temperature at an optimal range.

Calcium Chloride (CaCl2) Drying

Calcium chloride is available from chemical supply houses, or as "Damp-Rid" refills, from most hardware stores. Place a sufficient amount of calcium chloride in the bottom of a polyethylene container. Place a piece of aluminium foil atop the CaCl2, and place the leaves to be dried on top of foil. Curling up the edges of the foil, should prevent the leaves from touching the CaCl2. Then seal the container. The leaves should be dry in about two days.

Advantage: very thorough drying.
Disadvantages: less convenient than other methods. Slow.

However you dry the leaves, place them in a sealed jar away from light. A clean glass canning jar works very well (1-quart Mason jar). Storing the jar inside a kitchen cabinet or medicine chest will keep it away from light. Stored this way, leaves will retain their potency for many, many years.