Salvia divinorum  is a member of the mint family (Labiatae), along with such familiar herbs as oregano and basil. There are dozens of Salvia  species, but Salvia divinorum  is the only one known to contain the diterpenes salvinorin A (at 96%) and salvinorin B (at 4%).

The plant has hollow, square stems with winged edges. It has opposed sets of ovate leaves that are finely dentate along the edges and grow to 8" in length. The stems are not very sturdy, but with support, the plant can grow to 8'  tall. Filtered sunlight is best, and the plant likes plenty of water and humidity. It rarely sets seed, and when it does the seeds are usually not viable. In the wild, the plant propagates by falling over, and sending out roots where it touches the ground. In a high humidity environment, it is not uncommon to see roots forming on the stem even before the plant has fallen over. In cultivation, cuttings can be taken and this is very easy to do. Using  scissors, cut off a branch tip that has 4 to 6 sets of leaves on it and about 4" of stalk below that. Place the cutting in water so most of the bare stalk is covered; tap water is fine and you don't need to add any nutrients. The cutting may wilt for a day or two, but should be fine after that. Mist the cutting frequently or keep it in a high humidity environment to ease the shock of being cut. When taking cuttings in summer, wait until the evening when cooler temperatures prevent excessive wilting.

In about one week, nodes appear on the stalk where the roots will emerge. In another week, roots will grow out to a length of 1/4 to 3/4" long - this is the time to transplant into soil. Keeping the cutting in water beyond this point will deprive it of nutrients, and longer roots are more susceptible to damage during transplanting.

Transplant into a 4"-6" pot using commercial potting soil or formulate your own. I make a mixture of 1 part compost, 1 part peat moss, 1 part sandy loam and 1/2 part perlite. Salvia divinorum likes a friable soil rich in humus and with good drainage, avoid heavy soils with clay in them. The plant likes a lot of root space; repot often for maximum growth. When you see growth start to slow down, or the plant starting to look ragged, it's time to repot.

The ideal temperature range is in the 60s, but my plants have survived hot spells of 100° and night time temps as low as 35°. In hot weather, make sure the plants have enough shade and plenty of water with frequent misting. In the summer when my plants are outside on my deck, I keep them under 60% shade cloth. I have misters that come on six times a day for one minute, which is long enough to wet all the foliage. The misters are controlled by an electronic timer that screws onto my outside faucet.

My plants can put on 4'-5' of growth during the 6 months they are outside. I have heard that the Salvinorin content is higher in the summer, but this is anecdotal information.

In the fall, growth slows as temperature and light levels decrease. If the temperature falls below freezing, the plant will immediately turn black and die. If the root ball has not frozen, the plant can grow back - often quite prolifically because it has a large root system supporting the new growth. I know it's time to bring my plants inside when the leaves start to blush red from the cold nights - this disappears in a few weeks after being indoors.

Plants will flower in the fall when day length falls to about 10-12 hours of light a day. If you are bringing your plants inside under artificial light, you can abort flowering by increasing the light to 14-16 hours a day. The plants will then go back to vegetative growth and put their energy into leaf production. I enjoy the flowers, so I keep my lights on for only 12 hours a day and let the plants go through their cycle. Each plant sends up a spike that can grow to be a foot in length, filled with many small blue and white flowers. The flowers have a very delicate, spicy scent. Each flower spike will last about a month, but if you have many plants all in different phases of flowering, the whole process will last 2-3 months. I know people who have grown Salvia divinorum for years and it has never flowered for them, even though the plants go through a period of shortened day length. The plants tend to get leggy during flowering, and lose some of their lower leaves, and in general look a little ragged. Once flowering is over, I start increasing the light cycle and the plants return to vegetative growth. Light can be increased up to 18 hours a day for maximum growth, beyond this can be detrimental to the plants.

I am not a big fan of the high priced fluorescent grow lights marketed under names such as Vita Lite, Agro Lite and Grolux. One of these 4' bulbs costs about $15 - you could buy 5-6 standard fluorescent bulbs for this price and they are almost as good. Compared to sunlight, fluorescent bulbs emit light predominantly in the blue spectrum which encourage leaf and stem growth. These bulbs are low in red wavelength light which promotes flower development. Unlike Cannabis where the goal is flower production, the aim with Salvia divinorum  is leaf production, so fluorescent lights are fine. Of course natural sunlight is best, but unless you have a greenhouse or a sunny location indoors, fluorescent bulbs will maintain your plants through the winter until you can get them back outside in the spring.

High Pressure Sodium (HPS) or Metal Halide (MH) lights can also be used. They come in 400w and 1000w sizes, and unless you have a large area to cover, the 400w is plenty. A 400w MH system costs about $200 and puts out as many lumens as 20 fluorescent bulbs. This fixture would provide enough light for an 8'x8' growing space. You need to be sure to keep the light 2' above the tops of the plants; if the leaves start to blush red, the light is too close. Leaves will lighten in color when exposed to high light levels; this is fine and does not effect potency. Using one of these lights will require more humidity as the extra heat they give off will dry out the leaves quicker. HPS lights are higher in the red spectrum and emit a golden light, MH are a more balanced light and would be better for use with Salvia divinorum.
 

The main thing you hear about Salvia divinorum is how much humidity they need,  but this is not true. Yes, the plants enjoy high humidity, and will achieve optimum growth in high humidity, but they can grow just fine in much less humid conditions. The trick is to slowly acclimate the plant to a lower humidity environment over the course of several weeks. If you have ordered a cutting by mail, chances are good it came from a high humidity environment in a greenhouse. Give it high humidity initially by misting it often or placing it in a tent with a humidifier, but slowly reduce the humidity over the course of the next month and the plant will do just fine, and with much less hassle for you. In the winter when my plants are indoors, I cover the walls with plastic sheeting and spray the plants 3 times a day with a pump-style tank sprayer. This takes less than 5 minutes every time I spray them and I never have a problem with leaf edges turning brown, which is the typical sign that the humidity is too low.

If you are going to grow your plants in a high humidity environment, don't make the mistake of thinking that you don't need to water them much - they will still require regular watering even with humidity levels in the 90% range. I do not like using tightly sealed tents or other grow chambers, these do not allow for a healthy flow of air and such stagnant conditions encourage the growth of molds and bacteria.

The most common pests of Salvia divinorum are whiteflies and aphids. They both live on the underside of the leaves, preferring the new growth on the top half of the plant. Aphids will also cluster on the stems. Whiteflies are small insects with bright white wings, their pupa are light green and look like small grains of rice. All stages suck on plant juices, and heavily infested plants will yellow and grow poorly. If the infestation is left unchecked, the plants can be killed from a black sooty mold that grows on the honeydew that the whiteflies and aphids produce.

I have had good results combating whitefly (and to a lesser degree aphids) simply spraying the underside of the leaves with a solution of 1 tsp. liquid castile soap (such as Dr. Bronner's unscented) to 1 qt. of water. The soap breaks down the insects' protective coating and they drown. The plants can be rinsed off the following day with clean water. You will want to repeat this procedure once a week for a couple of weeks to kill any pupa that survived the initial spraying and have turned into adults.

Aphids are a little more resistant to a simple castile soap spray, so I recommend using insecticidal soap on them, such as Safer brand. These soaps contain salts of fatty acids and are quite safe to use, even within days of harvest. The directions say the soap can be left on, but I wash the leaves off the following day after application just to be safe.

There are some biological controls that work wonderfully. The parasitic wasp Encarsiaformosa is very effective against whiteflies. These tiny wasps are barely visible to the eye, they lay their eggs inside developing whitefly pupa, so one of their young hatches out instead of the whitefly. For aphids, try ladybugs or Aphidoletesaphidimyza.

I fertilize my plants about once a month with fish emulsion when they are outdoors in the summer. In the winter I use Stern's Miracid (S. divinorum likes acidic soil.) Feeding a lot of nitrogen to your plants will attract more problem insects to them, so cut back on fertilizing as part of the strategy to bring pests under control.

For all practical purposes, the lifespan of a Salvia divinorum plant is about 5-6 years. The plants get woody as they age, growth slows and they become more brittle and start to fall apart. If they have been staked and prevented from falling over and rerooting, then it is time to take some cuttings and start again. Cuttings from an old plant will show the same vigor as cuttings from a younger plant.

Salvia divinorum leaves should be dried in a food dehydrator on a medium high setting (130 - 140 degrees). At this temperature, drying will take between 1 - 2 hours depending on the size of the leaves. I remove the mid ribs on the large leaves and they never take more than 1 hour to dry. Drying at lower temperatures causes the leaves to lose their green color and turn brown. Once dry, I push the leaves through a sieve to powder them, then pack the powder tightly into glass vials and store in the freezer - potency will be retained for many years this way. Fresh leaves can be stored in the refrigerator for a few days before losing potency, keep them in a plastic bag with a damp paper towel. Freezing fresh leaves does not work, when thawed they turn into a slimy mess. Leaves can be juiced using a wheat grass juicer and then frozen for long term storage - when thawed, the juice is held in the mouth as is done with the fresh leaves. Dried leaves can be reconstituted by soaking in a small amount of water and then chewed.

It is my hope that many people will grow Salvia divinorum; it is one of the rarest of all plant entheogens. It was almost driven into extinction once, let's preserve this species so future generations can learn from this valuable plant ally.