Salvia divinorum plants grow best in light shade with no more than 3 or 4 hours of direct morning or afternoon sunlight. Avoid direct sunlight during midday. They won’t tolerate a lot of strong direct sunlight. On the other hand, they do not do well in deep shade either. Light shade and filtered sunlight is best.
Salvia Divinorum is a semi-tropical perennial. That means that Salvia Divinorum can grow year after year, but only if Salvia Divinorum is not exposed to freezing temperatures. Salvia Divinorum is a green plant with large leaves and a distinctive thick, hollow, square green stem. Salvia Divinorum can grow several meters (yards) high if conditions are favourable. When Salvia Divinorum grows high enough, the branches will bend, or break, and may root if they come in contact with moist earth. Although Salvia Divinorum can flower under natural lighting conditions, it almost never sets seed that will sprout.
So, the Salvia Divinorum plant is almost always propagated by cuttings. The leaves are oval, weakly notched (serrated) and can be quite large (up to 9 inches in length). They are usually emerald green, but under some conditions, may be yellow-green or even yellow. They are covered with a fine coating of extremely short hairs (trichomes), giving the leaves a satin like velvety appearance in certain lights. Salvia Divinorum plants grow best in partial shade, in well-watered, but well drained, soil. The roots must not be kept constantly soaked, or root-rot will set in and kill the Salvia Divinorum plant.
Salvia Divinorum can be grown indoors in any climate. Salvia Divinorum makes a beautiful house plant.
You can grow Salvia Divinorum outdoors all year round if you live in a humid semi-tropical climate, with well-watered, but well-drained soil, with high humus content. If you live in a colder or drier climate, you can still grow Salvia Divinorum outdoors, weather permitting. But you may have to do it with some care, making sure the Salvia plants are protected from frost, watered frequently, and misted when humidity is low. Salvia will not live through freezing or drought. Salvia Divinorum can be grown outdoors in pots which can be brought indoors when it is cold (below 40 degrees Fahrenheit). That way Salvia Divinorum can be grown outdoors in summer and indoors in winter.
Salvia Divinorum soil and watering
Salvia will tell you when it is getting too dry: its leaves will droop. Be sure to water your Salvia Divinorum plant at the first sign of mild drooping-do not let the Salvia Divinorum plant become limp. The soil should drain well but should be kept moist.
Growing Salvia Divinorum in pots
If planting Salvia Divinorum in pots, make sure the pot is large enough to allow the Salvia Divinorum plant to grow well. Although your available space will limit possible pot size, use the biggest pot that is practical. It must have drainage holes. Placing gravel (or broken up pieces of crockery) in the bottom of the pot will help promote drainage and thus discourage root rot. Most commercial potting soil will work well. Adding vermiculite or perlite to the potting soil is helpful but not essential.
Fertilizing Salvia Divinorum plants
Salvia will need fertilizer. Any good general-purpose fertilizer will work. Fish emulsion is a good organic fertilizer choice, but because it has a very unpleasant odor, it is suitable only for outdoor use. Satisfactory results can be achieved with chemical fertilizer products.
Tips for growing Salvia Divinorum
If growing indoors, take the Salvia Divinorum plants outdoors when it is warm enough and let rain fall on them. This will prevent mineral salts from building up in the soil and killing your Salvia Divinorum plant Salvia Divinorum can do well in a variety of different lighting conditions. It does best with a few hours of partial sunlight a day. It can do well when grown indoors near a window. The Salvia Divinorum plants can handle more sun if kept well watered and misted frequently. Salvia Divinorum can also handle moderately deep shade. When changing the lighting conditions or the humidity conditions your Salvia Divinorum plants are exposed to, do so gradually. Given enough time, Salvia is very adaptable, but it may take weeks to get used to a new environment.
Protecting your Salvia Divinorum plants
Many pests can attack Salvia. Whitefly is a big problem for greenhouse grown Salvia Divinorum plants. Aphids, slugs, caterpillars, thrips, spider mites, and scale insects can also damage your Salvia Divinorum plants. Root-rot and stem-rot can be problems. Fungal spots can appear on leaves. It is not known which plant viruses attack Salvia Divinorum, but probably some do, as many attack other sages. Aphids and scale insects can be removed with a cotton swab dipped in isopropyl (rubbing) alcohol. Slug damage can be reduced by growing Salvia in pots on a raised deck or palette. Some may still get by and attack your Salvia Divinorum plants. Keep an eye out for these slimy pests. One slug can eat an awful lot of Salvia! Beer can be used to attract and drown slugs. Set a saucer of beer in a slight depression in the ground; the surface of the saucer should be flush with the soil, so slugs can get in, get drunk, and drown. Spider mites can be controlled by dissolving Castile soap in water and spraying the leaves, including the underside. Repeat at two-week intervals for three applications. Caution: there have been some reports of soap damaging leaves, so don’t use too much. Your garden hose is your best friend in fighting most outdoor pests. Spray the leaves hard enough to blow the pests away, but not hard enough to damage the leaves. Don’t forget to spray the underside of the leaves too. A fine mist nozzle works best for this.
Propagating Salvia Divinorum plants
Salvia Divinorum is usually propagated by cuttings, not by seed. Cuttings may be rooted either in water or directly in soil. Here’s how:
Rooting Salvia Divinorum in water
Cut off a branch (4-8 inches long) bearing some leaves. Cut off the leaves that are attached to the lowest node on your cutting then immediately place it in about one and a half inches of water in a small water glass. Only one cutting is to be put in each glass, so if rot develops in one cutting it cannot spread to another. It is best if the cutting is cut back to just below a node, since nodes are the places from which new roots are most likely to develop. While it is not necessary to make the cut here, doing so has the advantage that there will be no stem material dangling in the water below the node. This is important as the cut stem end is more likely to start to rot than is a node. Make sure the cutting is made with clean shears, or a knife, so the cut stem does not get attacked by germs and fungi that could cause stem rot. Place it where it will get some filtered sunlight. Change the water daily. It may be a good idea to use cooled boiled water. If your water is chlorinated, boiling will drive off chlorine. Non chlorinated water may be contaminated with plant disease germs, but boiling should kill these. Rooting in water is successful about 75% of the time (the rest of the time stem rot occurs and kills the cutting). In two weeks, roots will start to develop. When they are about 1/2-1 inch long, transplant to potting soil in a well-drained pot. Cover with a clear glass jar or clear plastic bag to serve as a humidity tent until the Salvia Divinorum plant establishes its roots in the soil and appears vigorous (usually 1-2 weeks). Then gradually wean the Salvia Divinorum plant from dependence on the humidity tent.
Rooting Salvia Divinorum in soil
Salvia can be rooted directly in soil. Materials needed:
- Potting soil.
- Two disposable plastic cups.
- Some Rootone® powder (this is a rooting hormone mixture that also contains a fungicide) it is available at any nursery.
- A 1-gallon thin, transparent polyethylene food storage bag.
- A rubber band.
Punch some small holes in one of the cups for drainage. Fill the cup 2/3 the way up with potting soil. Using a pencil or a finger make a hole in the soil about 2 inches deep. The soil is now ready for your cutting. You must now prepare the cutting. With clean shears, cut off a length of stem from a healthy Salvia Divinorum plant. Leave a few leaves (small ones) on top. Harvest the larger leaves from the cut-off stem. Immediately after cutting the stem, place it in clean water. Cut it back to just below a node, as roots will develop from the node. Keep the cut surface wet. Place the cut surface, and the stem for about 1 inch above the cut, into the rooting powder. Shake off the excess. Rooting powder is somewhat toxic, so wash your hands after handling it. Place the powder coated cutting in the hole in the soil. Gently push the soil around the cutting, holding it in place while filling in the hole. Water the planted cutting until some water runs out the drainage holes. Place the cup with the Salvia Divinorum plant in it into the second plastic cup (which is there to catch any runoff water). You may want to put a small piece of wood or plastic in the bottom of the outer cup to act as a spacer. This allows enough space for excess water to drain. Place a 1-gallon clear plastic bag over the rooted cutting, using a rubber band to hold it in place. The rubber band should be outside the bag and the bag outside both cups. The Rubber band holds the bag against the cups. As the plastic bag acts to conserve moisture, frequent watering is not required. After several weeks you can transplant the now rooted Salvia Divinorum plant to a larger pot.