If by Salvia you mean Salvia Divinorum, then the answer is no. Salvia Divinorum is not used in Chinese medicine, as Salvia does not naturally grow in any region of China. Salvia Divinorum is only to be found in Oaxaca, Mexico.
No, Salvia nemorosa does not contain salvinorins, the active components of Salvia divinorum.
Although some studies have indicated that Salvia divinorum may be effective in treating the symptoms of depression, taking Salvia divinorum (particularly smoking it) should be considered unhealthy, especially because the long term effects of Salvia divinorum usage are not well-known.
Whether or not one can purchase Salvia divinorum at the beach depends largely on what state/country the beach is in. Because S. divinorum is illegal in some states and countries, those beaches would probably not have vendors selling the product. On the other hand, at beaches where S. divinorum is legal and there is a suitable demand, Salvia may be sold by some beach shops.
smoke it
No.
Salvia divinorum does flower, but it is very difficult to start a plant from seed. Usually, plants are cloned from cuttings.
No it is not possible to test for salvia.
Depends on what kind of salvia you're talking about. Only Salvia Divinorum species can get you high. Don't get fooled, there are a lot of varieties of Salvia.
Yes, Salvia divinorum is legal plant in the Lebanon.
Salvia divinorum is the only species in the genus Salvia that contains Salvinorins. Thus, smoking other species of Salvia, including the ornamental Mystic Blue, would not have the same effect.
Salvia Divinorum grows only in Oaxaca, Mexico.