Cannabis is a genus of plants in the Cannabaceae family, and although the number of cannabis species within the genus is debatable, there are three basic species:

  • Cannabis sativa,
  • Cannabis indica,
  • Cannabis ruderalis

Cannabis sativa originates from the equatorial zones around the world and grows up to 4-6 meters high in the heat and light of the tropics. Shorter, large-leafed Cannabis indica varieties have adapted to grow at higher altitudes. Ruderalis is short, fibrous and has a remarkable range of uses from ropes to fabrics to nutritional supplements.

The cannabis leaf is a trademark with its serrated leaves and palm-like pattern. Cannabis is hermaphroditic, meaning that there are both male and female plants. However, purely female or purely male plants are not uncommon. Until flowering, the sexes differ in size and shape. The female plant is shorter and has thicker foliage, the male is larger and sparsely leafed.

Some botanists include C. ruderalis with C. sativa. In addition, all three have been classified as subspecies of a single species, C. sativa. This classification helps to understand the differences within cannabis varieties. In addition, it helps in understanding how and why their medicinal properties vary. Cannabis varieties have been bred to produce varying amounts of THC, the main psychoactive ingredient. Strength of THC is increased by drying the flowers.



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