Leaving us with 2 main cannabis strains and that is Sativa and Indica. Sativa Sativas and Indicas are very different, like night and day. They are tall, thin plants, with much narrower leaves and grow a lighter green in color.They grow very quickly and can reach heights of 20 feet in a single season.eaving us with 2 main cannabis strains and that is Sativa and Indica. Sativa Sativas and Indicas are very different, like night and day. They are tall, thin plants, with much narrower leaves and grow a lighter green in color. They grow very quickly and can reach heights of 20 feet in a single season.