Rama tulsi, or green leaf tulsi, is more widespread and can be found in parts of China, Nepal, Southern India and South America. It's used to promote healthy digestion and has a milder taste than other tulsis but a stronger aroma when its leaves are crushed.
Krishna tulsi, or purple-leaf tulsi, grows in many regions around India, but this dark purple variety is harder to find than the green-leafed variety. It's especially useful for healing respiratory infections, ear infections and skin problems. It grows slower than other tulsi varieties, which may contribute to its spicy, peppery flavor and aroma. Purple-leaf tulsi is also less bitter and astringent than other tulsis. In ayurvedic medicine, Krishna tulsi is used for clearing toxins and mental stress
Vana tulsi, or wild forest tulsi, is the hardest tulsi to grow and found growing wild around the foothills of the Himalayas, in the plains of India and some parts of Africa. It's the most flavorful of all tulsis with light green upper leaves and dark green lower leaves.
Each variety of tulsi shares the same basic health benefits and helps the body adapt to stressful conditions and restore physiological functions. Free radicals are destroyed by tulsi's plethora of antioxidants that strengthen the immune system and slow the aging process. Tulsi, especially the green leaf variety, stimulates digestion and relieves flatulence. Skin problems such as eczema, psoriasis and rashes are soothed by tulsi, especially the purple-leaf variety.