Basil is known to be an annual herb, but some varieties like African Blue and Thai are termed perennial basil because they keep producing new leaves year after year. Both species are raised in tropical areas where the climate  is warm and humid.

Warm, tropical zones can enjoy fresh perennial basil like African Blue and Thai all year round while areas with colder climates present some challenges when it comes to raising perennial basil, but it is not impossibile if you keep it sheltered throughout the winter.

African Blue Basil does not propagate from seed. This hybrid cross produces sterile seeds but it's easy enough to propagate this type of perennial basil from cuttings.
Simply snip off some tips, no more than 5cm long.  It is important to strip away most of the leaves leaving only the top 2 or 3.  Once the cut ends have been dipped into some rooting hormone these cuttings are simply pushed into some good quality potting mix in a container.  I prefer to dip my basil cuttings in honey: it is not a root promoting agent but it is a fungicide.

African Blue is a great landscape plant and a must have in any herb garden for its color and fragrance.  It produces attractive purple blushed flower spikes and makes an eye-catching display.  You can also cut some African Blue basil for herb bouquets and for garnish at the table.

Another variety of perennial basil is Thai basil, also known as Thai holy basil. It is an important ingredient of many Asian cuisines and has a more assertive flavor than the common sweet basil; its spicy aroma is a cross between cinnamon and aniseed and that is why it is sometimes referred to as "anise basil" or "licorice basil".  This type of perennial basil grows into a vigorous bushy plants with pretty reddish purple buds and produces seeds that can be sown in spring for propagation.

Thai basil will grow to a height of two to three feet and after four full leaves appear, one can begin harvesting by pinching the leaves. Harvesting frequently and removing flowers gives the plant better growth as well as ensuring that the leaves will retain their fragrance and full flavor.

By providing the right conditions perennial basil will add beauty to your garden and delight your palate all year round.