Sweet Bay, Allspice, Thai Lime…This trio of attractive and easy to grow herbal trees will take you on a culinary trip around the world. With a few recipes and the triad you can visit Mediterranean countries, Southeast Asia and Jamaica while sitting at your kitchen table.

Sweet Bay, known botanically as Laurus nobilis, is probably an "old faithful" in your kitchen, but making the switch from dried leaves out of a bottle to the fresh spice from your very own tree will give your recipes a real flavor punch. Also called Grecian bay or bay laurel, this tree is a native of the Mediterranean region. A required ingredient of classic bouquet garni, bay is a standard flavoring for soups, stews and bean dishes. Creative cooks also infuse it into liquids used in preparing puddings and dessert sauces. The leaves make a delicious tea either as the sole ingredient (young leaves give a spicy flavor with floral hints) or combined with Jamaican hibiscus tea (made from the calyxes of Hibiscus sabdariffa).

Bay Laurel is an historical plant found in mythology (Daphne was turned into a bay tree during pursuit by Apollo) and in European traditions. There is debate over the origin of the botanical name. Some authorities believe that the name is derived from the Latin "laus" meaning praise while others believe that it originated from the Celtic "laur" meaning queen. Regardless of etymological origin, the plant and name have come to be associated with victory. Winners of ancient Olympics were crowned with bay wreaths. Ancient Greeks also believed in the medicinal properties of the herb and hung a branch of bay over the door of a sick person to ward off evil and death. This lead to the practice of recognizing new doctors with a bay wreath called the "bacca laureus" from which the term "baccalaureate", referring to a university degree, was later derived.   Folk tradition holds that bay leaves will ward off cockroaches and other insects. Research at Kansas State University has supported this.

Laurus nobilis is reliably winter hardy only to USDA zone 8. In the more northern areas of its range it may freeze back to the ground. Fortunately, sweet bay is a slow growing plant that is easily grown in a container. Very attractive standard topiaries can be created with judicious pruning. The foliage is leathery and the common variety has ovoid, pointed, dark green leaves. Personal experience finds it to be an unpredictable bloomer in Texas. If it does flower the blossoms will appear in clusters of small, cream colored flowers with conspicuous stamens. Dark purple berries follow the blossoms. In ideal locations a bay tree may grow 10-50 feet tall but those grown in areas with freezes remain much shorter. A number of cultivars have been reported but only a few of these are found in commerce in the United States. Interesting ones that may be found with specialty growers are ‘Salicifolia’ or ‘Willow Leaf Bay’ growing 6-8 ft tall, and ‘Aurea’ with a golden leaf. These two cultivars may be seen on the grounds of Festival Hill, located in Round Top, Texas.  Sweet Bay is somewhat drought tolerant but will grow best with regular watering. Ordinary potting soil or well draining garden soil suits this plant. Twice yearly feedings with a balanced fertilizer should suffice.

Notoriously difficult to propagate, the easiest technique for the home grower is to root the suckers that often appear at the base of the plant. Semi-woody cuttings are slow to root but researchers have found that soaking these cuttings in water for 4-6 weeks then placing in a rooting medium gives the best success. The water must be changed daily during the soaking period. Seeds are the propagation technique used most often in commercial situations but germination rates are low and genetic variation is high producing plants that may vary greatly from the parent trees. Seeds must be planted while fresh. The difficulty in propagation leads to prices for bay plants that are higher than other herbs.

There is one caution with growing sweet bay; it is highly susceptible to scale infestations. Be ever alert! On small plants the insects, which appear as brown bumps on the leaves and stems, can be rubbed off with a soft cloth. More severe infestations may require spraying with horticultural oil. If scale is allowed to progress without removal the plants will weaken and black sooty mildew may begin to cover the leaves. To treat severe infestations in densely foliated plants at Festival Hill in Round Top, Texas, volunteers picked off all leaves by hand before the plants were sprayed. Although tedious and severe, the plants leafed out quickly following the treatment.

Looking once again at that spice shelf in your kitchen, you may find the fruit of another culinary tree that makes a superb houseplant. Allspice is the dried fruit from Pimenta dioica, the allspice tree. An English botanist from the seventeenth century, John Ray, first named these dried fruits for his impression that the flavor was a combination of that of cloves, cinnamon and nutmeg. Pimenta dioica is native to Mexico, Central America and Cuba and was first brought to Europe by the Spanish in the sixteenth century.

The whole dried fruits are used in pickling spices, marinades, as a mulling spice for wine and steeped in rum to make the Jamaican liqueur "pimento dram". The ground fruits are used with cinnamon to flavor meat in Arab and Turkish cooking, and in preparing a wide variety of desserts and spicy sauces. The "jerk" meat dishes Jamaica is famous for are marinated with a spicy mixture that includes either ground allspice fruit or leaves. The meat then may be grilled over a smoky fire of allspice leaves and wood. The leaves can also be infused into cooking liquids, added to stews and used to make tea.

The allspice tree grows from 30-50 ft tall in a tropical environment but is slow growing and will remain a nice houseplant. Grow your allspice tree in a large pot with rich soil and regular fertilizing and watering. The leaves are thin, shiny, dark green and will become reddish as temperatures approach 60° F. This is a signal that the plant spending the summer outside in a shaded location should be moved back indoors to a sunny window. Allspice trees are dioecious, meaning that male and female flowers are on separate trees. Older Pimenta dioica trees will bear panicles of fragrant white flowers in the spring and if you are lucky enough to have both male and female trees, small purple fruit may be produced. If so, pick them while they are green and dry them in the sun to produce your own allspice.

Allspice may be propagated from semi-hardy stem cuttings, but personal experience has shown this to be a slow and low yield process. Dipping the cuttings in rooting hormone before putting them in the rooting medium may help. If you are fortunate enough to have a plant that produces seeds, these will quickly germinate if planted as soon as they ripen, but it will not be known if seed grown plants are male or female for at least six years.

The final plant in our trio of culinary herbs would be considered by many to be the most exotic and provides a flavor unfamiliar to many Americans. The Thai lime will not provide juice for your margarita, but it will give dishes a floral and pleasant fragrance that can’t be produced by any other fruit, herb or spice. The botanical name for this native of Southeast Asia is Citrus hystrix. You may also find it listed under a variety of common names including Thai lime, wild lime, porcupine lime (descriptive for the large thorns on the trunk and branches), ma-gkrood (its Thai name) and Kaffir lime.

Thai lime is grown primarily for its shiny green, hourglass shaped leaves that give a perfumed citrus flavor to soups, curries, stir fries and salads. They are either added whole to the dish and removed before eating or sliced very thinly and used for salads and soup garnish. The leaves can be purchased dried, frozen or brined but the best flavor is found with fresh leaves. The bumpy, golf ball sized, dark green fruit have very little juice but the zest is used to perk up fish cakes and hot spicy soups. The flavor is very strong and the rind should be grated and then ground to a paste with other recipe ingredients. In Cambodian cuisine slices of the fruit are regularly included with other table condiments so that diners can flavor their meal with a squeeze of sour juice.

Citrus hystrix is only reliable hard to 45° F although it may survive short periods of freezing weather. It should be grown in a pot and brought inside during freezes. (Be warned, it does have large thorns, that may limit the enthusiasm of neighbors and spouses if asked to aid in moving a plant.)  In tropical regions it can be planted in the ground and will become a small tree eight to ten feet tall. Plant it in rich soil and provide regular watering and feeding. Growing the plant in a location with afternoon shade will keep the leaves from developing a "bleached" appearance. Like other citrus plants it may be visited by egg laying giant swallowtail butterflies but personal experience shows that it is less appealing to them than oranges and tangerines. Thai lime may be propagated either by cuttings or by seed. Cuttings should be dipped in a rooting powder and then placed in a light potting mix. Seeds germinate readily when planted from ripe fruit. Sweet Bay, Allspice, Thai Lime…Add this culinary trio of trees to your garden and you will be singing their praises and taking your cooking around the world!

REFERENCES FOR THIS ARTICLE:
Bown, Deni. The Herb Society of America New Encyclopedia of Herbs & Their Uses. Dorling Kindersley. London. 2001.
DeMonteiro, Longteine & Katherine Newstadt. The Elephant Walk Cook Book. Houghton Mifflin Co. New York. 1998 .
Loha-Unchit Kasma. It Rains Fishes. Pomegranate Art Books. San Francisco. 1999.
Tucker, Arthur O. & Thomas DeBaggio. The Big Book of Herbs. Interweave Press. Loveland, Co. 2000.