Several members of the Piperaceae family grow well in Hawaii. The native peperomia, known as alaala wai nui, is pervasive in the islands. Piper nigrum, a vine that produces peppercorns for culinary as well as medicinal uses, grows well here also. Piper methysticum is a shrub-like plant known locally as awa and worldwide as kava. P. methysticum has a history in Hawaii dating from settlements as long ago as 800 AD.
Awa was brought to Hawaii by Polynesian settlers, likely from the Marquesas or other islands in Oceania. The original plants may have been distant relatives of P.wichmannii, a plant native to Papua New Guinea, The Solomon Islands and Vanuatu. Today the plant we know as awa is cultivated throughout tropical Oceania, which includes the islands of Micronesia, Melanesia and Polynesia. Though various parts of the plant are used in ceremonies and for medicine in some cultures, an infusion of the roots in water or coconut water, niu, is widely used as a relaxant here.
The genus name Piper is the Latin word for pepper, while the species name methysticum is derived from the Greek word for intoxicating.
In Polynesian culture, the beverage kava is taken as part of a ceremony or festival. Ancient Hawaiians also drank kava at the end of a workday. Alii had exclusive access to some of the strongest cultivars and enjoyed kava drinks frequently.
Today folks can sample the beverage at several kava bars in West Hawaii or can make their own from dried roots or kava powder. The roots gain potency over the years and should not be harvested before they are at least 2 years old. Digging up the root ball and using a power washer to remove all the soil, dirt and grit is step one in the harvest. Once the roots are completely clean, they can be chopped by hand or in a food processor. Making the beverage from fresh awa produces the best flavor and potency. Excess roots can be stored by refrigeration, freezing or drying.
The kavalactones are the causative agents of various effects experienced by kava drinkers. For information about kavalactones and the potency of different cultivars, read Ed Johnston’s book “Hawaiian Awa: Views of an Ethnobotanical Treasure.”
Kavalactones are released when the roots are dried, ground into a powder and mixed with water or juice to make a beverage. The beverage induces a relaxed sensation and numbs the mouth. Though some assign narcotic effects to kava, kavalactones are primarily known to only have sedative effects that can become somewhat hypnotic in large doses. Excessive consumption can cause temporary symptoms such as dry, flaking skin. Some studies of excessive use link kava to liver problems, but those have not been adequately replicated. Hawaiians use awa combined with other ingredients to treat physical problems including thrush in children as well as kidney disorders, chills and headaches among adults.
The plant grows well in Hawaii and is an interesting aesthetic addition to a garden as well as offering a source of medicinal remedies. The striking appearance of the plant comes from the color and shape of the stems. They are jointed and have prominent nodes that look like knuckles with internodes of various lengths and colors. Depending on the variety, the stems can range from bright to dark green and spotted as well as deep purple, almost black. This sprawling, open shrub can reach 12 feet high in ideal conditions but can be maintained at around 4 to 6 feet in small gardens and smaller in a container.
The large heart-shaped leaves are another distinguishing feature. The leaves can be from 5 to 8 inches long and nearly as wide. A white spike of 1 to 4 inches containing tiny male flowers will occasionally appear. The female flowers will appear on a separate plant but are rarely seen. Vegetative propagation is the prevalent technique for reproducing awa plants.
Sanitation and proper irrigation is important to keep the cuttings from rotting or becoming diseased. A cutting of several nodes placed on top of a sterile medium that drains well is key to success. The cutting should be buried halfway into the medium. Cinders or perlite mixed with vermiculite or peat work well as a growing medium. Awa is sensitive to rootone and it should not be used. Light watering every other day should be adequate.
Ground layering can be successful as well. Simply take a node of the “mother plant,” leaving the stem attached, and secure it to an area of soil that is fairly clean. Maintain moisture to the area and watch for roots and shoots to develop from the node.
Once you have a new plant growing you can put it in a larger pot or move it into your garden. Place it in an area that is either partly shady or has full sun. Be sure the soil drains well and amend it with compost or other organic matter before planting. Allow space around the new plant for side growth as awa plants can spread to be as wide as they are tall.
Established plants need little maintenance, though some pests may attack them. Chinese rose beetles may leave holes in the leaves. Scale and spider mites can be attracted to weak plants. Maintain adequate water and fertility to keep the plant healthy and avoid most problems. Awa plants are susceptible to cucumber mosaic virus. Keep host plants including curcubits, melons and hono hono grass far from awa to avoid contamination by this disease.
Papaeleele is perhaps the most cultivated variety and one of the most potent. It is a low growing variety with dark purple stems and short internodes. Other popular cultivars include Moi which also has dark stems and medium length internodes. Nene is named for the appearance of the stem with lots of lenticels which give it a similar appearance to the feather pattern on a nene goose.
Amy B.H. Greenwell Ethnobotanical Garden in Captain Cook has many mature plants in the ground to observe and usually has some for sale as well. Many area nurseries sell young awa plants.
However you acquire your awa, know that you are installing a plant with a rich and varied history in Polynesia and one that will grace your garden with an interesting and culturally significant specimen.
Peter Van Dyke, the manager of Amy B.H. Greenwell Ethnobotanical Garden, contributed information and reviewed this article for accuracy.
Diana Duff is a plant adviser, educator and consultant living on an organic farm in Captain Cook.