Most American herbalists know ashitaba as the longevity plant (Angelica keiskei), a perennial plant native to Japan that has been used medicinally and as a food for thousands of years. It grows well in areas near seacoasts and is hardy to temperatures as low as 0 degrees Fahrenheit. The leaves and roots are edible---you can eat them either raw or cooked. Medicinal uses include this plant's use as a diuretic and laxative and it is also reported to provide support for the immune system (though never ingest it without discussing it with your doctor first).
Using the Ashitaba Plant
Purchase seeds from a seed catalog or online source (see Resources). Plant seeds in fall in a cold frame---spring planting usually results in lower germination rates. Provide sunlight and keep your soil moist.
Transplant seedlings into individual pots when they are one inch tall, or large enough to handle without damaging them. Use standard potting soil and keep your plants in these pots until spring. Then plant them in their permanent outdoor location, which should have full sun or partial shade and moist soil of any type.
Dry your ashitaba plant by cutting off flower spikes with leaves attached in late summer or fall, when the flowers are in full bloom. Bundle several flower spikes together, tie them with string or twine and then hang them from a clothesline in a warm, dark, dry, well-ventilated area. They should dry in seven to 10 days. Strip the dried plant material from the stems and store it in plastic zipper bags or tightly sealed glass jars.
Brew tea with fresh or dried ashitaba leaves, flowers and stems. To use fresh plant material, chop it into small pieces and then place one to two tablespoons of this material into a teacup. Then pour boiling water over it and allow it to steep for five to 10 minutes before you drink it. To use dried plant material, use only one teaspoon of the plant per cup. Steep in the same way as for fresh tea.
Fill gelatin capsules (see Resources) with dried plant material that you have ground to powder in a clean coffee grinder. Consult with an acupuncturist or other knowledgeable herbal practitioner to determine the dosage that is right for you.
Cut ashitaba leaves and include them fresh in soups and other dishes. The recommended amount is one leaf or shoot for every two cups of soup. Slice or dice the leaves and simmer in your soup for no longer than five minutes, or simply add them to the soup when it is ready to serve.