Zi Su Ye
Botanical name: Perilla frutesens
Common name: Perilla leaf, Shiso
Literal name translation: purple perilla leaf
Family: Labiatae, mint family
Part used in Chinese medicine: leaf
Major Chinese medicine actions:
Releases exterior, disperses cold, promotes the movement of qi,
harmonizes the middle, calms the fetus in pregnancy
Photo Credits: (top to bottom)
Photo 1: Perilla frutescens; 12/2006; author SB Johnny; permission under GFDL
Photo 2: Perilla frutescens; 05/2007; author Les; permission under GFDL
Photo 3: Perilla frutescens; 09/2006; author Michael Becker; permission under GFDL
Perilla frutescens is native to China, Japan and India, growing on hillsides and mountains in sunny, fertile regions. The species has many varieties with many different leaf forms and colors ranging from green to red and purple. The leaves can be so large and red that they are reminiscent of a slice of raw beef, hence one of its common names, “beefsteak plant”.
The most common variety used in Chinese medicine has purplish green, serrated leaves and is sometimes mistaken for purple basil. The leaves have been shown to be high in anti-oxidants and have a much higher content of lutein and beta-carotene than spinach. In Korea the leaves are pickled and canned and sold in most grocery stores, and in Japan, the leaves, stems and seeds are all used in cooking.
Perilla is a pretty, aromatic, annual garden plant, which attracts butterflies and is frost tender, hardy to USDA zone 8. Zi Su Ye is used medicinally in a wide variety of situations and in one interesting clinical study from China, perilla leaves were used to treat warts in 20 subjects. The fresh leaves were rubbed on the warts for 10-15 minutes then laid on the warts, covered, tied with a cloth, and left for the remainder of the day. After repeating this procedure for 2-6 days, the warts soon resolved in all 20 patients.
Growing and Propagation
The plant is easy to grow, becoming 1-3 feet tall and wide and blooming from late summer to early autumn with lavender pink flowers on long 10-inch spikes. It does well in most garden soils, preferring full to part sun and moist, well-drained soil. It does not withstand drought-like conditions well. The foliage will become deep burgundy when grown in bright sun light, otherwise in a shadier environment the leaves will be olive green. Rich soil and adequate moisture will enhance the growth of the plant considerably.
After flowering, seedpods are formed and upon shaking the dry seed stalks, they sound like a rattlesnake, therefore another of its other common names, “rattlesnake weed”. Seeds can be collected in autumn as soon as they ripen. In the spring when planting, they should be covered only lightly with soil. Germination is quick and seedlings survive well in a protected spot. The seed has a short viability and should not be used when over a year old.
Harvesting and Preparation
Leaves can be harvested when they are at their fullest from June to the first two weeks of September when the flowers are open. The whole plant is cut and dried. For medicinal use, the best quality herb consists of large, whole fragrant leaves, without stalks. The seeds, Su Zi, are also used in Chinese medicine.