Shiso (Perilla)

A bushy annual two to four feet tall with square stems and broad, toothed, often ruffled leaves in opposite pairs, green, purple, or two-toned. Small white to purple flowers form spikes in late summer. The smell is distinctive: something between mint, basil, cumin, and citrus.

Shiso arrived in Japan by the 700s or 800s. Red shiso (akajiso) is packed with salted ume plums to turn them red as umeboshi, and the dried, salted leaves become the rice seasoning yukari. Green shiso (ōba) became a common garnish after it was grown commercially in the 1960s.

In Korea the related deulkkae plant is grown for its big leaves and for perilla seeds, whose toasted oil (deulgireum) is a staple. Chinese medicine uses the leaf (zǐ sū yè) for colds with chills and nausea, and traditionally with seafood meals, to settle the stomach.

Sow in warm soil after frost, in sun or light shade, and keep it watered. Pinch the tips for more leaves. It self-seeds heavily; cut off flower spikes if you don’t want it everywhere next year.

Green shiso, red shiso, and bicolor ‘Britton’ are Japanese types; Korean perilla has larger, flatter leaves. Grow it beside basil and cilantro in the kitchen garden.

Pick leaves as needed through summer; they are best fresh. Red leaves can be dried and ground. Seeds ripen in fall and can be pressed or toasted.

A tea of the leaves with a slice of ginger is an East Asian household drink for the start of a cold, and the leaves were chewed to settle a queasy stomach.

Serve green shiso with sashimi and sushi, slice it into noodles and salads, or fry it as tempura. Use red shiso for pickled plums, pink shiso juice, and yukari. Wrap grilled meat in Korean perilla leaves, or pickle them in soy sauce.

Leaves as seasoning, tea, and pickle color; seeds for oil and as a separate herb for cough. In Chinese medicine the leaf is used for colds with chills, nausea, and bloating, and for food poisoning from fish or crab.

Chinese medicine: acrid and aromatic, warm, entering the Lung and Spleen channels.

Shiso’s flavor comes mostly from perillaldehyde, which is found in much lower amounts in other perillas. The red color is an anthocyanin called shisonin. The leaves are rich in rosmarinic acid and luteolin, and the seed oil is one of the richest plant sources of α-linolenic acid, an omega-3 fat.

A few small Japanese trials tested perilla leaf extract high in rosmarinic acid for seasonal allergy symptoms, with some improvement, but the research is limited.

Shiso as food is safe. Some wild perillas contain perilla ketone, which is poisonous to cattle and horses that graze it; livestock owners call it “perilla mint” and remove it from pastures.

Perilla has escaped gardens in the eastern U.S. and is considered invasive in some states; deadhead it to keep it from spreading.