I haven't grown or used it yet, but plan to as it's a frequent ingredient in Japanese dishes, including sushi.

I love shiso, but it goes to seed too fast here. I would not use it the same way as I do Italian or Thai basil, but use it to flavor many Asian dishes, in sushi, in dipping sauce. It's used in pickled garlic and umeboshi plum. You can julienne it on salad, use it for decorative bed under tapas. Do you eat sashimi? You can make a nice dipping sauce with soy, shiso, garlic, lemon, sesame oil.

Commonly used in Japanese cookery, Perilla (Perilla frutescens), also called Beefsteak Plant or Shiso, has a unique lemon-mint taste. It comes in purple or green varieties. The green variety is mostly used with raw fish dishes, the purple is used to add colour to pickled plums or apricots. Both can be used in salads. Seeds are added to pickles.

Fresh Herb Pesto Salad
500g pasta shapes
3/4 cup olive oil
1/8 cup red wine vinegar
1 tablespoons lemon juice
1 clove garlic, finely chopped (optional)
1 cup cherry tomato halves
1/2 cup grated feta cheese
1/2 cup chopped parsley
1/2 cup chopped basil leaves
1/4 cup chopped purple perilla leaves

Cook the pasta, rinse in cold water, drain and place in salad bowl. Whisk together the oil, lemon juice, vinegar and garlic (if using). Place remaining ingredients on top of the pasta, pour dressing over and toss gently. Chill for 2 hours before serving.

Perilla Cordial
1kg red perilla leaves
750g sugar
250ml honey
1 tablespoon citric acid or lemon juice
salt
1800ml water

Sprinkle about 1 tablespoon salt over the perilla leaves, and rub it in slightly. Wash and drain. Bring the water to the boil, add perilla leaves. Boil for 2-3 minutes, remove from heat. Discard the perilla leaves. Add sugar, honey and citric acid. Pour into a sterilised bottle, cool, then store in the fridge. To use, add 1 part of the syrup to 3-4 parts of hot or cold water and drink.

Perilla Rice
2 cups medium or short grain rice
about 5 perilla leaves

In a bowl, rinse rice until discarded water is no longer white. Drain and put into a large saucepan. Add 2 cups of water, soak for 30 minutes. Meanwhile, rinse perilla leaves, and cut into slices. Cover saucepan and bring rice and water to the boil over high heat; add perilla leaves, reduce heat to medium. Simmer, stirring occasionally, until all the water has been absorbed. Cover and leave for 15 minutes. Serve hot, and either eat plain or with pickled vegetables.

Pickled Vegetables
3 pickling cucumbers, eggplant or other vegetables
1/4 cup salt
2 cups water

Dissolve salt in water. Place vegetables In a bowl, pour salt water over. Put a plate over the top and weight down with a heavy object. Leave in the fridge for about one week.

Zucchini with Perilla
500g zucchini
1/2 teaspoon salt
1 tablespoon unsalted butter or olive oil
1 clove garlic, finely chopped
2 tablespoons finely shredded perilla leaves
freshly ground black pepper

Cut the stems and bottom tips off the zucchini and slice them very thinly, or shred on a grater. Toss with the salt, then transfer to a fine sieve or colander and set it over a bowl. Leave for 15 minutes, then gently squeeze to extract some of the water. It will give off at least 1/2 cup. Melt the butter in a large frypan over moderate heat. Add the garlic and stir for about 40 seconds. Add zucchini and perilla and toss with tongs just until heated through, about 1 minute. Taste and season with pepper. Mint, basil or lemon balm can be used instead of perilla.

And yes, it self-seeds prolifically in the garden and quickly becomes a weed.