Among the events calling for bento is the spring cherry-blossom viewing (hanami), which takes place almost everywhere in Japan as the cherry trees (sakura) begin to bloom. These celebrations provide a holiday mood for workmates, families and friends who gather on straw or plastic matting spread under the cherry trees. The corporate parties are particularly raucous as they are accompanied by vast amounts of alcohol. The foods presented during the cherry blossom holidays are often pink, the color of the flowers, and might include foods dyed with shiso leaf (beefsteak plant or perilla) or foods made with azuki beans, which lend a pink tint to rice and other foods. A popular sweet at this time is sakuramochi, or sweet rice balls with bean paste wrapped in a shiso leaf. Cherry blossom viewing is very informal, of course, and so finger foods and other casual foods are common. Along with a bento filled with things like inarizushi (see recipe below), a group might bring along a small hibachi to grill (grilled chicken on a skewer) or kushidango, sweet rice dumplings brushed with a sugar-soy mixture.
Cook rice as for sushi. While the rice is cooking, simmer the bean curd pouches for about five minutes over high heat in half the dashi, to which has been added one TB of sugar and 1 TB of soy sauce. Cook the carrots and burdock root in the remaining dashi broth until just tender. When rice is done, let it sit covered for five minutes. Drain the vegetables. Drain and let the bean curd pouches cool spread out on a platter.
The homemade bento most people know best is the school lunch box. This box has become regularized by practice and custom as mothers are encouraged to follow the culinary, nutritional and visual balance that epitomizes Japanese meals. Children carry lunch boxes in many schools in Japan and the correct lunches, according to nutritionists and school officials, observe the formula of something from the ocean, something from the plains and something from the mountains, meaning fish, fish cakes or paste, or seaweed, chicken, pork, beef, or egg, and vegetables and grains (usually rice). The lunch is also a symbol of the close relationship between mother and child, and should also demonstrate maternal skill in making food appetizing and attractive, encouraging children to eat healthily and be grateful. During war time, when many foods were scarce, workers and children's lunch boxes might contain millet, sweet potatoes or pumpkin, or, if the scarce and coveted rice were included, a single red pickled plum (umeboshi) embedded in the center of a rectangle of rice would symbolize the Japanese flag, the Hinomaru. This Hinomaru bento was thus supportive of the war effort both in encouraging a spartan diet and in the visual representation of a national icon. Today's school lunches are often hot meals served in the classrooms and are more likely to include stews, curries and breads than Japanese items like fish, pickles and rice. But where the bento comes to school with the child, in nursery schools and elementary schools, its homemade quality is said to embody the love of the hardworking mother, just as the wartime box evoked the national struggle. Mothers who buy ready made box lunches at convenience stores, or who pack sandwiches, might hear subtle criticisms from teachers, though some children actually prefer the store bought versions. Many housewives confess that making an attractive bento according to the formula school officials propound takes time and a lot of effort, and might find the school lunch liberating.
A bento's chief characteristics are that it be portable and that all the foods contained within be ready to eat. It is usually prepared for one person, with foods individually portioned. The container may be wood, lacquer, wicker, or now cardboard or plastic. In pre-modern times the foods were salted or dried, convenient for carrying or keeping over time. The main foodstuff is rice, whether wrapped in seaweed, shaped into rice balls, or packed into a compartment in the container. The first bento may have been the box used to pack rice and fish for transport. The first sushi were actually fermented preserved fish made in these boxes and layered with rice, far from the image of the fresh-caught fish associated with today's sushi.