Before preservation, blanch Sophora japonica with boiling water, but keep it for one minute, then soak it in cold water for a while, then dry the water, spread it out to dry the excess water, then put it into a sealed fresh-keeping bag and put it in the refrigerator for preservation.

However, it must be noted that the taste of dried Sophora japonica is not so fresh, and it can be used to make steamed buns or jiaozi. Other ways to eat are ok, but the taste is much worse. Don't dry Sophora japonica in the sun, let it dry slowly in the shade.

You can also pick the Sophora japonica, wash the fresh Sophora japonica with clear water, and then scald it with hot water, or you can not scald it. Then put Sophora japonica in a cool and ventilated place to dry the moisture on the surface, put it in a plastic bag and store it in the freezer of the refrigerator, which can be stored for about half a year. Take it out when eating and melt it in warm water. It tastes delicious.

Fresh Sophora japonica flowers need not be washed with water. They can be directly packed into plastic bags, tied tightly and put in the freezer, which can be kept for one week. Put it in a plastic bag (preferably a sealed bag) and evacuate the air inside. It is better to have an air pump or a vacuum cleaner. Then it's sealed. If you don't put the refrigerator, you can put it in a basket, cover it with a wet cloth and put it on the cool ground. It can also be kept for 7 days.