When the vegetables in the pot are tender, take everything out of the soup. Let them cool for a few minutes. Grate the beets, carrot and celery root, and put them back in the soup. Add the cabbage, the crushed tomato and the bell pepper also. Season the soup with salt, citric acid and black pepper. Its better to add the spices gradually and taste the soup all the time. Its should be only a bit sour. Also, if the beets weren't sweet enough, carefully add some sugar. Add the chopped dill.