Formal box hedges have been used for many centuries in Europe and are still used in many parts of the world. Box plants are very long lived. If left untrimmed, they can grow quite tall but for hedging are usually kept under 3ft high. There are several varieties in use for hedges. Box plants need clipping only once or twice a year (for a more formal hedge they should be pruned as often as needed to maintain its shape). Start gently pruning box at a young age to make sure that the plants bush out from low down and create a dense solid shape. Otherwise they can take on a sparse look. These are a first-rate hedging plant, giving well-defined, evergreen topiarized shapes. Hardy to 5 degrees Fahrenheit and year-round foliage. For dense compact growth, plants should be planted in either full sun to part shade. They will tolerate partial even total shade. Tolerant of poor soils, boxwood does best in well-drained soil with plenty of decayed organic matter. Thrives on lime and chalk soils.