However, birds ingest the fruit, thereby facilitating its spread. Use as an ornamental? Japanese barberry (Berberis thunbergii) is a small to medium, dense shrub that was originally planted as hedges in landscaping but has spread to native habitats.Japanese barberry is capable of changing soil characteristics in order to help itself outcompete native plants and also has early spring leaf emergence that allows it to shade out any nearby competitors. Award-winning Berberis thunbergii 'Orange Rocket' (Japanese Barberry) is a compact, upright, deciduous shrub with small, vibrant coral-orange new leaves that change to mid-green in summer before turning brilliant shades of red-orange in the fall. Spread of Species: Escaped into the wild because people have planted it in places where it can get into the wild. Barberries have the ability to change the soil chemistry beneath the plant, making the site more favorable for further infestation. Why have people planted it? The cultivar also is indicative of the plant’s growth habit. At maturity, the Japanese Barberry has a spread, or width, of 4 to 7 feet. Tiny, scented, pale yellow flowers appear in early summer, but are insignificant in comparison to the foliage. Berberis thunbergii, the Japanese barberry, Thunberg's barberry, or red barberry, is a species of flowering plant in the barberry family, Berberidaceae, native to Japan and eastern Asia, though widely naturalized in China and in North America. The Japanese barberry will not grow to most of northern Maine and the northern U.S or hot south, FL, TX, CA, AZ, but it … Deer do not eat Japanese barberry because of its sharp spines.