With over 160 different cultivars of boxwood even the most trained eye would find it difficult , if not impossible to name the variety here. The most widely available in garden centers are the common boxwood, ( it can grow to 10 ' ) English, Japanese and Korean. The Korean boxwood is known for its cold hardiness and the most beautiful and hardy 'Green Velvet ' cultivar , is a mix of English and Korean. If you plan to keep the boxwood low , then select a variety hardy to your area that doesn't grown more than 2-3 feet.