Pick one category for the following text. The options are - company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work. Buddleja 'Longstock Silver' -  Buddleja 'Longstock Silver' is possibly unique as a sterile hybrid cultivar grown entirely for its foliage. Raised by Peter Moore Chief Propagator at the Longstock Park Nursery in Hampshire England the cultivar is the result of a crossing of Buddleja crispa var. agathosma and Buddleja alternifolia 'Argentea' released to commerce in 2010.
The answer to this question is:
Plant