Answer: Viburnum pilcatum tomentosum 'Watanabe' is a tough order to fill! The following sources carry everything except....
Perhaps a phone call can persuade one of them to track 'Watanabe' down for you:
Furney's Nursery (206) 624-0634, Sweetbriar Nursery (425) 821-2222, Julius Rosso Nursery (206) 763-1888, or Trees Seattle (206) 325-8119.
Good luck in your search!
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