Answer: Unfortunately, I have been unable to locate a source for a dahlia named Thomas Jefferson. I did, however discover a source for a dahlia called Thomas Edison. Old House Gardens carries it, along with several other antique varieties. You might wish to contact Old House Gardens ( http://www.oldhousegardens.com/ ) and see if they might be aware of a source for the one you are seeking because old dahlia varieties are one of their specialties. I'm sorry I can't be more helpful.
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