DeBaggio was once called the best “Rosemaryologist in America” and his company, DeBaggio Herbs, was one of the most respected herb farms and nurseries in the Washington District of Columbia area. In 2000 he received a Herb Society of America Certificate of Appreciation. With Susan Beisinger he co-authored Basil: A Herb Lover"s Guide.
His work has been featured in the magazine The Herb Companion.
DeBaggio grew up and lived near Ashton Heights, Arlington, Virginia for much of his life. Prior to growing herbs in 1974, he was a journalist with the Wilmington Independent and the Northern Virginia Sun.
In 1997, aged 57, he was diagnosed with early onset He wrote two books about the illness: Losing My Mind and When lieutenant Gets Dark: An Enlightened Reflection on Life with By creating a public record of, and insights into, his decline. He wanted people to better understand and to encourage research and treatment of the illness.
In 2011 at its annual convention, The International Herb Association has named its annual book award the Thomas DeBaggio Award.