He started playing his father's drums, the conga drums. Many musicians came in and out of his home at a young age. Constantly surrounded by the sound of different instruments, he started to learn himself. At the age of four years old, he received two instruments: a piccolo and a short clarinet, in the key of E flat, so his fingers would reach. Since then, he always had a dream of being a musician.[6]
Justo Almario grew up during the glory days of Colombian music, with the big bands led by Lucho Bermúdez. Almario is related to Lucho Bermúdez (not by blood, but still family). When his mother heard that he really liked music she sent him to study with one of the family friends (that) already lived in Barranquilla, and that friend was the uncle of Lucho Bermúdez.
He studied at the prestigious Berklee College of Music in Boston, Massachusetts. When he was finishing his college education, Almario received a call from Mongo Santamaría to come and join his band. Mongo Santamaria was living in New York at that time. In Boston, they had a very important jazz club called the Jazz Workshop. And they would bring bands, all the famous bands, Miles Davis, Thelonious Monk, the Jazz Messengers, Mongo Santamaría and his band, to play at the Jazz Workshop, and they would stay there for a whole week, Tuesday to Sundays. He received a call from Santamaria, who sought an alto saxophone for the Jazz Workshop Boston "presentaciónen 71".
^Feather, Leonard; Gitler, Ira (18 November 1999). The Biographical Encyclopedia of Jazz. Oxford University Press. ISBN978-0-19-972907-4. "ALMARIO, JUSTO PASTOR GOMEZ, saxes, fl, cl; b. Sincelejo, Colombia, 2/18/49. Professional debut at 13 w. Alex Acosta Orch. in Colombia; at 17, tour. US w. “Cumbia Colombia” Band on cultural exchange tour. Studied at Berklee Sch. on full..."
^Fernandez, Raul A. (2006). From Afro-Cuban Rhythms to Latin Jazz. University of California Press. p. 97. ISBN978-0-520-93944-8. "During this period, there was a notable presence of Colombian talent in Mongo's ensemble. Besides pianist Eddie Martínez, Mongo recruited Justo Almario to play flute ..."
^Otfinoski, Steven (2007). Latinos in the Arts. Facts on File. p. 206. ISBN978-0-8160-6394-9. "Santamaria, Mongo (Ramón 'Mongo' Santamaria) (1922–2003) percussion player, bandleader, composer. A master of the Cuban drums called...Afro–Indio (1975), a potent collaboration with Colombian flautist and sax player Justo Almario."