Like the rest of his friends, after the defeat of Voldemort Neville decided to repeat his seventh year and take his NEWTS. He received an O in Herbology, and average marks in everything else. While in his seventh year, he and Luna dated for a few months, but they broke up after deciding that they were better as friends. They remained on very good terms with one another.
Upon leaving Hogwarts, he took a job at Helen's Herbals, a place that bred and sold magical plants for use in potions. He had been working there for a few years when he heard that Professor Sprout was retiring, and the Herbology teacher post was open at Hogwarts. While he loved his hands-on job at Helen's Herbals, Hogwarts held such good memories for him that he felt he had to try applying for the position. His interview went well and he started teaching in the autumn of 2008. He was delighted to find that Harry Potter started teaching Defence of the Dark Arts at the same time. Five years later McGonagall left and he was made Head of Gryffindor, despite insisting at first that Harry should take it.