Harm made history at Hillside Golf Club when she rolled in eight-foot par putt on the 16th green on the 30th June 2018. It gave her a 3&2 victory over American Stephanie Lau in the Ladies British Amateur Championship, and she became the first German winner in the tournament’s history. The win gave her exemptions into the Ricoh Women’s British Open and Evian Championship, along with places in the 2019 U.S. Women’s Open and inaugural Augusta National Women’s Amateur Championship. Harm arrived at Hillside as German champion, after winning the German International Amateur earlier in the month. The University of Houston player finished the 2017/18 college golf season as the American Athletic Conference Player of the Year after a season that saw her amass seven top 10 finishes, including runner-up in the LSU Tiger Golf Classic.