Harwant's 58.32m effort was well short of London Olympics qualification B standard of 59.50m.
Russia's Daryia Pischalnikova won the event with 68.18m, third best performance in the world so far this season.
Results: Daryia Pischalnikova 68.18m; Alla Denisenko 58.45m; Harwant Kaur 58.32m.