Added this to the class where the dataSource() is and it fixed my issue.
final Properties hibernateProperties() {
final Properties hibernateProperties = new Properties();
hibernateProperties.setProperty("hibernate.hbm2ddl.auto", "update");
hibernateProperties.setProperty("hibernate.dialect", "org.hibernate.dialect.PostgreSQLDialect");
hibernateProperties.setProperty("hibernate.show_sql", "true");
return hibernateProperties;
}
Full example is here https://github.com/arose13/Heroku-Spring-Postgres-Example.
EDIT PS: For this line hibernateProperties.setProperty("hibernate.hbm2ddl.auto","update");
check out this stackoverflow question to figure out the best value if update
isn't right for you.