Based on his colorful, lyrical, childlike landscapes of wildflowers, forests and Korea’s Mount Seorak, one might think South Korean artist Kim Chong Hak’s is far younger than his 88 years.

Performing Rachmaninoff's Piano Concerto No. 3 with France's Orchestra of the Republican Guard under conductor Bastien Stil in the round, Kim swept three other honors in addition to first place: the ...