Charles Dharapak/Pool/AP Photo

There's an old saying about green thumbs. And an old saying about sore thumbs. Hillary Clinton put the two together in Los Cabos, Mexico this week when for a "class photo" of G-20 foreign affairs ministers, she opted to wear a green suit.

The 30 other foreign secretaries and individuals in the picture wore white.

Which made Clinton stick out like a sore green thumb.

She laughed off the apparent miscue, however, and was smiling during the photos.  Asked about the fashion choice, a senior aide to Clinton said with a smile "she's a rugged individualist, what can I tell you."

Is this a trend? Last year at the Asia-Pacific Economic Cooperation Summit (APEC) in Hawaii, President Barack Obama snubbed a tradition started nearly two decades ago by the Secretary of State's husband, former president Bill Clinton. Instead of posing in traditional fashions of the host nation - think Hawaiian shirts, floral leis and hula skirts - the heads of state in attendance opted for their usual presidential garb.

Clinton also had important work to do in Mexico this week.  She signed an oil and natural gas sharing agreement with Mexican Foreign Minister Patricia Espinosa. A more formal G-20 meeting is set to occur in Los Cabos next month.