Groom and groomsmen to wear navy suits, navy patterned ties, and brown shoes (probably differing shades of brown)
grey groomsmen suits - photo by Allie Lindsey Photography http://ruffledblog.com/san-diego-botanic-garden-wedding
This looks wonderful...
23 Elegant and Classic Champagne Wedding Ideas | http://www.deerpearlflowers.com/23-elegant-and-classic-champagne-wedding-ideas/
Buttonholes and pocket squares on same side...
Cranberry bridesmaid dresses and blue groomsmen suits | LiFe Photography
Wedding Ideas by Colour: Blue Wedding Suits | CHWV More
The Navy Blue Suit! Nothing is more versatile than a navy blue suit. #men #style http://timelessgent.com/how-to-wear-a-navy-blue-suit/
Navy groom suit with grey vest, burgundy knit tie and gumnut boutonniere | Raconteur Photography