Boyes scored one of St. Louis' three goals in the second period after assisting on Keith Tkachuk's 16th goal at 4:20.
T.J. Oshie and David Perron scored St. Louis' other goals.
Colorado averted a shutout when Chris Stewart scored his eighth goal this season at 11:56 of the first period.
Peter Budaj was beaten four times on 23 shots for the Avalanche, whose modest two-game winning streak ended.
Neither team scored on the power play on nine combined man-advantage opportunities.