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K2 is the mission concept for a repurposed Kepler mission that uses two reaction wheels to maintain the satellite attitude and provide ∼85 days of coverage for ten 105-deg2 fields along the ecliptic in the first 2.5 years of operation. We examine stellar populations based on the improved Besançon model of the Galaxy, comment on the general properties for the entire ecliptic plane, and provide stellar occurrence rates in the first 6 tentative K2 campaigns grouped by spectral type and luminosity class. For each campaign we distinguish between main sequence stars and giants and provide their density profile as a function of galactic latitude. We introduce the crowding metric that serves for optimized target selection across the campaigns. For all main sequence stars we compute the expected planetary occurrence rates for three planet sizes: 2-4R⊕, 4-8R⊕, and 8-32R ⊕ with orbital periods up to 50 days. In conjunction with Gaia and the upcoming TESS and Plato missions, K2 will become a gold mine for stellar and planetary astrophysics. ar X i