  We revisit the Swift-Hohenberg model for two-dimensional hexagonal patterns
in the bistability region where hexagons coexist with the uniform quiescent
state. We both analyze the law of motion of planar interfaces (separating
hexagons and uniform regions), and the stability of localized structures.
Interfaces exhibit properties analogous to that of interfaces in crystals, such
as faceting, grooving and activated growth or " melting". In the nonlinear
regime, some spatially disordered heterogeneous configurations do not evolve in
time. Frozen states are essentially composed of extended polygonal domains of
hexagons with pinned interfaces, that may coexist with isolated localized
structures randomly distributed in the quiescent background. Localized
structures become metastable at the pinning/depinning transition of interfaces.
In some region of the parameter space, localized structures shrink meanwhile
interfaces are still pinned. The region where localized structures have an
infinite life-time is relatively limited.
