  We study the time-like geodesic congruences, in the space-time geometry of a
Schwarzschild black hole surrounded by quintessence. The nature of effective
potential along with the structure of the possible orbits for test particles in
view of the different values of quintessence parameter are analysed in detail.
%wherever possible it is done analytically otherwise numerically. An increase
in quintessence parameter is seen to set the particles from farther distance
into motion around black hole. The effect of quintessence parameter is
investigated analytically wherever possible otherwise we perform the numerical
analysis to probe the structure of possible orbits.
  It is observed that there exist a number of different possible orbits for a
test particle in case of non-radial geodesics, such as circular (stable as well
as unstable) bound orbits, radially plunge and fly-by orbits, whereas no bound
orbits exist in case of radial geodesics. Using the geodesic deviation
equations, we obtain the corresponding deviation vector and find that the
quintessence assists the divergence of neighbouring geodesics in both the
radial and transverse directions.
