Hydraulic fracturing an individual reservoir fracturing layer of a subterranean formation to produce heterogeneous proppant placement is given in which pillars of proppant are placed such that the pillars do not extend the entire height of the fracture (for a vertical fracture) but are themselves interrupted by channels so that the channels between the pillars form pathways that lead to the wellbore. The method combines methods of introducing slugs of proppant-carrying and proppant-free fluids through multiple clusters of perforations within a single fracturing layer of rock, with methods of ensuring that the slugs exiting the individual clusters do not merge.