Stress shadowing, a well-known effect that occurs in multi stage hydraulic fracture operations when the hydraulic fractures are placed close to each other, is an important challenge to obtain the highest estimated ultimate recovery (EUR) from a horizontal well. In industry, the most common practices of wellbore completion include three to five perforation clusters (i.e. entry points from the cased wellbore to the formation) per stage. Ideally, each cluster takes the same fluid volume during the hydraulic fracturing operations, leading to uniform stimulation of the reservoir. However, because of stress shadowing, some of the clusters tend to dominate others resulting in an unequal growth of the hydraulic fractures. Motivated by a need to validate and benchmark models used to select perforation spacing, fluid viscosity, injection rate, and so forth that will minimize the negative impacts of stress shadowing, our research focuses on laboratory experiments on the behavior of multiple, simultaneously growing hydraulic fractures. The experimental results show the impact of fracture spacing, fracture height, and number of fractures on multiple fracture growth. We demonstrate qualitative similarity in many respects to existing numerical simulations. However, we also find that certain predicted geometries are apparently less stable than others are when subjected to natural perturbations associated with laboratory experiments.