Employing energy harvesting to power the Internet of Things supports their long-term, self-sustainable, and maintenance-free operation. These energy harvesting systems have an energy management subsystem to orchestrate the flow of energy and optimize their achievable system performance. Numerous such algorithms for a single harvesting-based system have been proposed. When envisioning the joint use of multiple distributed energy harvesting nodes in a single application, the performance and behavior of the distributed system depends on the mutual energy availability and therefore energy management of all nodes. We propose to perform the energy management of multiple distributed energy harvesting nodes jointly and thus, optimize the distributed system's performance as opposed to the performance of each energy harvesting node individually. We demonstrate the novel joint optimization in a scenario with multiple energy harvesting nodes and observe that the distributed system's performance improves by 28 % compared to when each node's energy is managed individually.