Dataset: Mutualistic interactions amplify salt marsh restoration success.This dataset contains the data from a field experiment that was conducted from April 2013 till September 2015 to test the hypothesis that reciprocal facilitation may enhance salt marsh restoration success. We experimentally manipulated the interactions between cordgrass transplants and mussels in a 29-month full-factorial field experiment in a southeastern US salt marsh.The first data sheet shows data on cordgrass growth and recovery, mussel growth, and chemical porewater and plant characteristics averaged per experimental plot. The second data sheet displays data on mussel lengths and growth given for each individual tagged mussel.