Surfgrass Phyllospadix iwatensis has been declining in the past decades. Transplantation is considered to be the best option to restore the degraded surfgrass beds due to its low seed production. To develop a surfgrass transplanting strategy to increase transplant survival rate and also to minimize damage to donor beds when harvesting transplants, an experiment was conducted to assess the effects of rhizome and root trimming on transplant survival and growth. P. iwatensis shoots with different rhizome and root trimming treatments were planted in a subtidal area in Mashanli at the east end of Shandong Peninsula, China in September 2018, and after the transplantation, a bi-monthly sampling had been conducted for one year. The results showed that, at the early stage of transplantation, the transplant survival rates of all four treatment groups decreased to the lowest at four months after transplantation, and then gradually increased until reaching at least 103.2% in all the treatment groups at the end of the experiment, and the transplants with roots on both short and long rhizomes had a significantly higher survival rate than those without roots. The results also showed that, although the morphological measurements, as well as the above- and below-ground productivity varied greatly with time and among different treatments during the study period, most of them showed no significant differences between treatments at the end of the experiment. These results suggest that surfgrass shoots with roots and a short rhizome are the most strongly recommended transplant candidates, and those with a short rhizome without roots are also good candidates, which might help make full use of harvested plants, optimize transplant harvesting strategies, and hence minimize damage to donor meadows.