1. An evaluation method for photosynthetic sample for evaluating a state of a photosynthetic sample with a photosynthetic function based on temporal data of a luminescence amount of delayed luminescence emitted from the photosynthetic sample and comprising: a characteristic value computing step of computing, for a plurality of time periods in the temporal data, characteristic values that indicate characteristics; an evaluation value computing step of computing an evaluation value by weighting the characteristic values; and an evaluation step of evaluating the state of the photosynthetic sample based on the evaluation value.