In order to investigate the effects of increasing soluble phosphorus (P) on SEED production and quality of black SEED (Nigellasativa L. ) in a calcareous soil, a field experiment was conducted at Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, in 2013. Field experiment was conducted as factorial layout based on a complete randomized block design with four replications. The fertilizer resources (vermicimpost (V) + Tiobacilus (T), Sulfur (S) + T, V+S+T and control) and three levels of P (0, 30 and 60 kg. ha-1) were the first and second experimental factors, respectively. SEED vigor was also assessed by radicle emergence (RE) test for further evaluation of the effects of P on mother plant on the quality of producing SEEDs. A germination percentage at day 4 was used as SEED vigor test. The resources of soil amendment (V+T, S+T and V+S+T) significantly decreased the P concentration in coat, P percentage of coat to SEED and mean germination time. For instance, by applying V+S+T, P concentration in coat and mean germination time were decreased by 18 and 10%, as compared to control treatment. However, 1000 SEED weight, SEED vigor, P concentration in embryo and SEED were significantly increased by applying the resources of soil amendment. There was a significant negative relationship between 1000 SEED weight and P concentration in coat (R2= 0. 66 **). It seems that under P-deficient conditions in soil, mother plant prefer to produce more longevity SEEDs, instead to increase theSEED vigor, by increasing the P allocation to SEED coat