In the present study the flowering and fruiting of black cumin Nigella. sativa L plant were studied using certain elements (i.e., boron, sulphur and potassium) and some the growth regulators (i.e., Naphthalene acetic acid, Benzyl adenine and Paclobutrazol) as separated treatments as well as some of their combination.. Number of days required for first flower anthesis is being shortened with one, two or three days when compared with control. The only exception was that increasing of these days by only one day in case of pp333 at 1ppm and the combination of (B+ S at 50 ppm for each), as well as with two days in case of BA at 5 ppm + (B+S at 50 ppm for each). Reduction in days number reached about seven days in K at 500 ppm, BA at 5ppm and 25 ppm, meanwhile it was seventeen days in control. NAA at 10 ppm and BA at 5 ppm combined with boron and sulphur at 50 ppm for each were the most effective treatments for shortening that time required for first fruit setting than the control BA at 5 ppm, NAA at 10 ppm and pp333 at 1 ppm each combined with B + S (each at 50 ppm) gave highest significant increased of fruit number and their dry weight. Also, B at 50 ppm and pp333 at 1 ppm (each alone) gave high significant. The treatment of BA at 5 ppm + (B + S each at 50 ppm) exhibited the highest biological and economical yields (i.e., weight of dry seeds). Different treatments increased each of essential and fixed oils when compared with the control. Also, 5ppm BA gave the highest increase of both oils (1.43 and 34.9% for volatile and fixed, respectively). Also, nearly the same content was obtained from each of BA at 25 ppm, pp333 at 1ppm and (B + S) 50 ppm for each. As for nitrogen and the crude protein were increased in shoots with different treatments. Also, phosphorus and potassium were increased in shoots. in most cases With regard to NPK content in black cumin defatted seeds different treatments increased the percentage of each of these elements |