Two pots experiments were conducted during the two consecutive growing seasons of 2020 and 2021 at Beni-Suef governorate, Egypt, to compare the influence of biochar treatments (50, 100 and 200 g/pot) combined with foliar application of chelated and nano iron (250 and 500 mg L-1) on growth productivity and chemical composition of tuberose plants. The best result for vegetative attributes (leaf number /plant, leaf fresh and dry weights/ plant), flowering characteristics (flowering date, florets number/ plant, florets fresh weight/ plant, spike length and diameter in addition to fresh weight), vase life, bulbs productivity (number of new bulblets/ plant in addition to fresh and dry weights of the replacement clumps), oil %, photosynthetic pigments and total carbohydrates% in corms were obtained due to high level of biochar (200 g/pot). Regarding iron fertilization treatments, all of the above mentioned qualitative and quantitative attributes of tuberose plants were considerably augmented due to Fe-chelated at 500 mg L-1 followed by 250 mg L-1 then nano-iron at 500 mg L-1 while nano-iron at 250 mg L-1 gave the least values. Spike diameter did not appear to be appreciably changed by any of the four iron fertilization treatments.
In regard to the interaction between the two involved factors, the highest of the prementioned characteristics, as well as qualitative and quantitative characteristics values for the component of volatile oil, were obtained from fertilizing tuberose plants with the Fe-chelated at 500 mg L-1 in combination with biochar at 200 g/pot. Finally, adding biochar combined with chelated iron to tuberose plants obviously improved its qualitative and quantitative attributes.