This research was taken place in a glasshouse, at the Nursery of Ornamental plants, Fac. Agric., Minia Univ. during the two seasons 2022 and 2023 to study the impact of compost at 0.0, 170, 340 and 510 g/pot and mineral NPK fertilization (control, 3, 6 and 9 g/pot; 4:1:1) addition to their interactions on growing characters and chemical constituents of Dieffenbachia seguine plant.
 Data showed that all examined traits of vegetative and root growth (plant height, stem diameter, leaves area and 
number/plant, aerial parts weights in addition to roots number and its fresh and dry weights) as well as some chemical 
compositions (chlorophyll a, b and carotenoids and NPK%) were statistically enhanced parallel with rising compost level 
relative to control. Sequence, the level of 510 g compost /pot was greater than other used two levels. Also, all mineral NPK fertilization significantly improved in all abovementioned traits. The best interaction treatments were supplying Dieffenbachia seguine plants with compost at 510 g/pot and fertilizing plants with 9 g mineral NPK (4:1:1) /pot.