A field experiments were carried out in Aswan governorate, Egypt, during the two successive seasons, 2019 and 2020, to evaluate the effects of irrigation intervals, organic fertilization and NPK at the recommended dose (NPK_R) on growth, yield and some chemical constituents of henna (Lawsonia alba Lam) plants. The irrigation intervals were I₁ (every 7 day), I₂ (every 14 day) and I₃ (every 21 day), while fertilizer treatments were control (without), chemical fertilizer (recommend does of NPK_R), two levels of farmyard manure (15 and 25 m³/ feddan⁻¹ (feddan=4200 m²)) and two levels of compost (10 and 15 m³ feddan⁻¹). The results showed that, generally, by increasing irrigation intervals from one week to 3 weeks interval the growth characteristics, yield and chemical constituents, among all cuts, in both seasons were decreased. The highest values of these traits were observed when irrigating henna plants everyone I1, followed 2 weeks (I₂). Regarding NPK and organic fertilization treatments, all of them led an increase in the growth, yield and chemical constituents mostly. The best results when the addition of NPK_R followed by compost at 15 m³ feddan⁻¹. The combined effect between irrigation intervals, NPK and organic fertilization on henna (Lawsonia alba Lam) plants was statistically significant. In most cases, irrigation of henna plants every one week (I) with fertilization of NPK at the recommend dose or with compost at 15 m³ feddan⁻¹ were the most effective treatments, mostly concerning growth, yield, as well as chemical constituents.