The quality of light in plants causes many anatomical, physiological and morphological changes. This research was conducted to investigate the effect of supplementary potassium nutrition, lysine and LED light on quantitative and qualitative traits of branched rosette (Rosa Hybrid L.), variety Candy Avalanch. The experiment was carried out in a completely randomized design with factorial arrangement with three replications using a soilless culture system during autumn 2017 in commercial Green Sayvan Greenhouse. Plants were cultivated in separate sections. Supplemental light treatments included: No artificial light, Application of 2 and 4 hours of complementary light (LEDs with 60% light blue color, 20% red light and 20% sunny light with a light intensity of 3600 lux) at the end of the day light period. Potassium nutrition treatments included: foliar application of distilled water as control, 1.71 mM of potassium sulfate and 1.71 mM potassium sulfate along with 2.05 mM lysine. The rose plants were established in perlite and grown using Johnson nutrient solution.. After establishment, the plants were exposed to the treatments for 3 months and then some plant parameters such as number of shoots, stem length, stem diameter, leaf number, number of internodes, peduncle length, peduncle diameter, squirrel diameter and calcification, as well as leaf chlorophyll and carotenoid content, chlorophyll fluorescence and concentration of iron, zinc, manganese, phosphorus and potassium in leaf were evaluated. The results showed that 2 hours of supplementary lights along with potassium and lysine application produced the highest average length of stem (79.5 cm) and internodes. The lowest stem length average (55.5 cm) was observed in control. Also in 2 hours light in combination with K and lysine application the highest total, a and b chlorophyll content and carotenoid were measured, while, the lowest total, a and b chlorophyll content and carotenoids were observed in control. In conclusion the Candy Avalanch variety showed the best performance under 2 hours of supplementary light plus K and lysine treatment over other treatments. Keywords: Branched rose, Rossette Hybrid L., LED Light Supplement, Potassium Nutrition, candy avalanch, Chlorophyll Leaf,, Carbohydrates