Two field and postharvest experiments were carried out on the broccoli plant during the winter seasons of 2020 and 2021. This study was conducted to a: evaluate the effect of foliar spraying )two levels) with gibberellic acid (GA₃) 50 mg/L,100 mg/L, abscisic acid (ABA) 50 mg/L,100 mg/L, and seaweed extract 1000 mg/L,2000 mg/L on some traits of vegetative growth, heads, total yield, and some quality traits, b: to investigate the impact of past prior to harvesting treatments on broccoli perfect variety during different cold storage periods. The results showed that the treated broccoli plants were significantly superior in vegetative growth, head characteristics and total yield compared to the untreated plants (control). These treatments also had a positive effect on the quality characteristics of broccoli heads postharvest, with high significant differences compared to the control treatment, until the end of the cold storage period in both seasons. The treatment with the higher concentration for each treatment gave higher values for most of the studied traits. The results showed that spray with higher level of seaweed (2000 mg/L), was excelled in all studied traits until the end of the experiment. It was also the best treatment that reduced weight loss and maintained an excellent general appearance for up to 28 days. It preserved the content of broccoli heads of vitamin C, total soluble solids, total phenols content, and total chlorophyll. It also attempted to limit peroxidase enzyme activity during cold storage in both seasons. While the control treatment had the lowest values of all studied characters.