A field experiment was conducted in the vegetable garden of the Horticulture and Landscape Engineering Department, College of Agriculture, Al-Qasim Green University during the autumn season of 2025-2026 to investigate the effect of different methods of potassium fertilizer application on growth and yield of cabbage. The experiment had two factors: how the fertilizer was applied, and two ways of doing this was by adding fertilizer to the soil or spraying fertilizer onto the foliage. The second factor involved adding potassium at five different levels: without adding water, adding potassium sulfate at a concentration of 1 g/L, and adding potassium sulfate at a concentration of [missing information].2 g L⁻¹, addition of high-potassium fertilizer at a concentration of 1.5 ml L⁻¹, addition of high-potassium fertilizer at a concentration of 3 ml L⁻¹. The experiment was laid out in a split plot design and means compared by least significant difference (LSD) at the 0.05 level of probability.

The results indicated that the application of high concentration of potassium (3 ml L-1) of fertilizer had significant effect on the studied traits. The K4 treatment showed the highest significant difference in terms of inplant height (44.90cm. plant -1), Leaf Leaf diameter (25.97)mm Plant-1Number of rolled-up sheets (35.0). In the case of plant-1, the measurements are as follows: Plant -1Head circumference (39.73) cm. Plant-1) Total plant yield (0.757) kg. Plant-1) Marketable head weight (1.090) kg. Plant-1) Chlorophyll content (68.8) spad uint.

The treatments also indicated significant superiority in fertilizing methods by potassium fertilization with the treatment superiorroadaddition Spraying in description plant height (45.12 cm. Plant -1)

The-ground based-addition method treatment was better in terms of characteristics such as Head circumference (43.19)cm. Plant-1),Number of folded papers(34.3 mm. Plant-1), Chlorophyll content(65.0spad uint) and Marketable head weight(0.845 kg. Plant-1), whereas in the case of DISTANCE method treatment, it was worse in every other characteristic.

The studied traits revealed significant superiority from the results of the interaction between treatments, where the combination treatment resulted in High potassium concentrationK4The method of application is by spraying. A1 In some qualities, plant height (46.07 cm. plant -1) Number of rolled-up sheets (35.3 Leaf. Plant -1Chlorophyll content (69.6spad unit)

Some characteristics, however, were significantly affected by the method of addition of soil, due to a high potash concentration. Leg diameter (27.90)mm Plant-1Head circumference (45.27) cm. Plant-1) Total plant yield(1.333 kg. Plant-1) Marketable head weight (1.009 kg. Plant-1).