<p>The aim of the study was to evaluate the effect of selected agronomic factors (nitrogen fertilization, chemical protection, the application of a biostimulant, hydrogel, and supplementary irrigation) on the content of bioactive compounds and the antioxidant capacity of table potato tubers. The research hypothesis assumed that the applied agronomic treatments significantly modify the health-promoting potential of potato tubers. The research was carried out in 2020–21 on two edible potato varieties: Gardena and Denar. The results indicate that the factor differentiating polyphenol content is genotype. Of the tested varieties, in Gardena the content of these compounds was on average 23.8% higher. The effect of mineral nitrogen fertilization, chemical protection, the use of biostimulant and intervention irrigation on the tested parameters was also found to be statistically significant. The content of polyphenols was highest after fertilization at a dose of 150&#xa0;kg N ha^˗1 (Gardena − 3.105&#xa0;g kg⁻¹ f. m., Denar − 2.357&#xa0;g kg⁻¹ f. m.) and after full chemical protection combined with dressing tubers using a preparation containing silver nanoparticles (Huwa San TR 50) (Gardena − 2.888&#xa0;g kg⁻¹ f. m., Denar − 2.480&#xa0;g kg⁻¹ f. m). Moreover, the combined use of intervention irrigation and the Bioalgen S90 biostimulant was associated with a high content of polyphenolic compounds (Gardena − 3.038&#xa0;g kg⁻¹ f. m., Denar − 2.400&#xa0;g kg⁻¹ f. m.) and antioxidant capacity (Gardena − 7.99 mmol Fe²⁺ kg⁻¹ f. m., Denar − 7.09 mmol Fe²⁺ kg⁻¹ f. m). This study provides a comprehensive assessment of the effects of integrated cultivation technology, including the use of a biostimulant, hydrogel, interventional irrigation, and optimized fertilization and protection methods, on the concentration of health-promoting compounds in Gardena potatoes. The results indicate that Gardena is a Polish-bred, medium-early variety with exceptional agronomic potential for European cultivation.</p>