Relevance and methods. Leek is one of the most promising onion crops for industrial cultivation in the Non-Chernozem zone, which has medicinal properties and high nutritional value. The results of studying the technological features of leek cultivation in the open ground of the Moscow region are presented. The studies were carried out in 2019-2020 on the territory of the “Vegetable Experimental Station named after V.I. Edelstein". We studied the influence of the feeding area of leek seedlings on the biometric parameters of plants and the quality of products. The object of the study is the variety Karantansky, experimental options: 1) seedling feeding area – 6 cm2 (control), 2) seedling feeding area – 8 cm2 , 3) seedling feeding area – 10 cm2 . The objects of research to study the content of ascorbic acid were leek varieties: late-ripening – Karantansky (standard), Bandit, Dobry Molodets, mid-ripening – Columbus, Hobot slona.Results. It is noted that the feeding area during the seedling period does not significantly affect the biometric parameters of leek plants: leaf area, plant weight, leek pseudostems diameter. Therefore, during the period of growing seedlings, from the point of view of rational use of the area in the seedling department, it is recommended to use the minimum feeding area – 6 cm2 . It was also found that the studied varieties accumulate ascorbic acid in different ways in various plant organs. The maximum content of ascorbic acid was noted in the leek pseudostems of the control late-ripening variety Karantanskiy – 23.6 mg%. The minimum values are for Dobry Molodets (11.8 mg%) and Hobot Slona (11.9 mg%).