Research objective was obtaining high effi-ciency of a feather onion (Allium sulfur L.) in the closed agroecosystems of Krasnoyarsk agglomera-tion and an assessment of influence of some min-eral fertilizers on its morphological parameters. On-ions are vegetable culture which is more exacting to mineral food, when forming green material the main role is played by nitrogen. The results of a la- boratory trial for an assessment of the influence of these mineral fertilizers on receiving a feather of onion for grades Shtutgarter, Red Baron, Tsentu-rion and Sturon were presented. Onions were grown in glass capacities, of 0.5 l, within 21 days, at room temperature, day lighting. Experiment time: March, 2015. It was carried out the 3rd frequency. The experiment was made in four options: 1 - wa-ter without impurity (control); 2 - Knop solution; 3 - ammofoska; 4 - nitroammofoska (azofoska). As reagents solutions «Knop», ammofoska, nitroam-mofoska (azofoska were used). Control was water without impurity. By the results of research it was revealed that the greatest length of onions feathers of a grade Tsenturion was observed on a nutrient medium of «Knop» that confirmed its most benefi-cial influence on efficiency of onion. The use of fer-tilizers of nitroammofoska (azofoska) and am-mofoska had positive effect on this culture. Ni-troammofoska (azofoska) won in relation to fertilizer of ammofoska and as in an azofoska of active in-gredient it was more than in ammophos therefore it was the most productive top dressing for cultivation of onions. Fertilizers of a nitroammofoska (azofos-ka) and an ammofoska were less expensive and by efficiency concede to Knop solution a little. They make favorable impact on cultivation of onion and they can be applied to fast development and cul-ture maturing.