The results of a study of annual mixtures of spring oats with spring vetch, field peas, narrow-leaved lupine and spring rapeseed in the conditions of the northern territories of the Arkhangelsk region (Kholmogory district) in 2020–2021 are presented. In the field experiment, according to generally accepted methods, the growth, development and productivity of grass mixtures were studied. The soil of the site is soddy-small-podzolic sandy loam highly cultivated. During the growing season — June and July — the weather conditions differed: in 2020, favorable conditions were formed for the life of annual crops, and in 2021 — dry. As a result of the research, it was found that in the changeable weather conditions of the northern territories of the Arkhangelsk region, it is most preferable to create annual grass stands from varieties of spring oats and field peas intended for use on green mass. Such agrocenoses, at the stated stand density, allow to obtain from 6.31 t/ha to 7.31 t/ha of dry matter, 62.03–70.44 GJ of metabolic energy and 1.01–1.15 t/ha of crude protein. Plants of narrow-leaved lupine and spring rapeseed are upright, do not need support and are not subject to lodging, it is possible to regulate the structure of the crop, and, accordingly, productivity indicators by changing the ratio of sown components and the total density of plants. The use of spring rape in a mixture with spring oats ensures, regardless of weather conditions, the productivity of agrocenoses at the level of the control variant, which makes it possible to diversify the species assortment of crops and reduce the risks of adverse factors.