<p>This study aimed to identify domestically developed forage cultivars suitable for high-latitude marginal regions, evaluate their cold tolerance, and use optimally designed seeding mixtures to establish a stable pasture production system. A field experiment was conducted in Pyeongchang-gun, Gangwon Province, Korea from April 24, 2022, to October 14, 2023. Five orchardgrass (<i>Dactylis glomerata</i> L.) and six tall fescue (<i>Festuca arundinacea</i> Schreb.) cultivars were assessed for forage productivity and forage quality. During the experimental periods, the highest fresh-matter yields observed among the orchardgrass cultivars were found for ‘Amba’ (130,333&#xa0;kg ha^− 1) and ‘Luckyone 2ho’ (121,567&#xa0;kg ha^− 1), while ‘Greenmaster’ (114,000&#xa0;kg ha^− 1) recorded the highest yield among the tall fescue cultivars. Cold tolerance was assessed at Chungbuk National University under controlled conditions, with ‘Onnuri 2ho’ and ‘Luckyone 2ho’ exhibiting the highest cold tolerance among orchardgrass, while ‘Purumi’ and ‘Greenmaster 4ho’ performed the best among the tall fescue cultivars. A mixed-seeding experiment was conducted eight treatments (T1 to T8) to evaluate the effects of the seeding (T1 [50% reduction], T2 [100%], T3 [150%] and T4 [200%]) and fertilizer application (T5 [50% reduction], T6 [100%], T7 [150%] and T8 [200%]) rates for pasture establishment. With an increase in the seeding rate, the canopy coverage, and the fresh- and dry-matter yields, improved, with T4 achieving the highest fresh yield of 69,167&#xa0;kg ha^− 1. Higher fertility rates also promoted early-stage growth as well as early yield. However, yield differences among treatments generally decreased in the later stages of growth. These findings offer practical strategies for improving forage productivity and stability in high-latitude, marginal regions.</p>