Evolutionary breeding method by creating composite cross populations (CCPs) can increase resilience against environmental variation. In 2021 two heterogeneous spring wheat populations (CCP1 and CCP2) created in Latvia, mixtures of their parent varieties (Mix1 and Mix2), four heterogeneous populations from abroad (Denmark and Germany) and 11 spring wheat varieties were evaluated under organic farming system in three locations – in research centres (RC) in Priekuļi and Stende and farm “Brīvzemnieki”. Grain yield and quality (TGW, protein, gluten content, and volume weight), nitrogen use efficiency (NUE) and weed suppressive ability were tested. The results of investigation showed that grain yield and quality differed between variants and investigations places. Grain yield of local CCP2 (2.3 t ha-1) surpassed significantly (p<0.05) average trial yield in Priekuli RC, CCP1 (4.3 t ha-1) had a significantly higher grain yield compared to the average in Stende RC, but heterogeneous population P2 (Denmark) (2.3 t ha-1) was superior at farm “Brīvzemnieki”. The highest grain quality (protein and gluten content, and Zeleny index) was for Danish population P2. NUE ranged from 33.9 to 49.9 g g-1 N with the highest for CCP1 and variety ‘Cornetto’. Local CCPs and the mixtures had a tendency to suppress weeds better than homogeneous varieties. [ABSTRACT FROM AUTHOR]