Long-term changes in the optimum planting date of gladiolus in southern Brazil

The objective of this work was to test long-term trends in the planting date gladiolus ensure marketing these flowers on Mother’s Day and All Souls’ Santa Maria (latitude: 29° 43’ S, longitude: 53° W, altitude: 95 m), Rio Grande do Sul State, Brazil. Minimum maximum air temperature data from 106 years were used (1912-2017) simulate optimum indicated through PhenoGlad model, aiming harvest floral stems for both market dates early, intermediate I, II late cultivars. homogeneity historical series tested using run test, trend by Mann-Kendal test. magnitude estimated with simple linear regression, descriptive statistics calculated. For Day, there no that implied a change any development cycles. positive only early cycles I II; thus, increase delay 9.2 days, 9.5 days 6.9 date, respectively, indicating shortening cycle occurred, mainly winter/early spring.