Long-term dynamics and forecasts of cultivated area, yield and production of major Brassica vegetables in Türkiye

Türkiye’s vegetable Brassica sector includes traditionally cultivated cabbage and comparatively recent commercial crops such as broccoli, cauliflower and Brussels sprouts. This study examined annual cultivated area and production records for cabbage, red cabbage, Brussels sprouts, cauliflower and broccoli from 2006 to 2025 and generated conditional projections for 2026–2045. Yield was derived from production and cultivated area. Long-term changes were assessed using compound annual growth rates, the Mann–Kendall test, Sen’s slope and the Pettitt test. Naïve, autoregressive integrated moving average and exponential smoothing models were compared using a 2021–2025 holdout period and rolling-origin validation. Three scenarios evaluated the influence of the marked changes recorded in 2025, and production forecasts were reconciled as projected area multiplied by projected yield. Cabbage area declined by 21.8%, but a 61.8% yield increase resulted in 26.5% production growth. Broccoli showed the strongest expansion, increasing by 656.4% in area and 972.4% in production. Production also rose by 144.6% in cauliflower, 105.3% in red cabbage and 426.6% in Brussels sprouts. Under the moderated scenario, 2045 production was projected at approximately 567 thousand tonnes for cabbage, 286 thousand tonnes for red cabbage, 501 thousand tonnes for cauliflower, 383 thousand tonnes for broccoli and 5.2 thousand tonnes for Brussels sprouts. Broccoli projections were particularly sensitive to whether the 2025 area expansion was treated as persistent. The results indicate a gradual diversification of Türkiye’s Brassica vegetable sector, with cabbage increasingly dependent on yield maintenance and broccoli growth driven mainly by additional cultivated area.