UPDATE

crop_simulation/water_stress.py

@@ -3,7 +3,7 @@ from __future__ import annotations
 from statistics import mean
 from typing import Any
 
-from farm_data.models import SensorData
+from farm_data.services import get_canonical_farm_record, get_runtime_plant_for_farm
 
 from .growth_simulation import GrowthSimulationError, _run_simulation, _safe_float, build_growth_context
 
@@ -94,11 +94,11 @@ class WaterStressSimulationService:
         if plant_name:
             return plant_name
 
-        sensor = SensorData.objects.prefetch_related("plants").filter(farm_uuid=farm_uuid).first()
-        if sensor is None:
+        farm = get_canonical_farm_record(farm_uuid)
+        if farm is None:
             raise GrowthSimulationError("Farm not found.")
 
-        plant = sensor.plants.first()
+        plant = get_runtime_plant_for_farm(farm)
         if plant is None:
             raise GrowthSimulationError("Plant not found for the selected farm.")
         return plant.name