@ECOBEARD The balance between too much and too little change… therein lies the rub, as they say. We’ve made our models of dynamic crop coefficients using the best available science and erring towards the Rachio default, i.e. a conservative interpretation of the amount of variability within a year.
This feature will be available to toggle on/off in the Advanced Settings for each zone. A customer may at any time turn the “dynamic” feature off, in which case the crop coefficient will be re-set to the default, which can still be manually adjusted to whatever they choose.
While it is hard to test the real affects of these coefficient changes, simulations have convinced us that the dynamic coefficient values will yield water savings in some regions and seasons. A prime example is fall watering in a steppe/ semi-arid climate like I live in here in Denver. Daily evapotranspiration can remain relatively high due to warm, sunny, and windy fall days, but cool season grasses just don’t need nearly as much water as they did in August, due to their own biochemistry and the receding sun angle. So the Kc value throttling down over the fall will save water in this case, while also more likely providing enough water (avoiding under-watering) in the peak ET months of July, August, and September.
We will announce more information about this feature soon, stay tuned!