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Is there any post discussing (or suggesting as a feature including) a crop water requirements (crop coefficient, Kc) based on time (date) which can be assigned into the future for a particular program? Perhaps Coupe Pete is working on this feature?
That would be immensely helpful for integration into OpenSprinkler for the intermediate gardener or homesteader with a goal of set it and forget it automation for edible crops like vegetables. My example is for central Florida, where the university extension has published several papers on irrigation, including:
How to Determine Run Time and Irrigation Cycles for Drip Irrigation https://edis.ifas.ufl.edu/ae500
Principles and Practices of Irrigation Management for Vegetables https://edis.ifas.ufl.edu/cv107
First, some crops at their early stages don’t require as much water, but as they grow they need more (which Coupe Pete rightly notes). The change in crop coefficient for vegetables as they grow, for example, is considerable (ranging from 0.2 to 1.0). Including within a watering program an estimated or expected changes in crop coefficient over time would be particularly useful for more precise irrigation for certain types of plants over a multi-month schedule or growing season.
Also important to determining proper run time for an irrigation event is the water holding capacity of the soil. In some ways, I think that’s currently just fine-tuned based on initial setup by a user, and may not require changing the code to account for soil type. Thought I note a soil moisture sensor may not accurately reflect overwatering and thus leaching from the soil and wasted water. This is especially important for setups including periodic liquid fertilization to avoid leaching macronutrients into the local water supply (e.g., algal blooms). The overall goal is precise delivery of water volumetrically, based on ETo and Kc. ETo appears to be already integrated thanks in large part to contributions from ShawnHarte. But Kc is dependent on the stage/age of the plant or crop, and I don’t currently see a way to integrate that into an advanced weather based program using evapotranspiration.
So, I guess I’m wondering if we can develop a plant-based crop coefficient into a program, where a user inputs Kc values based on time? I would love to contribute with some dev/programming work, but have neither the time nor skillset to efficiently do so. If Coupe Pete is already working on (or has finished) this feature, maybe I can help get the ball across the goal line.