I recently got a Rachio 3, and right now I am running it in simulation mode (no valves connected), to get a grip on the various settings. I thought it may be useful for other newcomers to share my experience with the process.
I have a Personal Weather Station on my roof which is online at Weather Underground, so the goal is to see if Flex daily will produce good results adapting (at a minimum) the watering frequency to seasons and rain, and ideally to temperature.
I use drip irrigation for all the plants (2 zones) and sprinklers on a small patch of lawn (1 zone). Based on my past experience, my estimate for the drip irrigation watering time is 45mn to replenish moisture at the required depth. For these I usually watered from every 3 days in the summer to every 7 days end of fall (before any rain). For the Lawn, I usually ran it for 20 to 25mn, from every 2 days in the summer to every 7 days end of fall.
Setting up so far went like a breeze, the Wi-Fi setup is one of the easiest I have encountered so far with a variety of Wi-Fi connected devices, congrats to Rachio for that!
I was also pleased to see that Weather intelligence plus automatically found and proposed my Personal Weather Station as the top choice for single weather station settings.
Setting up the zone was also straight forward, I selected Perennials for the Plants zones, and warm season grass for the lawn patch. I used the default Loam for the soil as the landscaping is less than a year old so all soil was newly added.
I was glad to see there was an option for drip irrigation, so selected Drip line (which is what I use) for the Plants zones. My zones include plants in the sun and some in partial shade, so I set Exposure to “Some Shade”.
Then I went and created the Schedule using Flex Daily, and that produced the watering time. For the lawn the calculated watering time was 25mn, which is close enough to my past experience.
For the Drip irrigation Zone, it calculated 1h 49mn which was way too long, so I went and check which options would affect the watering time. Logically, for a given root depth, two settings appear to affect watering time, the soil type, as it determines how fast water will reach to the root depth, and in Advanced, the Nozzle In/hour setting. The default in/h for drip irrigation “drip line” appears to be 0.5 in/h and that seems to be under estimated. Average drip lines will have a drip emitter every 9 inches which gives out about 0.4 to 0.6 gal/h, below are my calculation to convert that into in/hour
- Assuming a wetting diameter of 9 inches, it is a surface of 63.6 in2
- 0.4 gal/hour is the same as 92.4 in3/h
- A volume of 92.4 in3 over a surface of 63.6 in2 represents a height of 1.45 in
So 0.4 gal/h emitter spaced at 9” would correspond to a setting of 1.45 in/h.
I found out that putting in 1.2 in/h would produce a watering time of 46mn which is close to my experience so far, so I plan to start with that and see how it goes.
Then I checked which setting would affect frequency, and here also logically, the exposure does that as it drives evaporation. Unfortunately, in Flex Daily mode, Rachio does not predict a schedule beyond the weather forecast, so you can’t really anticipate behavior over the whole year. That is a pity, and I think it would be nice if Rachio used historical data to make a yearly prediction in Flex Daily mode (like they do in Flex monthly)
So to really see the Impact of settings on Frequency, I created a Flex Monthly Schedule. Using an Exposure of “Some Shade” it produced a frequency going from 3 weeks in the winter to 4 days in July August. My experience is that this would not be enough. Switching to an exposure of Full Sun did make the frequency go down to 3 days in July, so I will set it at that and see how what Flex Daily decides as we reach the warm days.
I noticed two problems with the Flex monthly Schedule
- First, Drip irrigation Zones and the Lawn with sprinkler had the same frequency which is not right. I tried changing the root depth of the lawn from 9 to 7 inches and the one of the plants from 10 to 12” but it made no difference.
What fixed the problem was to create separate schedules for the Lawn (sprinkler) and the plants (drip). Then the lawn created schedule was more frequent than the one for the plants (as it should). I wonder if that is a bug or if schedules can only produce the same frequency for all zones??
- Second the watering time got reduced significantly (less than half) when I switched from Flex Daily to Flex Monthly, which makes no sense to me as watering time should stay the same, and only frequency should slightly vary at this point.
So next step will be to watch what Flex Daily does in terms of watering Frequency, and also see if it will create different frequency for the drip zone versus the sprinkler zone. I will update this post as needed.
I will also made a separate post for problems and questions I have below