# First day

It must have said 0 on the 21st but regardless… Let’s just go 12%… Can you help me understand what 25% deleting means? I’m thinking it would stay closer to 75% moisture ( ie 100-25%)…possibly plus or minus a days depletion or so but in no case can I see how it would get to 12%…

well, it’s complicated. Several parameters there dictate the need of water. Water availability times root depth gives you total water need. Allowed depletion reduces that amount to the amount we’re going to be working with. That range becomes 0-100%.

So in reality, with an allowed depletion of 25%, a 0% on the graph is really 75% on the larger all water need scale. 0% represents 100 - allowed depletion, 100% represents 100. Not sure how to explain this better. The allowed depletion % changes what the 0-100 range means. The water availability times root depth times allowed depletion gives the range of water between 0 and 100. A lower allowed depletion % means less water range, meaning a faster swing between 0% and 100%. A larger allowed depletion % means a slower variation between 0% and 100% because there is more water to juggle with

Hi Jpershke,

I think this was mentioned above prior.

Rachio calculates your zone with an allowed depletion number somewhere between 0-100%.

• Mine is set for 50% on cool season lawn and I haven’t change it.

Rachio will calculate the Moisture of that zone to allow the bucket of water so to speak to deplete 50% of the way before more needs to be refilled by the irrigation.

However, as easy as that sounds, the moisture graph you see is then 0-110% I believe. Which is great. But that 0% isn’t an empty bucket it’s a 50% full bucket.

Rachio doesn’t use the same percentage scale there.

Here is the official documentation with some better analogies: What are moisture levels? (Flexible Daily Schedules)

There is also some great definitions of the advanced settings on this page although I would strongly recommend you don’t change any until you understand what they do. It took me a good season to dial my setup in from Tuna Can testing the zones for inches per hour, doing mason jar tests to see what soil actually was compared to looking it up on the geo surveys, etc. It is worth learning. How can I edit my Advanced Zone Settings?

Ok so I think I’ve got it. Moisture level isn’t an absolute measure (like a gas gauge) but vs. your depletion level. So by definition, moisture will always hit 0 (or something close) before irrigation runs.

Now, I think it is an overly complex way of doing it and, or poorly named but I get it now… Thanks.

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Yes, irrigation kicks in when you go below 10% and tends to water 100% of the needed water, but then subtracting the evapotranspiration for the day, you will not see it go from 10% to 110% in a single day. Takes at least two days, unless it rains enough.