How does soil moisture depletion work?


My schedule (flex daily rachio 3) I believe is set to 50% depletion. It is currently showing basically all zones at 25% depletion and not planning on running for 2 days with a 60% chance of rain tomorrow per weather intelligence plus. Grass looks ok currently. Does that sound right? I don’t really understand how depletion works.


My first recommendation, start with a zone in the front and zone in the back. Put the other zones on a more predictable schedule for now (flex monthly or fixed) if you like to try out flex daily for a couple weeks. Totally up to you with comfort level.

That’s actually maximum allowable depletion (MAD). MAD is the maximum amount of Plant Available Water (PAW) allowed to be removed from the soil before irrigation. If you went to zero it’s called permanent wilting where everything dies :frowning: I really would just leave that, industry standard is 50%.

Your zone “bucket” has 25% more moisture before it is empty and needs to be refilled. Looking at your graph, it actually looks pretty good. You’ll notice each day evapotranspiration occurs which decreases your soil moisture level until it hits zero. When we predict it hitting zero you will water again.

Here is some further reading to help understand some of the concepts.

Hope this helps.


To get fully indoctrinated.


Hi @franz,

When I first set this up i was a bit confused also, but read the info you provided and got it figured out (glad you guys have good writers). Since I like data, could the zone moisture graph show the total available moisture in the root zone, have a line at the allowed depletion level, and another line at the wilting point?

I ask because there have been a few times that my zones hit zero, and I’d like to know were it’s really at and if I need to do a manual run.