High desert watering cycle

We live just outside of Santa Fe NM and have a courtyard Lavender garden. Around the house we have a variety of trees: established pinions and shrubs with new Juniper and Russian Sage. There is no grass. The irrigation is ‘drip feed’ with varying throughput at plants (typical 0.5gpm) and trees (typical 4-6gpm). At this time of the year we water both zones for 1 hour, once a week.

Should we stay with this old ‘rainbird’ cycle, or can we do a better job with our new rachio gen 2?

I would appreciate your help

If the former schedule works, I would stick with that. You can go with a monthly adjust. Santa Fe is a pretty barren place since nearly everyone removed grass.

In Phoenix, we have a great guide to our desert watering recommendations called “Water Use It Wisely”. It’s not high desert here, but certainly desert.


Maybe @sunny can comment here. She’s our big time expert, master gardener and I believe has experience with high desert and Rachio.

In case you do want to take a stab at applying the “Water Use It Wisely” recommendations with a Flex schedule check out this guide.


Thanks for the input, particularly the watering guide. It seems that my landscaping guys assumed a set time to water, with seasonal change, while managing amounts with various size and numbers of emitters. That approach has 2 zones, grouping Lavender, Rosemary and such together, and the outside trees and shrubs together. We are into second year and doing OK for the most part. I was hoping to get better efficiency but will settle for easier programming and the ‘app’ for control and confirmation. The current rainbird has proved problematic with seasonal change.

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You may want to try a flex monthly schedule, which is sort of a bridge between typical fixed scheduling, and flex scheduling. A flex monthly schedule will increase/decrease durations throughout the year to account for the changes in temperature throughout the year as the seasons progress.

If it turns out that you like this type of schedule, the next step would be taking the plunge and using our flex daily schedule, which constantly measures the moisture level of each of your zones, and waters only when water is needed!

Flex monthly sounds interesting.

This is what the landscaper suggested for both zones:
September, Weekly 45 minutes
October every 2 weeks for 60 minutes
November through January Monthly for 60 minutes
NO mid-January through February
Mid-March. April Monthly 90 minutes
May every 2 weeks for 60 minutes.
Then see if you need to increase to 60 minutes weekly June through August.

Can I do something like that or even treat the 2 zones separately??

I don’t know about Santa Fe, but in Phoenix I’ve never trusted these types of recommendations. The landscapers I’ve experienced will make blanket recommendations like this without considering the vegetation type, emitter flow rates, or maturity of your vegetation. I could be wrong and they made the recommendation specifically to your yard, but I’d be more comfortable with something like the “Water Use It Wisely” recommendations that take those factors into account.


I’m a bit late to this conversation, having just returned from northern New Mexico with a side-trip to the cool mountains of Colorado.:relaxed: 114° here today! Ugh. I’m going back!

@azdavidr offers some great suggestions and his precipitation rate calculator for drip is terrific! The “Water–Use It Wisely” site has some very good information.

@davidsantafe, you say the piñons are established. If that’s the case, stop watering them. Piñons are very hardy and drought tolerant. Over-watering the New Mexico state tree can kill it from root rot. These pines are native to New Mexico and a few other southwestern states and can live several hundred years. They thrive in the arid deserts and in the Santa Fe area, the average yearly precipitation is fine for an established tree. As long as Santa Fe receives the normal precipitation, the trees should be OK. If Santa Fe doesn’t receive rain, then a monthly watering will benefit the pines.

More importantly, pine needle scale has been observed around Santa Fe and those insects can cause damage to a stressed tree. If you notice evidence of the insects, then you might consider a horticultural oil, sometimes called dormant oil. Bonide is one brand that is OMRI approved. It’s basically a mineral oil that smothers the insects. I use it to control codling moth in my apple trees.

A chat with the people of Agua Fria Nursery (they are very knowledgeable and have been in Santa Fe for years) or the Santa Fe Botanical Garden would certainly be worthwhile.


When would you suggest backing off the water for a pinion (or a bristlecone, for which I have heard similar comments)? Planted a few of them, and they will be “established” in a year or two, but the pinions in particular are only 12" tall and I’d be more than happy to give them a little supplemental water to speed along growth, you know…

Is it really an issue of, the soil needs to be dry as a bone? Or do they just need a good solid dry-out after each watering? I certainly have seen the little pinions drooping when they are too damp for too long.

@davidsantafe, I’m on a fixed day schedule for my drip, but eventually plan on moving to flex monthly, which seems like the right fit for drip. Flex daily would be cool, and is nice for my lawn, but needs crop & emitter uniformity. Drip really counts on dialing in each plant at the emitter level. I think ET modeling dripline is perilous with limited ROI, because you will have so many different plants with different water use, root depth, and so forth.

A supplemental watering for young piñons would certainly help them off to a good start. Just remember that they are very susceptible to root rot and need to dry between watering.

Weather, of course is a big factor and depending on your location, I wouldn’t give the piñons supplemental water during the winter.

You planted bristlecones? Or am I mis-reading that post? I can’t answer questions about them. I do know that they are very, very, very slow growers and extremely susceptible to root rot. They coolest ones I saw were in the Great Basin National Park and they seem to thrive in the tough growing conditions there. One bristlecone was estimated to be 4,900 years old!

You certainly are a patient person! :wink:

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Ok, will do my best to ensure they get to dry out. Definitely not going to supplement in winter.

These are Rocky Mountain Bristlecones, related but not the same as the famous Great Basin Bristlecone. I mention them because I had indeed heard similar things to the pinion, about root rot. They do seem to be less sensitive than I imagine the Great Basin variety is; there are several ten feet tall on the edge of the park lawn near my house, which means they get irrigated.

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The efficiency gain and ROI was with there for me. The fact that you have so many plants of different needs on the same line is a function of the irrigation setup, exclusive of the controller program. In other words, you still have the challenge with a fixed schedule but you’re overcoming the challenge by overwatering some plants with a fixed schedule. If you have the patience to do the same with Flex it can be more efficient. I was watering my drip based shrubs every 4 or 5 days last July on Flex, and without touching the program I watered once in the months of December and January. I wouldn’t have kept up with making those changes through the fall and winter if they were in a fixed schedule.

EDIT:. An important exception is for any vegetation that you determine needs to be watered more than once per day, since Flex algorithms are limited to watering once in a 24 hour period . I have my pots on fixed for that reason.


I live down in Albuquerque and have had pretty bad luck with the flex scheduling and almost lost a bunch of plants like yours after trying Flex Monthly or Flex Daily (not sure which). With bone dry air and 100 F days, it wanted to water the bushes once every two weeks (whether, I guess, they needed it or not).

My recommendation is to use fixed interval with some reasonable interval and let Rachio adjust how long it should water each time. Then, as the year progresses, change the interval manually and adjust the duration. This would be analogous to Albuquerque’s “water by the numbers” advice for grass. (http://www.abcwua.org/Water_by_the_Numbers.aspx) The landscaper’s guess for how to apply that to your bushes was probably better than any advice you’ll get outside the region.

Thanks Michael. My biggest concern is how often it rains downtown Santa Fe, but not here (10 miles out). On the landscaper advice has worked so far, so I will keep with their interval/duration model, at least for a while. Even doing that will be way more convenient than programming rainbird.

Actually I am not even sure what bristle cones are. That just appeared in the thread at some point. At this point I with the interval/ duration mode. As you observed the emitters have all be set up for the specific plants and shrubs, and seem to work… at least so far after 2 seasons

Do you feel like you exhausted all of the parameters in Flex to be sure they weren’t set such that your bushes weren’t being watered as frequently and deeply as they should have been? I mention it because I had the same problem when I first tried Flex, but as I dove in I found that there were many variables that could create an issue with underwatering. I’m not intending to argue that your decision was not right for you, but I also don’t want to leave other people looking at this thread with the impression Flex can’t be made to work in New Mexico or any other state.

The cool thing about the Rachio implementation is that it’s based on equations and practices that have been a standard in the agricultural industry for years. As long as you have an idea of your plant’s root depth, water needs, soil type, etc., the equations will efficiently deliver water to your vegetation and keep it healthy. Get one or two of those key parameters wrong, and you very well may see the underwatering issue you described.

FYI, I found this interesting New Mexico irrigation reference. Head down to the section ‘Drip irrigation requirement’. You’ll see terms like Kc, ET, etc., which are all a part of the Flex calculations. The study is from New Mexico state, and the drip irrigation has data from the Farmington area.


Again, there’s nothing wrong with going the route of setting a fixed schedule if you don’t have the time or inclination to go with Flex. I just want folks to know that if they’d like a hands-off scheduler that operates at max. efficiency and keeps your vegetation happy, it is possible with Flex, regardless of whether or not you’re in a high-desert climate. The only limitation I’ve seen so far is for zones that need to be watered more than once a day, and I haven’t seen mention of that on this thread.

BTW @davidsantafe, I agree that if you’re concerned about being 10 miles from a reliable weather station that could be an issue. Should you ever experiment with Flex again you can see that in the zone’s ‘moisture table’. It will show you how many inches of water were reported, and if it didn’t match with what fell in your area you’d have your answer. I’m sure that remote areas without a reliable weather station nearby would be a challenge for Flex implementation. You can always get a personal weather station for your property, but that’s another investment in time and money to work out.


Be careful of this on ‘Fixed’ as well and be sure to turn off the ‘Weather Intelligence’ features, like ‘Rain Skip’

If you were by any chance using Flex Monthly, you could have easily had problems. If I had used it last year when we were in drought conditions, I would have had several dead plants. That said, I was happy with Flex Daily. I like what @azdavidr said.

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No, I did not dig into Flex scheduling. Actually I wasn’t able to find options to dig in on other than describing the zone (shrubs), drip nozzle type and etc. Then once I went into the part where you make a schedule, well, I didn’t see more options.

In my opinion, the fundamental design flaw is that the control architecture is entirely written with an open loop orientation. And this orientation forces the user to put in all these control variables you describe. Control variables are a good start but overall inadequate.

In the past, for example, I would manually water the plants when I noticed that they weren’t getting enough water. A good system design would notice me doing this and give me the option to water the plants more often or more deeply. This would “close the loop” around the most important control variable (perceived plant health) and provide a way to quickly get it right. In the actual system, what happens is that the Flex Schedule notices that I watered the plants and then changes the schedule to water it less. It acts as if it thinks “hey, he watered it, so now I won’t have to.” That’s totally silly.

It is conceivable that users could follow your advice and, when they see that the plants aren’t getting enough water, adjust all the control variable until it starts working well. I suppose that eventually they would learn enough about the system to get it right. My advice is that this is time in-efficient way to get the system working right. That the automation is best for people that enjoy that sort of thing. And that users are better off just setting down a schedule, taking advantage of things like “don’t water after a rain” and moving on. A few tweaks a year, and they will have a great looking lawn and low frustration getting there.