This much watering!?

Schedules & Zones Flex Monthly
1

This schedule seems way out of bounds, but I don’t have data or experience to back this feeling up. Here are the details of my situation:

• new build, lawn soil was clay from the overdig (I didn’t know at the time we should have hauled it off)
• I amended with grade a topsoil to about 3 inches around and tilled that hardpan as best as I could
• got it hydroseeded about 8 weeks ago
• very hot & dry summer here in Colorado Springs
• growth has been slow, coverage is still thin, but it is otherwise healthy
• up until last week I had been following instructions for hydroseed and watering in small amounts 3x/day every day
• last week I decided to switch to the Flex Monthly schedule type on M,W,F only (per my restricted watering schedule)
• today I adjusted the advanced settings after reading some info here

I have 4 zones, some overlap each other, all nearly identical. Nozzles are Hunter MP Rotators all around. Here are the basic settings for one zone, again very representative of all zones:

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Here are my advanced settings:

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settings_21384×1584 92.9 KB

And here is the resulting schedule:

resulting_schedule
resulting_schedule1372×1144 33.4 KB

This seems like waaaaay too much to me, but I’m a newbie to this controller and this much involvement in my lawn. What do you guys think?

2

Your root depth is probably way off. Less than an inch? That’s the first thing I notice.

Why flex monthly instead of flex daily?

How often does it show it actually watering.

And you might want to slow how fast you go from three times a day to every so often. I’d have cut back to two times a day for a week then once a day for a week then move to flex daily myself. Something to consider.

1 Like
3

I estimated that root depth b/c of the grass is only a couple of months old (from seed), the ground is fairly hard, and growth has very slow. Should I just get a shovel out to check in a few spots?

Why flex monthly and not daily? I don’t have a very good reason other than it seemed a little less technical based on the description. Can you tell me what you’re thinking?

How often does it actually show it watering? Well, I’m restricted to MWF (unless I get a waiver). The schedule detail shows it rotating 2x through each zone during that schedule.

Good thought on slowing the transition. I might do that.

4

First, PROPS to you for amending your soil as you did. Wish I had.

Second, you’re allowed to water your new lawn 3 times every day, but have a M,W,F watering restriction? As inkahauts mentioned, that is an extreme change for your new grass, and I’m not sure it would survive it.

As to the watering time, according to the National Weather Service Weekly FRET your lawn currently needs about 1.2" of water per week (1.5 FLEX x 0.8 Crop Coefficient). Using your Crop Coeffient of 0.80 efficiency of 80% and Nozzle Inches per Hour of 0.4, that results in 3.4 hours or 204 minutes per week. Watering 3 times per week, that’s 68 minutes per time, so 58 minutes isn’t that bad. The above calcs are based on ACTUAL current temperature, which is running hotter than average (which is what Flex Monthly is based on), and that you’re East of Colorado Springs, where it’s really hot, not West toward the mountains.

Basically, Flex Monthly is ignoring your soil settings, and putting down what the average historic temperature conditions require. Going to Flex Daily (which you didn’t suggest, just mentioning) would require that you set your soil settings to MUCH different values, because the Root Depth is not realistic.

I think right now Flex Daily would have a tough time, because it tries /not/ to water when it can, but with your new grass, you will have to water AT LEAST 3 times per week IMHO. As to the root depth setting, that needs to be at least 2-3", not under 1". I realize your roots aren’t that deep yet, but you WANT them to go that deep, and deeper to 6" or so, and without deeper watering, they won’t. Watering only the amount that your variables indicate would only result in 0.16 x 0.95 x 0.50 = 0.076" of water. You’d have to do that 3 times a day to keep up with the current temperatures, which require 0.17" per day. And that would be every day.

Back to the original question, is 58 minutes of watering 3x per week too much? That’s 3 x 58 = 174 minutes per week. If you divide that by 7 days and 3x per day, that’s 8 minutes. Have you been watering your lawn 3x a day for 8 minutes? If so, that’s equivalent to the 58 minutes 3x per week.

Bottom line, after watering 3x every day, I’d back off that slowly, maybe to 1x or 2x every day, then every day, and only then go to 3x per week, of course increasing the watering times as you go along.

Sorry for the long novel; there’s a lot of things to cover.

5

I’d just set it to 2-3" for now, deeper later. For 2 reasons: You want roots to search deeper for water, and you want a reservoir of extra water to help stabilize the available water.

I LOVE Flex Daily, and would normally recommend it, but Rachio recommends it be used only if more than 4 days a week are available to water, and I think in your case it will be tough to work properly.

I haven’t heard of a Flex Monthly schedule watering more than once per day, except due to Smart Cycle & Soak, which doesn’t usually show up on a schedule. Are you saying that the schedule shows it will water 2x per day?

6

@rraisley Yes to the watering restrictions. I got a waiver to temporarily ignore the restrictions b/c of the new grass seed & can extend it if I want. The waiver allows me to water every day. Otherwise I go to the regular MWF restricted schedule. I have a really small water utility co that’s pretty easy to work with.

Your explanation and questions have been helpful. I have other questions b/c I’m interested in how it all works together. For now though, I’ve decided on your and @inkahauts recommendation to go back to daily watering at reduced frequency, maybe 2x/day. Our growing season is tapering off here, so I’ll keep on the daily schedule modifying it as we go along for another few weeks. I’ll revisit these questions as we get near next summer.

Question, b/c the daily schedule will be a manual setup what sort of time/amounts should I shoot for in this situation? (new grass, slow growth thus far, 0.4 in/hr precip, clay-ish ground even with amendments, etc)

7

I think that’s a very wise move.

If I have your location right as mentioned above, you should be applying at this time about 1.2" of water per week. For 0.4 in/hr and 80% efficiency, that’s 1.2 / 0.4 x 1.136 (Scheduling factor for 80%) x 60 = 204 minutes per week, or 29 minutes per day. Maybe a little less, as the weather has been very hot there lately, but it’s about to get cooler. I think I would:

  • Set up a Fixed Schedule, watering EVERY DAY, for all your zones, 28 minutes per zone. (I’m not sure why your West zone had less minutes - less sun?).
  • To water Twice a day, set up a Manual Cycle & Soak, with a Cycle time of 14 minutes (half of 28 for 2x a day, 1/3 for 3x a day), and Soak time of maybe 5 hours.
  • Under Weather Intelligence, make sure Seasonal Shift is ON. This will decrease the water applied each month as weather gets cooler (and increase it next spring/summer as it gets warmer).
  • Put ALL of your 4 zones on the same Fixed schedule, so they can mix up the cycle & soak times. Separate schedules prevent watering of other schedules while soaking.
  • In your case, I’d Start watering at maybe 10 AM, with another water (due to the soak) of 3 PM. Not a very efficient way to water due to evaporation, but it will help keep your grass from drying out during the day.
  • As your lawn progresses and grows deeper roots, you can eliminate the soak period and water earlier in the morning.
  • When you think your lawn is ready, you can go to M/W/F watering, using about 3/7 of the TOTAL weekly watering time of WHATEVER THE TIME IS THEN (due to Seasonal Shift it will be less than now).
  • Keep an eye on the lawn, of course, if it seems to dry or wet and adjust accordingly.

As you say, that should get you through the year, but with watering only 3x per week, you might be best sticking with it.

8

@rraisley Thanks for the detail. Super helpful to a newbie like me. :+1:t3:

My location is very near that. I’m actually on the north end of Colorado Springs.

And the West zone is in nearly full shade most of the day under 3 mature pines. That’s why the watering is a bit less than other zones. The rest of the lawn is in full sun.

9

Since you have a small utility company, could you ask them: If I use a Flex Daily schedule that waters just when needed, could I not follow the M-W-F restrictions? My county lets any Smart Controller that’s been certified as being used properly (I actually have a required yearly inspection) bypass watering restrictions because they figure you are watering correctly. It might be worth an ask.

Just looked at my tracking spreadsheet, and even in the really hot weather here in NC, I end up only watering 2-3 times a week.

10

Great idea, @Linn. Thanks!