What drives the cost of moving to smart irrigation?

Your starting plumbing, far more than the software. If your blocks are already on drip or micro-sprinkler with independently valved zones and known per-zone flow rates, the work is instrumentation and configuration. If the orchard is on flood or on a single shared valve, the real project is zoning it, and that is capital work with a contractor rather than a subscription decision. The honest summary is that the control layer is the cheap part and the pipe is not, so any per-acre figure quoted without seeing your blocks is guesswork.

How long does installation take?

Software onboarding is usually days, not weeks: block boundaries, zones, and a flow rate for each zone. Physical work - latching valves, a gateway with cellular backhaul, and any probes you choose to add - depends on zone count and crew availability, and is commonly staged one block at a time across a season rather than done all at once.

Will it work with my existing irrigation system?

In most cases, yes. Smart scheduling sits on top of standard drip and micro-sprinkler hardware; you do not need to replace emitters or mainline. What Persea needs is that zones can be valved independently, and a flow rate for each zone - which you configure, because Persea does not read a flow meter. Orchards on a single shared valve get less benefit until they are zoned, because there is nothing to differentiate.

How much water can smart irrigation actually save?

Published field studies and grower reports commonly land in the 20-35% range for water applied versus a fixed-calendar baseline, but that band is an average across very different orchards and it is not a figure we have measured ourselves. The real saving on your blocks depends on how over-watered the worst zones currently are. We treat that number as something to measure per zone in acre-feet, not assume from a brochure.

What data do I need to provide to get started?

At minimum: your block boundaries, crop and rootstock, irrigation method, and a flow rate for each zone. Persea multiplies that rate by run time to get applied water, so it is worth setting from your own plumbing rather than leaving it on a default. Weather and reference evapotranspiration come from the weather service against your orchard coordinates, so you do not have to supply those. More history makes the picture better, but you can start with a baseline and let it refine as data accumulates.

Is there a minimum farm size?

No hard minimum, but the economics favor operations large enough that water and labor are real line items - practically, orchards in the tens of acres and up. Below that, the per-zone hardware can still pay off if water is expensive or constrained, but the payback is slower.

How accurate is ET-based scheduling?

ET-based demand estimates are well-validated for tree crops and are the backbone of University of California irrigation guidance. Accuracy improves when ET is corrected by on-site soil-moisture readings, which catch the cases ET models miss: a clogged emitter, a fast-draining sandy patch, or rain that did not reach the root zone. Pairing the two rather than trusting either alone is the right design, and it is the design we are building toward.

Does Persea decide irrigation on ET today?

Yes, and on the zones you have consented it acts on that decision. Today Persea pulls daily reference evapotranspiration, applies crop coefficients, shows you the resulting demand per block and plans regulated deficit on FAO-56. It also runs a daily water balance per zone and decides from it: advisory on every zone, and on consented zones it opens the valve itself. Consent is one affirmation, made under step-up authentication, covering the zones it lists for you at that moment; a zone added later stays out until you affirm again; every autonomous run is logged; and you can withdraw at any time, which also stops runs already in flight. The daily ET0 behind it is cross-checked against a second source: where the two disagree the balance runs on the lower figure and the engine will not act, and where the second source is silent that is not agreement either, so it reports rather than acts. Each zone has its own schedule and its own flow rate, and your schedules run - which is a different mechanism from the decision above, not the same one under another name. Persea opens the valve at the time you set, on your farm's own clock, and closes it on the duration you set; on the schedules you leave weather-aware a forecast-rain check drops the occurrence before anything opens and logs why, and a schedule you disable or delete while it is watering is closed on the next sweep. A schedule running is your own instruction being carried out. The engine acting is Persea's decision, on a zone you consented to, and it is the only one of the two that needs that consent.

Does it integrate with the hardware and software I already use?

Partly, and it is worth being exact about which part. Persea drives valves through an extensible device gateway, so common valve controllers can be brought in over a generic control pathway rather than a single proprietary stack - and that gateway is valve control only: it opens a valve, closes it, and reads its status. Not every valve controller has a driver written for it, and where a direct integration does not exist, manual logging still produces the records and scheduling you need to start.

Guide

Smart Irrigation for California Orchards

A practical guide to smart irrigation for California tree-crop growers: ET-based scheduling, soil-moisture sensing, SGMA compliance, cost-per-acre economics, and how it differs by crop - with honest numbers, not vendor hype.

Why California growers need smart irrigation

California grows the majority of the country’s tree nuts and a large share of its citrus, avocados, and stone fruit, and almost all of it is irrigated. That makes water the single largest variable cost most orchards can actually control - and the one under the most pressure. Three forces are squeezing it at once.

The first is regulation. The Sustainable Groundwater Management Act (SGMA) is moving growers in over-drafted basins from unmetered pumping toward reported, and increasingly capped, groundwater use. Allocations that once felt theoretical are now arriving as hard numbers from local Groundwater Sustainability Agencies.

The second is drought. California’s water years swing hard between wet and dry, and a dry cycle turns a comfortable surface-water allocation into a deficit that has to be made up from groundwater - exactly the source SGMA is constraining. The third is simply cost: surface water, pumping energy, and labor all trend up, and water priced in dollars per acre-foot rewards every acre-foot you do not waste.

Smart irrigation is the response to all three. Instead of running every block on the same calendar, it measures what each zone actually needs and applies only that - turning water from a fixed habit into a managed, measured input.

It is worth being clear about the cost of doing nothing. A calendar-irrigated orchard is not just spending more on water; it is spending it blindly, with no record of where it went. When a dry year or an allocation forces a sudden cut, that grower has no data to decide which zones to protect, so the reduction lands evenly - including on the young, high-value blocks that can least afford stress. The grower who already meters every zone makes that same cut surgically, sheds water from the lowest-return ground first, and keeps the orchard’s best acres producing. The gap between those two positions widens every dry year, which is why the timing of the switch matters as much as the switch itself.

How smart irrigation works

“Smart” gets attached to a lot of timers that are not. The real distinction is whether the schedule responds to measured demand and measured soil, or just to the clock. A genuinely smart system rests on three inputs working together.

ET-based scheduling. Reference evapotranspiration (ET₀) estimates how much water the atmosphere is pulling from a well-watered reference crop. It can be computed by the FAO-56 Penman-Monteith equation from weather at your own coordinates, and in California it can also be read from the state’s CIMIS network, which publishes a daily satellite-blended grid. Multiply ET₀ by a crop coefficient for your tree, canopy, and growth stage and you get the crop’s actual water demand for that day, in inches or gallons. This is the demand side of the equation, and it is the backbone of University of California irrigation guidance. Having two independent ways to get the same number is not redundancy for its own sake: it is what lets a system check itself before it acts.

Soil-moisture sensing. ET tells you what the tree wanted; soil-moisture probes tell you what it got. Sensors at depth in the root zone catch the things an ET model cannot see - a clogged emitter, a sandy patch that drains in hours, a rain that ran off before it infiltrated, or a hardpan holding water too long. Tension (kPa) or volumetric readings keep the schedule honest.

Weather integration. Forecast rain, heat spikes, and wind feed back into the plan so you are not irrigating ahead of a storm or under-watering through a heat wave.

Here is where Persea sits against that, stated as what it does rather than as what the category can do. A timer applies “15 minutes everywhere” regardless of soil, slope, or tree age. Persea works each zone on its own: reference ET and a crop coefficient give that zone its own daily demand, and run time is expressed in that zone’s own flow terms - gallons per minute, totalled per zone into acre-feet.

Be clear about what that gallons figure is. It is what a zone run applied, and what your irrigation cost is derived from - the run time multiplied by the flow rate you configured for the zone, or by a default if you have not set one, and not a meter reading. It is not what your SGMA reporting draws on; that comes from well usage you record against a well, and the zone-run records are kept separately. Persea does not read a flow meter, and it does not adjust a plan from soil-moisture probes. What it does check is the weather input rather than the water delivered: the reference ET behind every decision is computed at your own coordinates and cross-checked against a second, independent source before the system will act on it, which is what the How Persea helps section below describes.

Cost analysis and ROI

Irrigation is rarely a single line item - it is water, the energy to move it, and the labor to manage it. In California tree crops, applied water commonly runs in the range of 2.5 to 4.5 acre-feet per acre per year depending on crop, climate zone, and soil. At real-world blended water-and-energy costs, that is frequently several hundred to well over a thousand dollars per acre per year. The exact figure is yours to compute from your water bill and pump records; the point is that it is large enough that a percentage saved is meaningful money.

Field studies and grower reports of demand-based scheduling versus a fixed calendar commonly show 20-35% less water applied. We quote that as a range, not a promise, and it is somebody else’s measurement rather than ours: the saving comes almost entirely from the zones you were over-watering, so an orchard already irrigating tightly will see less, and one running a blanket calendar on mixed soils will see more. The discipline is to measure it per zone in acre-feet rather than assume a vendor average.

What that range is worth on your orchard is one multiplication, and it is worth doing before you talk to anyone. Take your applied water per acre, take your own blended cost per acre-foot from your water bill and pump records, and see what a fifth of it comes to across your acreage. That figure is the honest size of the prize; what it costs to capture is a conversation about your blocks, your existing valves and your hardware, not a number a web page can responsibly print.

The water line is also the easiest saving to see and rarely the largest, which is why the arithmetic above understates rather than overstates.

Pumping groundwater is energy-intensive, and every acre-foot you do not lift is electricity or diesel you do not burn, which moves with energy prices rather than water prices and often compounds the saving. Labor is the quieter line: a manager walking blocks to open and close valves, or guessing at run times, is spending hours that a zone schedule reclaims, and those hours tend to be the scarcest resource on a farm at peak season. Neither shows up on the water bill, which is why the water bill is the floor of the case rather than the whole of it.

SGMA compliance

SGMA pushes groundwater management down to local Groundwater Sustainability Agencies (GSAs), and the reporting they require is tightening. Many basins now expect growers to report extraction, and basins in critical overdraft are setting allocations measured in acre-feet per acre. Meeting those requirements on paper is hard if your only record is a monthly pump bill.

Persea keeps two separate records here, and it is worth knowing which is which. The extraction figures in the GSA pack come from well usage you record against a well, rolled up in acre-feet against your allocation. Every zone run is logged too - its start, its stop and the water it applied - but that is a separate record and does not feed the extraction figures, and its water figure is the run time multiplied by the flow rate you configured for the zone rather than a meter reading. Whether your GSA takes an estimate in place of metered data is theirs to say; ask them which. When an allocation lands, the zone records let you decide where to cut with intent - trimming the zones with the least return per acre-foot - rather than blanket-reducing the whole orchard and stressing your best blocks.

The trajectory matters here. Even in basins where reporting is still light, most Groundwater Sustainability Plans schedule the constraints to ramp over the coming years as sustainability deadlines approach, with the tightest basins front-loaded. Building the measurement habit before the cap arrives is far cheaper than scrambling to reconstruct a water history under audit. A grower who can hand a GSA two seasons of clean, well-by-well extraction records is in a fundamentally stronger position - for compliance, for any future water-trading or transfer market, and for the simple credibility of the operation - than one estimating backward from utility bills.

In other words, the instrumentation you install to save water is the same instrumentation that shows you where that water went, zone by zone. The extraction record stays the well usage you log. The water case and the record are the same investment.

By crop type

Smart irrigation is not one recipe. The demand curve, the sensitivity to stress, and the rooting depth differ by crop, and a good system encodes those differences rather than ignoring them.

Avocado. Avocados are shallow-rooted and notably sensitive to both water stress and salinity. They want frequent, light applications that keep the upper root zone consistently moist without saturating it, and they punish both under- and over-watering quickly. Tight soil-moisture monitoring near the surface matters more here than in deeper-rooted crops, and leaching fractions to manage salts have to be planned in.

Citrus. Citrus is more forgiving and deeper-rooted, but yield and fruit size respond directly to water management through the spring sizing period. The strategy is steadier scheduling tuned to canopy ET, with care around bloom and fruit set, and attention to avoiding waterlogging in heavier Central Valley ground.

Stone fruit and nut orchards. Almonds, walnuts, pistachios, and stone fruit are where regulated deficit irrigation earns its keep: deliberately applying less than full ET during a stress-tolerant window (post-harvest in almonds, the hull-split timing, or the slow-growth phase in stone fruit) to save water with little or no yield penalty. That is a precision move - it only works if you can meter what you apply and watch soil tension closely, which is instrumentation you bring to the orchard yourself.

The crop-specific guides in the library below go deeper on each.

How Persea helps

Irrigation is one face of a platform rather than the whole of it, and that is the part worth understanding before the feature list. The same orchard map that carries your tree inventory carries your irrigation zones; the well usage you record against a well is what your SGMA reporting draws on, with the zone-run records kept separately; the blocks you irrigate are the blocks a harvest lot traces back to. Nothing has to be re-entered between them, because there is no between.

On the irrigation side specifically, here is what runs today. Each zone has its own schedule and its own flow rate, which you can override per zone when a block’s hardware differs from the default. A forecast-rain check records a skip against the schedule, on your farm’s timezone, logging why - the occurrence is dropped before anything opens. Otherwise Persea runs that schedule: it opens the valve at the time you set and closes it on the duration you set, and a schedule you disable or delete while it is watering is closed on the next sweep. Daily reference evapotranspiration and crop coefficients give you the demand picture per block, and a FAO-56 engine plans regulated deficit against it. A daily water balance per zone produces an irrigation decision - Persea’s own, not your schedule’s, and the only one of the two that needs your consent: advisory on every zone, and on zones you have consented Persea acts on it and opens the valve itself. Consent is one affirmation, made under step-up authentication, covering the zones listed to you at that moment; a zone added later stays out until you affirm again; every autonomous run is logged; and you can withdraw at any time, which also stops runs already in flight. Well usage you record rolls up into acre-feet against your groundwater allocation on your water year, separately from the zone-run records. Devices connect through a generic gateway rather than a single vendor’s stack.

And here is what holds that autonomy back on purpose, stated separately so capability and caution are not confused. Reference ET is computed by FAO-56 Penman-Monteith at your orchard’s own coordinates as the primary feed and cross-checked against a second, independent source - the state’s Spatial CIMIS grid where the orchard is in California - with an agreement gate before the system acts. Where the two sources disagree, the balance runs on the lower of the two figures and the engine will not act. Where the second source is silent, that is not agreement either, so the engine reports rather than acts. A wrong irrigation call on a bearing orchard is expensive enough that we would rather hold the valve shut than open it confident.

The honest framing we apply everywhere else applies here too: the tooling earns its keep when the water, energy, and labor it removes exceed what it costs to run, measured per acre on your orchard. If you want to see it against your own blocks, request a demo and we will walk through it with your numbers, including which of the three states on our home page each thing you ask about is in.

Frequently asked questions

What drives the cost of moving to smart irrigation?: Your starting plumbing, far more than the software. If your blocks are already on drip or micro-sprinkler with independently valved zones and known per-zone flow rates, the work is instrumentation and configuration. If the orchard is on flood or on a single shared valve, the real project is zoning it, and that is capital work with a contractor rather than a subscription decision. The honest summary is that the control layer is the cheap part and the pipe is not, so any per-acre figure quoted without seeing your blocks is guesswork.
How long does installation take?: Software onboarding is usually days, not weeks: block boundaries, zones, and a flow rate for each zone. Physical work - latching valves, a gateway with cellular backhaul, and any probes you choose to add - depends on zone count and crew availability, and is commonly staged one block at a time across a season rather than done all at once.
Will it work with my existing irrigation system?: In most cases, yes. Smart scheduling sits on top of standard drip and micro-sprinkler hardware; you do not need to replace emitters or mainline. What Persea needs is that zones can be valved independently, and a flow rate for each zone - which you configure, because Persea does not read a flow meter. Orchards on a single shared valve get less benefit until they are zoned, because there is nothing to differentiate.
How much water can smart irrigation actually save?: Published field studies and grower reports commonly land in the 20-35% range for water applied versus a fixed-calendar baseline, but that band is an average across very different orchards and it is not a figure we have measured ourselves. The real saving on your blocks depends on how over-watered the worst zones currently are. We treat that number as something to measure per zone in acre-feet, not assume from a brochure.
What data do I need to provide to get started?: At minimum: your block boundaries, crop and rootstock, irrigation method, and a flow rate for each zone. Persea multiplies that rate by run time to get applied water, so it is worth setting from your own plumbing rather than leaving it on a default. Weather and reference evapotranspiration come from the weather service against your orchard coordinates, so you do not have to supply those. More history makes the picture better, but you can start with a baseline and let it refine as data accumulates.
Is there a minimum farm size?: No hard minimum, but the economics favor operations large enough that water and labor are real line items - practically, orchards in the tens of acres and up. Below that, the per-zone hardware can still pay off if water is expensive or constrained, but the payback is slower.
How accurate is ET-based scheduling?: ET-based demand estimates are well-validated for tree crops and are the backbone of University of California irrigation guidance. Accuracy improves when ET is corrected by on-site soil-moisture readings, which catch the cases ET models miss: a clogged emitter, a fast-draining sandy patch, or rain that did not reach the root zone. Pairing the two rather than trusting either alone is the right design, and it is the design we are building toward.
Does Persea decide irrigation on ET today?: Yes, and on the zones you have consented it acts on that decision. Today Persea pulls daily reference evapotranspiration, applies crop coefficients, shows you the resulting demand per block and plans regulated deficit on FAO-56. It also runs a daily water balance per zone and decides from it: advisory on every zone, and on consented zones it opens the valve itself. Consent is one affirmation, made under step-up authentication, covering the zones it lists for you at that moment; a zone added later stays out until you affirm again; every autonomous run is logged; and you can withdraw at any time, which also stops runs already in flight. The daily ET0 behind it is cross-checked against a second source: where the two disagree the balance runs on the lower figure and the engine will not act, and where the second source is silent that is not agreement either, so it reports rather than acts. Each zone has its own schedule and its own flow rate, and your schedules run - which is a different mechanism from the decision above, not the same one under another name. Persea opens the valve at the time you set, on your farm's own clock, and closes it on the duration you set; on the schedules you leave weather-aware a forecast-rain check drops the occurrence before anything opens and logs why, and a schedule you disable or delete while it is watering is closed on the next sweep. A schedule running is your own instruction being carried out. The engine acting is Persea's decision, on a zone you consented to, and it is the only one of the two that needs that consent.
Does it integrate with the hardware and software I already use?: Partly, and it is worth being exact about which part. Persea drives valves through an extensible device gateway, so common valve controllers can be brought in over a generic control pathway rather than a single proprietary stack - and that gateway is valve control only: it opens a valve, closes it, and reads its status. Not every valve controller has a driver written for it, and where a direct integration does not exist, manual logging still produces the records and scheduling you need to start.
How does smart irrigation help with SGMA reporting?: Persea keeps two separate records, and which one your GSA report draws on matters. Extraction reporting draws on well usage you record against a well: that is what rolls up into the GSA pack in acre-feet against your allocation. Zone runs are logged separately - start, stop and the water applied - and that water figure is the run time multiplied by the flow rate you configured for the zone, not a meter reading; it does not feed the extraction figures. What the run records give you is the ability to decide where to cut with intent instead of reducing the whole orchard uniformly - and whether your GSA accepts an estimate or wants metered data is theirs to say, so ask them.

Smart irrigation is not a gadget you bolt on for novelty - it is the cheapest way to turn your largest controllable cost into a number you track per zone, in a state that is going to keep asking for that number. Start with one block, meter what you apply, and let the water bill make the argument. The orchards that instrument early will be the ones holding their best blocks when the allocations tighten.

The irrigation guide library

This page is the hub for our irrigation coverage. Each guide below goes deep on one piece. Published guides link straight through; the rest are titles we intend to write, listed as plain text so it is obvious there is nothing behind them yet.

What irrigation really costs per acre in California (not yet written)
SGMA compliance: a grower's field guide
ET-based irrigation scheduling, explained (not yet written)
Choosing soil-moisture sensors for orchards (not yet written)
Avocado irrigation: water needs by growth stage (not yet written)
Citrus irrigation strategy in the Central Valley (not yet written)
Almond and nut orchard irrigation (not yet written)
Regulated deficit irrigation for stone fruit (not yet written)
Drip vs micro-sprinkler for tree crops (not yet written)
Building a per-zone water budget in acre-feet (not yet written)
Drought-year irrigation planning (not yet written)
Retrofitting smart control onto an existing system (not yet written)