Direct injection fertigation · built for commercial protected production
The clipboard was honest work. This is honest record.
Automatic fertilizer and acid dosing that keeps its own continuous feed record, for commercial greenhouses and nurseries.
Feed gets tracked the way it always has: a sheet on the wall, a spreadsheet at the desk, a person in between. The iDoser doses the recipes you set, keeps the record continuously, and keeps it itself.
What it is: a Pearl control direct injection skid.
Plain language first
What direct injection means
The fertilizer never sits in a big batch tank. Concentrated stock solutions stay in their own drums. As irrigation water flows through the line, small precise pumps inject each concentrate directly into the moving water, in proportion to the flow.
The feed is made fresh in the moment it is used. Change the recipe and the next irrigation runs the new one: there is no tank to drain, no batch to remix, and no mixing morning on the calendar.
The concentrates meet the water in the line, already in motion. Illustration.
Where it earns its keep
Built for the crops that punish a feed mistake
Large commercial operations, long rows, thousands of plants on the same line. These are the five places direct injection with a continuous record matters most.
Cannabis and hemp
Multi-room, commercial, licensed. Input logging is expected at every audit. Every injection event is logged with EC, pH, flow and volume, on a timeline nobody had to remember to keep.
Floriculture and ornamentals
Bedding, potted, cut. Uniformity between houses decides finish dates. Two zones can be compared on the same chart, feed by feed, instead of by walking them.
Berries in substrate
Strawberries, raspberries and blueberries in pots and gutters. Substrate berries are unforgiving on pH and EC, and blueberries live in a narrow acid band. Feed pH is read continuously, logged and alarmed.
Container nursery
Long cycles across many zones. Drift hides until the crop shows it. Injector ratios change over time and must be periodically re-verified (University of Georgia Extension, B1237). The chart shows the change when it happens.
Greenhouse vegetables
Tomatoes, peppers, cucumbers, leafy greens on substrate, drain to waste. Heavy feeders, unforgiving of an EC excursion. The excursion is on the chart as it happens, with alarms to email, text or push.
Not on this list
Recirculating hydroponics. NFT, deep water culture and recirculating systems are a different conversation. Ask sales about availability rather than forcing a fit.
The current state of feed tracking
Three places the feed lives today
On the wall today
Feed log · house 2
lunch rush, catch up Monday
At the desk today
| Date | Time | EC | pH | Init |
|---|---|---|---|---|
| 8/28 | 6:05a | 2.1 | 5.9 | JG |
| 8/28 | 9:50a | 2.3 | 5.7 | JG |
| 8/29 | 6:10a | 2.2 | 5.8 | JG |
| 8/30 | wknd? | |||
| 9/01 | 6:00a | 2.4 | 5.6 | TD |
Typed up from the sheet, when there is time to type it up.
The record, keeping itself
Every reading, every event, timestamped as it happens. No initials required.
Between initials
The sheet knows two moments. The crop lives in all of them.
Injector ratios change over time and must be periodically re-verified (University of Georgia Extension, B1237). Drift lives exactly where the sheet is blank.
The same day, kept by the controller: charts of every reading, a log of every event, a CSV when someone asks. Simulated data.
The whole day on one board
See every zone, every feed window, every valve, in one view
Nutrient Alignment lays each irrigation valve against the recipe windows it can draw from, across the whole day. Overlaps are fine: three zones on one header at once is how a large system gets watered. What the board flags is the mismatch, water drawn with no window open, or a window nothing drank.
The Nutrient Alignment board reading a simulated day. The audit is advisory: the grower decides. Simulated data.
Simulated data.
The record follows you
The clipboard stayed on its nail. This comes along.
The same tiles, the same charts and the same log, on the phone already in your pocket. Nothing to transcribe at the end of the day, and nothing waiting on the wall.
checked from the truck, 6:04a
Stock photograph.
When someone asks for the record
An auditor does not want the story. They want the log.
Food safety water documentation, cannabis input logging, a uniformity dispute between houses: the answer is a record nobody had to remember to keep. The schedule says what was supposed to happen. The log says what did. The limits say what was never allowed to happen.
What was supposed to happen: the schedule, with the day drawn as one bar. Simulated data.
What was never allowed: a reading crossed its limit, dosing stopped and stayed stopped. The console's own words: the limits armed and tripped, and nothing restarts injection but a human. Simulated data.
Stated exactly
EC and pH lockout thresholds can be configured to lock out injection and stop the pump on an out-of-range reading.
Three ways in
Start with the record. Add control when you are ready.
Pearl Protect
Monitor only, by design. It reads the skid you already own and never writes to it. The record, the charts and the alarms.
Ships todayPearl Digital
Adds remote control: see EC and pH, change the feed rate, enable or disable feedback dosing, shut dosing down.
Full system
Pearl plus a new direct injection skid, quoted per job for your zones, channels and water.
On price: sales quotes each system for the operation in front of them, and payback is worked in months from your own numbers, your flow, your feed, your labor, and the crop you are protecting. Agricultural wages have risen roughly 35% since 2019 (Farm Credit East, 2026 Green Industry Outlook); the hours are the expensive part. Estimate your own payback below.
See what it is worth on your crop
Your numbers, not our brochure
Pick where you are starting. The estimate runs on typical numbers for a commercial grow, and you can open any line to see and change what drives it. It is an estimate, not a guarantee.
Tap any line to see and change what drives it.
An estimate from typical numbers, not a guarantee of results. Open any line to put your own figures in. Bring these to sales and they will work it against a real quote.
Parameter
Backed by Link4
You are not buying a black box from a stranger
- Over 20 years of Link4 greenhouse control behind the platform, and injection hardware that has been in operations since 1955.
- A hardware warranty on every system. Ask sales for the current coverage on your configuration.
- Onsite commissioning available: a Link4 person sets it up on your skid and walks your team through it.
- A real phone number and people who know the product. Support is support@link4controls.com.
Asked out loud
The questions growers actually ask
What happens if a reading goes out of range?
EC and pH lockout thresholds can be configured to lock out injection and stop the pump on an out-of-range reading. Dosing stays stopped until a person restarts it, and the alarm reaches you by email, text or push.
Does it work with the injection skid I already own?
If you run an Anderson-class skid with a Modbus interface and no other control system on that connection, Pearl Protect reads it without changing how the skid runs. That first question, whether another controller already sits on the skid, is the first thing sales will ask you.
What if I never want it to dose on its own?
Then it never does. Pearl Protect is monitor only by design: it cannot write to the skid. You get the record, the charts and the alarms, and dosing stays exactly as it is today.
Is there a subscription?
Yes. The system includes a Link4 Cloud subscription for the remote view, the continuous record and the alarms, quoted with your system so there is no surprise on the invoice later.
How often do the probes need calibration?
EC and pH probes need periodic calibration, like any such instrument on any fertigation system. Your team can do it, or a Link4 calibration visit can, and the console alarms on an out-of-range reading in between.
Who is behind this?
Link4 Controls, building greenhouse control systems for over 20 years. The injection hardware is built by H.E. Anderson making injection systems since 1955. Pearl reads the skid over Modbus using a register map the manufacturer supplied.
Try it before you talk to anyone
Run the actual console for 30 minutes. Free.
DryRun is the iDoser console over a simulated injection skid: the dashboard, the schedule, the recipes, the valves and the alarms, running a full simulated day. No hardware, no install, nothing to undo.
- Drive the same screens a grower uses in production
- Watch EC and pH move as recipes dose a simulated day
- Trip a lockout on purpose and see what stops
- Simulated data only: nothing you do touches a real crop
Your session runs 30 minutes once the console loads. When it ends, a Link4 person picks it up from there: bring your questions.
Console not loading? Open DryRun in a new tab. Your 30 minutes runs either way.
Your DryRun session has ended.
Thirty minutes goes fast when the charts are moving. The next step is a conversation: what you grow, what your water is, and what your skid looks like. A Link4 person will already have your note.
Prefer email? sales@link4controls.com
Before you decide anything
Fifty-eight seconds of the actual console.
The dashboard, the log, the schedule, the recipes, the valves and the alarms, exactly as they look on screen.
the sheet can retire with honor