27 · IrrigationADVANCED
Crop steering
The pro irrigation mode. Instead of "water when it drops below X", it splits the day into phases and uses dryback — how much the substrate dries down — as the lever to push the plant toward vegetative growth or toward dense flower.
The phases of the day
- P1 · Ramp-up
- It starts a few minutes after the light comes on and brings the substrate to field capacity, with short shots and pauses to measure.
- P2 · Maintenance
- During the day, it holds a moisture floor with smaller shots.
- P3 · Cutoff
- It stops watering however many minutes you choose before the light goes off, so the substrate dries down overnight.
- Night
- No watering. The overnight dryback is the goal, not a problem.
Vegetative or generative
| Mode | Ideal dryback | What it produces |
|---|---|---|
| Vegetative | 10 – 20 % | Small, steady drybacks. Pushes growth and stretch. |
| Generative | 15 – 25 % | Bigger drybacks, especially overnight. Pushes denser flower. |
| Automatic | — | Follows the zone's stage. |
Per-phase values you'll run into
| Setting | Vegetative | Generative |
|---|---|---|
| P1 starts (min after lights on) | 30 | 60 |
| P1 moisture target | 65 % | 62 % |
| P1 shot / pause / maximum | 30 s · 15 min · 12 | 30 s · 20 min · 10 |
| P2 moisture floor | 58 % | 54 % |
| P2 shot / pause / maximum | 20 s · 45 min · 8 | 20 s · 60 min · 6 |
| P3 cutoff (min before lights off) | 90 | 120 |
| P3 overnight dryback target | 6 % | 10 % |
Shadow: try it without watering
- Crop steering starts in shadow mode: it calculates and logs what it *would have* watered, without opening a valve.
- To switch to real watering it asks for three complete light cycles logged, the zone qualifying, and the targets loaded. Until they're there, the button won't let you tap it and tells you why.
- With autopilot on, it makes the switch by itself as soon as those conditions are met, notes it in the feed, and goes back to shadow on its own if things turn ugly.
- Several safety cutoffs in the same day drop the zone to shadow. Cutoffs less than 30 minutes apart count as a single incident: one odd spike from the probe won't drop your zone.
The brakes
| Brake | What it does |
|---|---|
| Survival floor | Below that percentage it waters anyway, whatever the hour. It's the only exception to the phases. |
| Moisture ceiling | It never waters above that value. |
| Maximum shots and minutes per day | Hard caps, no matter what. |
| Adaptive P3 cutoff | Optional: instead of a fixed cutoff, the system stretches or shortens it based on how fast your zone dries, using the median of the last seven days. One odd day can't double or halve the cutoff all at once. |
Do this
Leave it in shadow for a full cycle and read what it says it would have done. It's the cheap way to find out the probe is in the wrong spot.
Avoid this
Don't start your first grow in generative. A 25 % dryback with the probe badly placed is a week of stress you won't be able to undo.
How urgent it is
EssentialNothing: wet/dry is enough for most people.
ImportantShadow mode, to see what it would do.
OptionalReal mode with autopilot and adaptive P3.