Visual reference slot
Needed asset: Photosynthesis Flow Card showing light input, CO2 entry, water movement, sugar production, oxygen release, and stress limits.
Field checklist
- Check leaf color, posture, surface temperature, and light-zone location.
- Separate lower-light fade from upper-canopy light stress.
- Compare new growth to older shaded growth.
Measurements to pair
- PPFD, DLI, photoperiod, fixture distance.
- Temperature, RH, VPD, CO2 context.
- Water status and root-zone oxygen.
Common mistakes
- Assuming more PPFD always improves growth.
- Ignoring VPD and water movement when raising light.
- Diagnosing light stress from color alone.
Grow Doc prompt
Evaluate whether leaf symptoms may be tied to photosynthesis limits: PPFD, DLI, photoperiod, canopy position, leaf temperature, VPD, water status, and new-growth response.