悟る · diagnose & fix
Cannabis Nitrogen Deficiency
Nutrient deficiency · also: yellowing leaves, N deficiency, yellow fan leaves
Older, lower leaves yellow and fade from the bottom up — the classic sign a cannabis plant is short on nitrogen.
Not sure it's nitrogen deficiency?
Snap a photo and get a free read — no signup. Satoru weighs the visual against the conditions that cause look-alikes, so you treat the real problem.
What it looks like
Yellowing starts on the OLDEST (lowest) leaves and climbs upward. The whole leaf pales to a uniform light green, then yellow, before drying and dropping. Nitrogen is mobile, so the plant pulls it from old growth to feed new tips.
Symptoms
- Lower/older leaves yellow first, evenly across the leaf
- Yellowing climbs up the plant over time
- Pale, slow new growth
- Lower leaves curl, dry, and drop
Causes
- Underfeeding / nutrient solution too weak
- Late veg with depleted soil
- pH out of range locking out nitrogen
- Over-watering suffocating roots so they can't uptake N
How to fix it
- 1Confirm root-zone pH is in range (soil 6.0–7.0, hydro/coco 5.5–6.5) BEFORE adding nutrients
- 2Feed a balanced grow nutrient with adequate nitrogen at label strength for the stage
- 3In late flower, mild lower-leaf yellowing is NORMAL fade — don't chase it
- 4Recheck in 3–5 days; new growth greening up confirms the fix
Prevention
- Feed to the stage — veg wants more N than flower
- Keep pH in range so the N you feed is actually available
- Don't over-water; healthy roots uptake nutrients
悟る · how satoru tells it apart
Bottom-up even yellowing reads as nitrogen — but pH lockout and over-watering mimic it. Satoru weighs your logged pH, feed, and watering against the photo so you treat the real cause, not just the color.
Commonly confused with: Nitrogen Toxicity, pH Lockout, Overwatering.
Not sure it's nitrogen deficiency?
Snap a photo and get a free read — no signup. Satoru weighs the visual against the conditions that cause look-alikes, so you treat the real problem.
More plant problems
Educational reference for cultivation troubleshooting. Symptoms overlap — when in doubt, match against your own conditions. Satoru fuses your photo with your logged environment for a grounded read.