悟る · diagnose & fix
Cannabis Iron Deficiency
Nutrient deficiency · also: Fe deficiency, bright yellow new leaves, interveinal chlorosis new growth
Bright yellow NEW growth with green veins — iron is immobile, so the youngest leaves show it first.
Not sure it's iron 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
The newest top leaves turn bright, almost neon yellow between the veins while the veins themselves stay green (interveinal chlorosis). Because iron doesn't move within the plant, the damage is on the TOP/new growth — the opposite of nitrogen, which hits the bottom first.
Symptoms
- Bright yellow new/top leaves with green veins
- Older leaves stay normal green
- Starts at the growing tips
- Often triggered right after a pH swing
Causes
- Root-zone pH too high, locking out iron (most common cause)
- Overwatering / cold roots slowing uptake
- Excess phosphorus tying up iron
- Genuinely iron-poor solution (rare)
How to fix it
- 1Check and correct pH FIRST (hydro/coco 5.5–6.5, soil 6.0–7.0) — most 'iron deficiency' is really lockout
- 2If pH is right, feed a cal-mag or micronutrient with chelated iron
- 3Warm and aerate a cold/soggy root zone
- 4New growth greening confirms it in 3–5 days
Prevention
- Hold pH in range so micronutrients stay available
- Don't overdo phosphorus bloom boosters
- Keep roots warm and oxygenated
悟る · how satoru tells it apart
Top-down yellowing points to iron, but it's usually a pH lockout, not an empty tank — and it's easy to confuse with cal-mag. Satoru weighs your logged pH so you fix the cause instead of dumping more iron into a locked root zone.
Commonly confused with: Calcium & Magnesium (Cal-Mag) Deficiency, pH Lockout, Nitrogen Deficiency.
Not sure it's iron 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.