Iron: new leaves yellow, veins still green
Often a pH lock, not a missing bag of iron.
- Sort which leaves are yellow.
- New leaves yellow with green veins, worst at the tip.
- Old leaves stay greener.
- Nitrogen yellows old leaves. Iron yellows new leaves with green veins.
- Manganese often adds brown specks. Iron is a cleaner interveinal yellow.
- New leaves yellow with green veins, worst at the tip. Old leaves stay greener.
- Don’t chase yellow with urea.
- Foliar chelated iron (first aid): Labelled lower rate, repeat a few times on new leaves. A small patch first. Broadcasting ferrous sulphate on high-pH land as a cure usually floats away
- New yellow leaves with green veins: think iron, not nitrogen.
- On high pH, ferrous sulphate often fails this season.
What you see in the field
Decide whether the yellow leaves are new or old. New leaves yellow with veins still green, worse at the tip, while old leaves stay greener: that looks like iron shortage or iron locked by pH. Hold a new leaf to the light. Calcareous soil, alkaline irrigation and a high pH stop iron moving. Do not spray foliar iron at the first yellow; ask pH first.
Tap to enlarge. The caption says what to photograph. Missing field photos are marked as to-be-added.
Why it looks like this
Iron barely moves from old leaves, so shortage yellows new leaves with veins still green. At high pH iron is locked in the soil — the bag is not empty. Calcareous parent material, extra lime and alkaline irrigation all lock new leaves yellow. Test pH before a foliar spray. Liming grain land and spraying iron are different jobs.
A sketch. Do not fertilise from the picture alone.Easy to mix up
Looks like “Nitrogen on old leaves”
Nitrogen yellows old leaves evenly. Iron yellows new leaves with green veins. Mix the position and the fertiliser goes the wrong way.
Looks like “Manganese interveinal yellow”
Manganese can also start on new leaves; the lab separates them. Read new versus old first, then sample. Do not pour two micronutrients at once.
Do this / don’t do that
- 1Read new versus old leaves. New leaves yellow with veins still green: then iron lock is on the table. Wrong position: do not spray foliar iron.
- 2Test plough-layer pH. When it is high, iron is often locked, not missing. On calcareous soil, ask whether the irrigation water is alkaline too.
- 3Foliar iron is first aid. The lasting job is pH and irrigation. Rates follow the label and a local station. This page does not print a bag count.
Don’t do this first
- Do not spray foliar iron at the first yellow.
- Do not add lime when pH is already high.
- Do not mix tea and grain pH windows.
Rate range
| Crop × texture | Texture | Rate | Note |
|---|---|---|---|
| Fruit / peanut / soybean | Calcareous | Foliar chelated iron at the labelled lower rate, repeat on the new flush | Small patch first. Root zone: organic matter and steady moisture |
These are ranges. Confirm with your local extension station and the product label.
| Cell | Low | Mid | High |
|---|---|---|---|
| pH | Iron more available | Crop-dependent | Iron locks |
| Available Fe | May be short | Still read pH | On high pH the root may still miss it |
One number example
Yellow new leaves with green veins and a high plough-layer pH: stop extra lime. Foliar iron is first aid. The lasting question is pH and irrigation water. Tea and grain do not share a pH window.
Pinch a new leaf. Sample the root zone, not the footpath between rows.
Lesson video
2026-04-19 · Li Zeyu · For learning. Serious damage: local agronomist or a soil test.
For learning only. Fertiliser and pesticide decisions need a local agronomist and a soil test.
Not sure? Photograph the field to identify the problem