Nutrient Deficiency Chart: Leaf Symptoms by Deficiency

A nutrient deficiency chart tells you which leaf to look at before it tells you what is wrong. Yellowing at the bottom of the plant and yellowing at the growing tip mean almost opposite things: one says the plant moved an element out of old tissue to feed new tissue, the other says the element could not get into the new tissue at all. Read the chart in that order (where the symptom starts, then what it looks like) and you narrow twelve possible deficiencies down to two or three before you touch a bag of fertiliser.

Visual diagnosis is a starting position, not a verdict. Drought, salt burn, herbicide drift and root disease all produce yellow leaves, and treating a pH problem with fertiliser wastes the money and delays the fix. This guide gives the chart, the reasoning behind it, the common lookalikes, and the test to run before you act.

The rule that lets you read any deficiency chart

Plants can move some elements from old tissue to new tissue when supply runs short, and cannot move others. Those are the mobile and immobile nutrients, and mobility decides where the first symptom appears. Deficiency symptoms of mobile nutrients will appear first in older parts of the plant, while symptoms for immobile nutrients will be seen first in new growth.

In practice: deficiency symptoms for mobile nutrients in plants like nitrogen, phosphorus, potassium and magnesium are first expressed in older leaves. Calcium, iron, manganese, zinc, boron and copper are immobile, so their symptoms show on the youngest leaves and the growing points, where the plant cannot cannibalise a substitute. Sulfur behaves like an immobile nutrient, showing up on young leaves first, which is what separates it from nitrogen in the field.

Nutrient deficiency chart

Nutrient	Mobility	Starts on	What you see	Confirm with
Nitrogen (N)	Mobile	Old, lower leaves	Uniform pale green to yellow, whole plant stunted, oldest leaves yellow then brown	Soil test N or tissue test
Phosphorus (P)	Mobile	Old, lower leaves	Dark green with purple or reddish tint on leaves and stems, short spindly growth	Soil test P; check pH first
Potassium (K)	Mobile	Old leaf margins	Marginal scorch, brown edges rolling inward, weak stalks	Soil test K
Magnesium (Mg)	Mobile	Old leaves	Interveinal chlorosis with a green arrowhead along the midrib	Soil test Ca:Mg ratio
Sulfur (S)	Immobile	Young, upper leaves	Uniform pale yellow, no spots, whole plant pale	Tissue test; soil S
Calcium (Ca)	Immobile	New leaves, tips, fruit	Distorted new growth, hooked tips, blossom-end rot	Soil pH and irrigation
Iron (Fe)	Immobile	Newest leaves	Interveinal chlorosis, veins stay dark green	Soil pH: usually too high
Manganese (Mn)	Immobile	New leaves	Interveinal chlorosis with mottling and small dead spots	Soil pH and tissue test
Zinc (Zn)	Immobile	New leaves	Small leaves, short internodes, rosetted shoots, striping	Tissue test
Boron (B)	Immobile	Growing points	Terminal bud dies, brittle hollow stems, deformed fruit	Tissue test
Copper (Cu)	Immobile	New leaves	Pale tips, wilting of new growth, dieback	Tissue test
Molybdenum (Mo)	Immobile	Old then middle leaves	Cupped, scraggly leaf development	Soil pH: usually too low

Macronutrient symptoms in detail

Nitrogen is the most common deficiency and the easiest to misread, because uniform yellowing also happens when a plant is waterlogged. The tell is position: nitrogen shows on the oldest leaves first and moves up, and in cereals the yellowing runs back from the leaf tip in a V shape. Legumes that started slowly and never developed nodules show it too, even on ground that tests adequate.

Phosphorus produces dark green leaves with a purple or red cast, most visible on stems and leaf undersides in cool spring weather. Purple colour alone is not a diagnosis: cold soil blocks uptake even when the test is fine, and the colour fades as roots catch up.

Potassium burns from the edge inward. Margins go chlorotic then necrotic, spots cluster along the edge, and stalks lodge. Because potassium is mobile, the damage starts on the older leaves while the growing point stays green.

Magnesium is the classic interveinal chlorosis with a difference: the veins and midrib stay green in an arrowhead or Christmas-tree pattern on the oldest leaves. It shows up in sandy soils and in pots that have been leached for a season.

Sulfur looks like nitrogen on the wrong leaves. Sulfur deficiency shows as young leaves that are pale green or light yellow without any spots, and the symptoms resemble those of nitrogen deficiency. Young leaves first is the whole difference, and it is why a tissue test is worth the fee before you spread elemental sulfur.

Calcium does not move at all, so the damage is structural: distorted new leaves, hooked tips, growing points that stall, and blossom-end rot in fruit that is not calcium-hungry so much as irregularly watered. Soil pH and irrigation consistency decide calcium uptake more than the amount in the soil.

Micronutrient symptoms in detail

Iron is the one growers meet most often, because it is pH-controlled rather than quantity-controlled. Iron deficiency is common early in the year and in basic (high pH) soils. The pattern is sharp: newest leaves go yellow between the veins while the veins stay dark green, with no brown spotting. Raising the pH of an alkaline soil, or chelating the iron, fixes it; broadcasting more iron sulfate does not.

Manganese mimics iron but messier, with mottling and small necrotic spots inside the yellow area, and it appears on slightly acid to alkaline soils too. Zinc shows as small leaves, shortened internodes and rosetted shoots, common in fruit trees and corn on high pH ground. Boron kills the terminal bud first, which is unmistakable once you have seen it. Copper wilts and pales the newest growth. Molybdenum is the exception that runs backwards: it is less available in acid soil, so a pH that is too low can induce it.

What it is not: the lookalikes

Deficiencies tend to form symmetrical patterns, where both sides of the leaf or plant part show the same pattern. Disease and spray damage are usually lopsided or scattered, and they follow the lesion rather than the vein. Beyond that:

• Salt or fertiliser burn browns leaf margins with a yellow halo, separated from green tissue, starting wherever the granules landed.
• Drought wilts uniformly and picks up from the growing point once water returns; it does not leave a clean interveinal pattern.
• Herbicide damage distorts growth in ways no deficiency does: cupped, strapped, fern-like or swollen tissue with no chlorosis that follows the veins.
• Root disease and compaction yellow the whole plant at once, because the entire root system is compromised rather than one element.

Confirm before you treat

Three checks, in this order. First, read the position of the symptom and narrow the chart to one or two candidates. Second, test the soil, pH especially, because a pH outside the availability window makes an adequate soil look deficient and no amount of fertiliser will fix it. Third, if the candidate still looks likely, run a plant tissue test: it measures what actually got into the plant, which is the question a soil test cannot answer. Where the two disagree, the CEC calculator shows how much the soil can hold and release in the first place, and what a lab analysis adds that a home kit cannot explains why the paid test is the one worth acting on.

Keep the sample honest while you do it. Take several plants from the affected area and several from healthy ground nearby, wash off dust, and send the tissue in a paper bag rather than plastic, because a sample that rots in transit tells you nothing. If more than one nutrient is short at the same time, or the plant is also under water or pest pressure, the visual pattern will be misleading and the lab numbers are the only thing worth acting on.

Work the target band from the soil pH by crop reference table or from a species record in the plant pH database, and pick the tool with the right test for the job. Where the fix is a foliar or a sulfate, iron sulfate and elemental vs sulfate sulphur cover the difference between correcting pH and feeding the plant.

Sources

• Identifying Nutrient Deficiencies in Ornamental Plants, University of Delaware Cooperative Extension; backs Deficiency symptoms of mobile nutrients will appear first in older parts of the plant, while symptoms for immobile nutrients will be seen first in new growth..
• Diagnosing Nutrient Deficiencies, University of Missouri Integrated Pest Management; backs deficiency symptoms for mobile nutrients in plants like nitrogen, phosphorus, potassium and magnesium are first expressed in older leaves..
• Plant Nutrient Deficiency Symptoms, Montana State University Extension; backs Iron deficiency is common early in the year and in basic (high pH) soils..
• Nutrient Deficiencies in Plants, West Virginia University Extension; backs Sulfur deficiency shows as young leaves that are pale green or light yellow without any spots, and the symptoms resemble those of nitrogen deficiency..
• Guide to Symptoms of Plant Nutrient Deficiencies, University of Arizona Cooperative Extension; backs Deficiencies tend to form symmetrical patterns, where both sides of the leaf or plant part show the same pattern..