Sulfur Deficiency in Plants: Signs, Causes and How to Fix It
Sulfur deficiency in plants starts on the young leaves and the growing tip. Sulfur is part of the amino acids cysteine and methionine, so plants need it to build proteins. It helps make chlorophyll and helps legumes form their root nodules. It is also part of the enzyme that turns nitrate into protein. So a crop short of sulfur cannot use its nitrogen well. Here are the signs in each crop, what brings it, how to be sure and the fertilizer that fixes it.
Sulfur moves only slowly out of old leaves, so most crops show the pale color first on the young, upper leaves. A few crops, such as citrus, show it on old leaves first, and a bad shortage turns the whole plant pale.
Sulfur deficiency symptoms
Young leaves turn evenly pale green to yellow, veins included, and in bad cases the whole plant looks washed out. Plants stay short and thin with stiff, woody stems, and they ripen late. Rice makes fewer tillers and shorter panicles, and yellow seedlings in the seedbed die in large numbers after transplanting. In corn the upper leaves can show pale stripes between darker veins.
Sulfur deficiency by crop
Each crop shows it its own way. So find yours in the tables below, then open its page for the photo and the full fix, like the one for sulfur in rice.
Rice
| Crop | The first sign | Fix with |
|---|---|---|
| Palay | The whole plant is pale yellow, and the youngest leaves are the palest. | Ammonium sulfate 21 0 0, Complete 14 14 14 with sulfur (14 14 14 12S) |
Corn and Sorghum
| Crop | The first sign | Fix with |
|---|---|---|
| Mais | The young upper leaves are the palest, while the lower leaves stay greener. | Ammonium sulfate 21 0 0, Gypsum |
| Batad | The young upper leaves turn evenly pale yellow, with no dead spots. | Ammonium sulfate 21 0 0, Gypsum |
Legumes
| Crop | The first sign | Fix with |
|---|---|---|
| Monggo | The young leaves turn pale yellow first, then the whole plant is evenly pale. | Gypsum, Ammonium sulfate 21 0 0 |
| Mani | The whole plant is evenly light green, thin stemmed and spindly. | Gypsum |
| Utaw | The newest leaves turn pale first, then the whole plant is evenly yellow green. | Gypsum |
| Kadyos | New leaves yellow first, then the whole plant is evenly yellowish. | Gypsum |
Root Crops
| Crop | The first sign | Fix with |
|---|---|---|
| Kamote | Leaves yellow from the tip to the base, veins included, and vines stay short with few branches. | Ammonium sulfate 21 0 0, Single superphosphate 0 20 0 |
| Kamoteng kahoy | The young upper leaves yellow first, and stems are thin and weak. | Ammonium sulfate 21 0 0, Gypsum |
| Gabi | Younger leaves are small and evenly yellow, and roots stay short. | Ammonium sulfate 21 0 0, Gypsum |
| Patatas | The whole plant, young leaves included, yellows evenly, with reddish veins and leaf stalks. | Ammonium sulfate 21 0 0, Single superphosphate 0 20 0 |
| Luyang dilaw | Stunted plants whose leaves turn pale yellow, veins included. | Epsom salt / magnesium sulfate, Ammonium sulfate 21 0 0 |
Vegetables
| Crop | The first sign | Fix with |
|---|---|---|
| Petsay | Young centre leaves turn pale with blue green veins and purple undersides. | Ammonium sulfate 21 0 0, Gypsum |
| Repolyo | Young inner leaves turn pale yellow and the plant is slow to head. | Ammonium sulfate 21 0 0, Gypsum |
| Mustasa | Young leaves turn pale between blue green veins, cup, and get purple undersides. | Ammonium sulfate 21 0 0, Gypsum |
| Brokoli | Young leaves turn pale, stiff and purplish, with narrow spoon shaped leaves on long stalks. | Ammonium sulfate 21 0 0, Gypsum |
| Koliplor | Young leaves turn evenly pale, stiff and reddish, with thin leaf stalks. | Ammonium sulfate 21 0 0, Gypsum |
| Kamatis | Young top leaves turn pale yellow green, stiff and curled down, with purple stems. | Ammonium sulfate 21 0 0, Gypsum |
| Talong | Young leaves turn evenly yellow, stay narrow and pointed, and veins look reddish. | Ammonium sulfate 21 0 0, Gypsum |
| Sili | Young top leaves turn evenly pale and curl down, with reddish veins. | Ammonium sulfate 21 0 0, Gypsum |
| Atsal | The youngest top leaves look evenly pale from a distance, with short jointed stems. | Ammonium sulfate 21 0 0, Sulfate of potash 0 0 50 |
Onion and Garlic
| Crop | The first sign | Fix with |
|---|---|---|
| Sibuyas | Young leaves turn evenly yellow, plants are thin and spindly, and bulbing is late. | Ammonium sulfate 21 0 0, Single superphosphate 0 20 0 |
| Sibuyas na mura | Young leaves are evenly pale yellow and the plants thin and weak. | Ammonium sulfate 21 0 0, Gypsum |
| Bawang | Young leaves turn evenly yellow, plants are thin and weak, and bulbs are light with weak flavour. | Ammonium sulfate 21 0 0, Gypsum |
| Sibuyas Tagalog | Young leaves turn evenly yellow, plants are thin, and bulbs are light and mild. | Ammonium sulfate 21 0 0, Single superphosphate 0 20 0 |
Sugarcane and Industrial Crops
| Crop | The first sign | Fix with |
|---|---|---|
| Tubo | The top young leaves turn yellow green with purple edges, while the old leaves stay greener. | Ammonium sulfate 21 0 0, Gypsum |
| Tabako | The bud and the top leaves pale first, and the whole plant slowly turns light green from the top down. | Ammonium sulfate 21 0 0, Sulfate of potash 0 0 50 |
| Bulak | The young top leaves turn pale green to yellow while the old leaves stay green. Plants are small and spindly. | Ammonium sulfate 21 0 0, Superphosphate 0 20 0 |
Fruits and Plantation Crops
| Crop | The first sign | Fix with |
|---|---|---|
| Saging | Young leaves even pale yellow, veins included, on a small slow plant. | Ammonium sulfate 21 0 0, 16 20 0 |
| Niyog | Fronds pale yellow to orange, fewer nuts, and copra that comes out rubbery and shrunken. | Ammonium sulfate 21 0 0, Gypsum |
| Kape | Young leaves pale yellow, a little more along the midrib, but they keep their shine. | Ammonium sulfate 21 0 0, Gypsum |
| Kakaw | The newest mature leaves evenly yellow green on a very short last flush. | Ammonium sulfate 21 0 0, Gypsum |
What causes sulfur deficiency
Sulfate washes out of sandy soils low in organic matter, the more so with heavy rain soon after planting. Highly weathered red soils rich in iron oxides, allophane volcanic soils and fields where straw is burned or hauled away also run short. Fields fed only urea and muriate of potash get no sulfur at all, because neither fertilizer contains it. Surveys also found sulfur short in some coconut areas.
How to be sure it is sulfur
Sulfur shortage looks almost the same as nitrogen shortage. The clue is where it starts: sulfur paleness shows on the young leaves first, while nitrogen yellows the old leaves first. Soil tests for sulfur help but are less exact than tests for phosphorus or potassium. So a leaf tissue test is the surer check. In lowland rice, the MOET pots show if sulfur is the missing nutrient.
How to fix sulfur deficiency
Ammonium sulfate (21 0 0) is the usual fix. Gypsum, superphosphate (0 20 0), sulfate of potash and Epsom salt also supply sulfate. Elemental sulfur works only after soil bacteria turn it into sulfate, so it is slow. A typical field crop rate is 11 kg of sulfur per hectare, near one bag of ammonium sulfate, but the soil test decides.
Fertilizers sold here that supply sulfur
| Product | Made or sold by | What it holds | Use |
|---|---|---|---|
| Atlas Ammosul 21 0 0 | Atlas Fertilizer | 21 0 0 with 24 percent sulfur | On the soil |
| Philphos Gypsum | Philphos | 22.2 percent calcium and 17.4 percent sulfur | On the soil |
| Harvester Sulphate of Potash | Universal Harvester | 0 0 50 with 17.5 percent sulfur | On the soil |
| Agsmart Kieserite Granule | AgSmart | 20 percent sulfur and 16.3 percent magnesium | On the soil |
| VSI Sulfur Powder | Newman Chemicals | 99.5 percent sulfur | On the soil |
| Amigo Planters Granular Single Super Phosphate | La Filipina | 0 18 0 with 11 percent sulfur | On the soil |
| Magnesium Sulfate Heptahydrate | Zetryl Chem | 13 percent sulfur and 9.5 percent magnesium | Soil or leaves |
| Amigo Planters Ammonium Phosphate | La Filipina | 16 20 0 with 13 percent sulfur | On the soil |
For rates and timing, see our guides to ammonium sulfate fertilizer and to fertilizer application methods. Also, anee.io keeps every application on the cropping calendar, so you know what went on each lot and when.
How to keep sulfur deficiency away
Use ammonium sulfate or another sulfur carrying fertilizer in the basal dose, and plow straw back in instead of burning it. In rice, dry tillage after harvest and good drainage between crops keep more sulfur in a form roots can take.
In flooded fields rich in organic matter, heavy sulfate can turn into hydrogen sulfide, which blackens rice roots. The young leaves then turn yellow between the veins, much like iron shortage.
Pick your crop in the Nutrient Deficiency Finder, say where the leaves changed first and what you see, and get the fertilizers sold here that fix it.
- Anee, the smart farm technician, reads a photo of the leaf in Tagalog or English
Sulfur deficiency questions
What does sulfur deficiency look like?
What is the best fertilizer for sulfur deficiency?
Does urea contain sulfur?
How much ammonium sulfate should I give a coconut tree?
Find the missing nutrient and fix it
With Libre + Anee, read the whole guide: how to tell the deficiency from look alikes, how to be sure, what to apply, and the fertilizers sold here that supply it.
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