Coffee Nutrient Deficiency: Signs, Causes and the Fertilizer That Fixes It
Coffee nutrient deficiency is one of the first things to check when the leaves of your kape (coffee) turn yellow, purple or burnt at the edges. On Philippine farms the usual ones are nitrogen, phosphorus, potassium, boron, zinc, magnesium, calcium, sulfur and iron. This guide shows where each one starts, how to be sure, and the fertilizer that fixes it.
Start with one question: did the change begin on the old leaves or on the young ones? Nitrogen, phosphorus, potassium and magnesium move inside the plant, so a shortage shows on the old, lower leaves first. But boron, zinc, calcium, sulfur and iron stay where the plant first put them, so the young leaves and the growing tip show it first. After that, the color and the pattern narrow down which coffee nutrient deficiency you have, and a soil test confirms it. Each one below has its signs, its causes and its fix.
Coffee nutrient deficiency signs, old leaves and young leaves
Shows first on the old leaves
| Nutrient | Where it starts | What you see | Fix with |
|---|---|---|---|
| Nitrogen | the whole plant, old, lower leaves | The whole tree turns pale yellow green, leaves lose their shine and new shoots barely grow. | Urea 46 0 0, Ammonium sulfate 21 0 0 |
| Phosphorus | old, lower leaves, the roots | Old leaves go mottled yellow or take a pink to purple tint. Roots and new growth stay weak. | Ammonium phosphate 18 46 0, 16 20 0 |
| Potassium | old, lower leaves, leaf edges and tips | Old leaves get a yellow band at the edge, then dark brown dead spots that join into a burnt edge. The centre stays green. | Muriate of potash 0 0 60, Sulfate of potash 0 0 50 |
| Magnesium | old, lower leaves, between the veins | Old leaves yellow along the edges and between the veins, with a wide band of sunken light brown spots. | Magnesium sulfate (Epsom salt), Kieserite |
Shows first on the young leaves
| Nutrient | Where it starts | What you see | Fix with |
|---|---|---|---|
| Boron | young leaves and the tip, fruit, grain or tubers | New leaves come out small, bent and misshapen with dead tips, and the shoot tip dies. | Borax, Solubor |
| Zinc | young leaves and the tip, between the veins | New leaves narrow and strap like, yellow between dark green veins, bunched at the branch tip. | Zinc sulfate, Agricultural lime |
| Calcium | young leaves and the tip, leaf edges and tips | Young leaves turn bronze at the edges and cup downward. The shoot tip dies back. | Agricultural lime, Dolomite |
| Sulfur | young leaves and the tip, the whole plant | Young leaves pale yellow, a little more along the midrib, but they keep their shine. | Ammonium sulfate 21 0 0, Gypsum |
| Iron | young leaves and the tip, between the veins | Young leaves light yellow to creamy white with a sharp net of green veins. Old leaves stay green. | Ferrous sulfate |
Before you buy fertilizer for a coffee nutrient deficiency
So use the table to pick the likeliest coffee nutrient deficiency, then read its section below. Also keep in mind that dry soil, standing water, cold nights, a pest or a disease can look the same. That is why it pays to check the roots and the whole field first.
Nitrogen deficiency in coffee
Leaves turn an even pale green, then yellow green, until the whole tree looks pale. In full sun the young leaves may pale first, with the old leaves following. Other times the older, lower leaves go first. Leaves lose their normal glossy shine, old leaves may show whitish veins and drop early. Shoot growth falls by half or more. Flowering comes late and beans fill poorly. You see it most at this stage: any age, worst during new leaf growth and flowering, when uptake peaks, and on heavy bearing trees.
Why nitrogen deficiency happens in kape
Trees that get little or no fertilizer, sandy or eroded soils with little organic matter, heavy rain that washes nitrogen down. Coffee grown in full sun, which uses nitrogen fast.
How to tell it apart
Sulfur deficiency also yellows young leaves, but those leaves keep their shine and the yellow sits along the midrib. Coffee leaf rust gives round pale yellow spots on top of the leaf with orange powder underneath, starting on the lower branches, not an even pale color. To be sure, send a leaf sample from at least 15 trees, at or just before flowering. On a side branch halfway up each tree, take the newest mature leaf, usually the third or fourth pair from the tip. Healthy leaves test 3.0 to 3.7 percent nitrogen.
What to apply for nitrogen deficiency
Apply Urea 46 0 0 or Ammonium sulfate 21 0 0 in a ring under the canopy and work it in, following the soil test. For a quick boost, give a foliar spray of Urea at 10 grams per liter (160 grams in a 16 liter sprayer) every 15 days. Mature coffee takes up 150 to 250 kg of nitrogen per hectare each year. So split the soil dose over the rainy season.
- Urea 46 0 0
- Ammonium sulfate 21 0 0
- Complete 14 14 14
Sold here with nitrogen: Atlas Granular Urea (46 0 0) by Atlas Fertilizer, Amigo Planters Ammonium Chloride by La Filipina (25 0 0), Agripower 46 0 0 (Locally Blended) Coated by Green Acres Agri Tech and Calcipro by Ramgo (15.5 0 0 with 18.8 percent calcium). Check the FPA registration on the bag and follow the label rate. For the how and when, see our guide to urea fertilizer, and the page on nitrogen deficiency in every crop. In anee.io, Anee, the smart farm technician, reads a photo of the leaf and tells you which nutrient is short.
To keep it away, fertilize every year in splits at the start and middle of the rains, keep a mulch and organic matter on the soil. Keep some shade over the trees.
Phosphorus deficiency in coffee
It develops slowly. Older leaves first show a faint mottled yellowing, then a soft yellow between the veins, and in bad cases dead spots. Old leaves may also take on a pink or purple tint. Roots stay small, the tree grows slowly, and flowering and fruit set come late. You see it most at this stage: nursery and young trees after planting, and before flowering in bearing trees.
Why phosphorus deficiency happens in kape
Acid soils that lock up phosphorus, and soils low in organic matter. On coffee farms, even moderately acid soils at pH 5.6 to 6 are often very low in phosphorus.
How to tell it apart
Nitrogen deficiency makes the whole tree pale, not mottled or purplish. Magnesium deficiency also yellows old leaves between the veins. To be sure, soil test for available phosphorus and pH, plus a leaf test of the third or fourth leaf pair on a fruiting branch. Healthy leaves test 0.14 to 0.18 percent phosphorus. Leaves at 0.05 to 0.08 percent are short.
What to apply for phosphorus deficiency
Apply a phosphorus fertilizer near the roots, following the soil test. Superphosphate 0 20 0 acts fast. Rock phosphate and bone meal work slowly. You can also use 16 20 0 or Ammonium phosphate 18 46 0. Give a foliar spray of DAP (Ammonium phosphate 18 46 0) at 2 percent (20 grams per liter, 320 grams in a 16 liter sprayer) for a quick fix. Lime very acid soils, since phosphorus is most available near pH 6.5. Give 200 to 500 grams of Complete 14 14 14 a young tree, up to 1 to 2 kg a bearing tree, when the rains begin.
- Ammonium phosphate 18 46 0
- 16 20 0
- Superphosphate 0 20 0
- Complete 14 14 14
- Agricultural lime
Sold here with phosphorus: Philphos 18 46 0 (Di Ammonium Phosphate), Atlas Super Gro (16 20 0) by Atlas Fertilizer, Amigo Planters Granular Single Super Phosphate by La Filipina (0 18 0 with 11 percent sulfur) and Triple Super Phosphate by Newman Chemicals (0 46 0). Check the FPA registration on the bag and follow the label rate. For the how and when, see our guide to 16 20 0 fertilizer, and the page on phosphorus deficiency in every crop.
To keep it away, put phosphorus in the planting hole, add compost or manure every year, and lime acid soils based on a soil test.
Potassium deficiency in coffee
Only the older leaves show it. A yellow band forms along the leaf edge, then dark brown dead spots appear on the edge and grow until the whole edge is dark brown while the area along the midrib stays green. Young leaves stay normal. Badly hit leaves fall early and branches can die back. You see it most at this stage: bearing trees, most of all while the berries grow and fill, when potash demand peaks.
Why potassium deficiency happens in kape
Sandy or porous soils and heavy rain that leach potash, heavy crops that carry potash away in the pulp. Heavy liming or magnesium that crowd out potash. Long dry spells also cut uptake.
How to tell it apart
Magnesium deficiency also starts on old leaves. But its spots are sunken and light brown in a wide band, with yellowing between the veins near the midrib. To be sure, leaf test of the third or fourth leaf pair on a fruiting branch, at or before flowering. Healthy leaves test 2.6 to 3.9 percent potassium. Leaves at 0.4 to 1.1 percent are short.
What to apply for potassium deficiency
Apply Muriate of potash 0 0 60 to the soil under the canopy in split doses, following the soil test. For a quick fix spray Sulfate of potash at 10 grams per liter (160 grams in a 16 liter sprayer) with a sticker in the morning. Mature coffee takes up 150 to 250 kg of potash per hectare a year, about as much as nitrogen.
- Muriate of potash 0 0 60
- Sulfate of potash 0 0 50
- Complete 14 14 14
Sold here with potassium: Atlas Muriate of Potash (MOP) by Atlas Fertilizer (0 0 60), Simplot Sulfate 0 0 50 by Nutranta, Potassium Nitrate by Parafield (13 0 46) and Qrop Mix Production 14 0 23 plus 13 Cao by Farmtech Agriland (14 0 23 with 9.3 percent calcium). Check the FPA registration on the bag and follow the label rate. For the how and when, see our guide to potash fertilizer, and the page on potassium deficiency in every crop.
To keep it away, give potash every year together with nitrogen, in splits during the rains, and return pulp and prunings to the field. Keep organic matter up with compost, manure or crop residues.
Boron deficiency in coffee
The youngest leaves come out light green, small, curved and leathery, mottled with small dead spots and with dead tips and uneven edges. The tip bud grows abnormally and can die, and the side branches show the same on their newest leaves. Older leaves stay normal. Flowers drop, fruit set is poor and beans can be hollow. You see it most at this stage: new flushes and flowering, often after a long dry season.
Why boron deficiency happens in kape
Soils low in boron, heavy liming, high rates of muriate of potash, and long droughts or very heavy rain. Boron shortage is common: about 29 percent of coffee leaf samples test below the critical level.
How to tell it apart
Calcium deficiency also damages young leaves and kills the tip bud, but the leaves turn bronze along the edges and cup downward. Zinc deficiency gives narrow, strap like leaves with green veins on a yellow background and short internodes, without dead spots and tips. To be sure, leaf test of the third or fourth leaf pair on a fruiting branch. Healthy leaves test 31 to 52 ppm boron. Leaves near 9 ppm are short.
What to apply for boron deficiency
Give Borax to the soil at 4 grams per tree, or a foliar spray of Borax at 1 gram per liter (16 grams in a 16 liter sprayer). Give a 0.2 percent Borax spray (2 grams per liter, 32 grams in a 16 liter sprayer). Do not mix borax with calcium or ammonium fertilizers in the same tank. Boron is toxic in excess, so do not repeat high doses without a test. Give boron before flowering: flowers and fruit set need it most.
- Borax
- Solubor
Sold here with boron: Etifert 11 (Borax Decahydrate) by Zetryl Chem (11 percent boron), Fertibagra 15G by Unilox Far East Resources (14.6 percent boron), B17 (Boric Acid) by Newman Chemicals (17 percent boron) and Better Yield by Bacphil Planters Fertilizer (0 0 0.9 with 10 percent boron). Check the FPA registration on the bag and follow the label rate. For the how and when, see our guide to foliar fertilizer, and the page on boron deficiency in every crop.
To keep it away, keep organic matter up, do not overlime, and add a small boron dose before flowering on soils that tested low. Test the soil every two or three years.
Zinc deficiency in coffee
The youngest leaves yellow between the veins, at first just like iron deficiency. Later new leaves stay small and narrow, often strap like, with dark green veins, mostly along the midrib, on a yellow green background. Internodes stay short so leaves bunch into a rosette. Older leaves look normal. Berries can be misshapen and fruit develops poorly. You see it most at this stage: new flushes before and around flowering.
Why zinc deficiency happens in kape
High pH or overlimed soils, heavy phosphate fertilizer, and soils low in organic matter. Zinc is most available between pH 5 and 7.5.
How to tell it apart
Iron deficiency also yellows young leaves between green veins, but the leaves grow to normal size and shape and do not bunch. Boron deficiency also deforms new leaves, but with dead spots, dead tips and a dying tip bud. To be sure, leaf test of the third or fourth leaf pair on a fruiting branch. Healthy coffee leaves test 18 to 25 ppm zinc. Below about 10 to 15 ppm is deficient.
What to apply for zinc deficiency
In bad cases give a morning spray of Zinc sulfate at 2 grams per liter (32 grams in a 16 liter sprayer) mixed with 2.5 grams per liter of lime (calcium carbonate). Give Zinc sulfate at 0.5 percent (5 grams per liter, 80 grams in a 16 liter sprayer). Do not apply zinc on the same day as phosphate fertilizer. Give 50 to 100 grams of Zinc sulfate a young tree and 100 to 250 grams a bearing tree a year under the canopy.
- Zinc sulfate
- Agricultural lime
Sold here with zinc: Harvester Zinc Sulphate Heptahydrate by Universal Harvester (22 percent zinc), Tierramino ZN by Unilox Far East Resources (7 0 0 with 10 percent zinc), Liquid Chelate Zinc with Sulfur by Sagrex (10 percent zinc and 5 percent sulfur) and Nemes Foliar by SCL Filipinas (4.8 0 0 with 10 percent zinc, 4.9 percent boron and 4.8 percent magnesium). Check the FPA registration on the bag and follow the label rate. For the how and when, see our guide to fertilizer with zinc, and the page on zinc deficiency in every crop.
To keep it away, avoid overliming and very heavy phosphate, and spray zinc before flowering where leaf tests run low. Test the soil every two or three years.
Magnesium deficiency in coffee
Older leaves first go pale along the edges, then sunken, yellow brown to light brown dead spots form in a wide band along the edge. The leaf also yellows between the veins, most of all near the midrib. Leaves can curl or cup and drop early after a long shortage. Young leaves stay normal. You see it most at this stage: bearing trees, mostly as the berries mature.
Why magnesium deficiency happens in kape
Acid, sandy, leached soils and heavy use of potash or lime, which compete with magnesium.
How to tell it apart
Potassium deficiency also starts at the edge of old leaves. But its spots are dark brown and join into a solid burnt edge, without yellowing between the veins. To be sure, leaf test of the third or fourth leaf pair on a fruiting branch. Healthy leaves test 0.30 to 0.35 percent magnesium. Leaves at 0.04 to 0.11 percent are short.
What to apply for magnesium deficiency
Give Magnesium sulfate at 32 grams per tree, placed in a band near the tree after a soil test. On acid soils Dolomite gives magnesium and lime together and keeps the problem away over time. Do not apply magnesium and potash fertilizer at the same time. Put the soil dose in before planting or when the rains begin. Sprays show results in 10 to 14 days.
- Magnesium sulfate (Epsom salt)
- Kieserite
- Dolomite
Sold here with magnesium: Dolomite by A6 Agrisource (24 percent calcium and 11 percent magnesium), Agsmart Kieserite Granule (20 percent sulfur and 16.3 percent magnesium), DDDD Planter's Choice Magnesium Sulphate Monohydrate by Modern Time (15.1 percent magnesium) and Zetryl MAG 9 by Zetryl Chem (9 percent magnesium). Check the FPA registration on the bag and follow the label rate. For the how and when, see our guide to complete fertilizer, and the page on magnesium deficiency in every crop.
To keep it away, use Dolomite instead of plain lime on acid soils and keep potash and magnesium in balance.
Calcium deficiency in coffee
Young leaves turn bronze, mostly along the edges, while the area along the midrib stays green. They do not open fully and cup downward. Later the newest leaves die and the tip bud dies back. Roots stay short and weak, and berries can be misshapen. You see it most at this stage: new flushes and while berries fill.
Why calcium deficiency happens in kape
Very acid soils, sandy soils that leach, and heavy potash or phosphorus, which push calcium out.
How to tell it apart
Boron deficiency also hits young leaves and the tip. But leaves are small, curved and spotted, with dead tips, not bronzed and cupped. To be sure, soil test for pH and calcium, and a leaf test of the third or fourth leaf pair. Healthy leaves test 0.94 to 1.16 percent calcium. Leaves at 0.36 to 0.55 percent are short.
What to apply for calcium deficiency
On acid soils give 340 grams of lime per tree per year. Use Dolomite if magnesium is also low. On soils that are not acid use Gypsum. Give a calcium chloride spray at 1 to 2 percent for a quick fix on leaves. Lime 2 to 4 weeks before planting. Calcium sprays go on young fruit from fruit set.
- Agricultural lime
- Dolomite
- Gypsum
- Calcium nitrate
Sold here with calcium: Planters Products Lifelime (36.2 percent calcium), Dolomite by A6 Agrisource (24 percent calcium and 11 percent magnesium), Calcipro by Ramgo (15.5 0 0 with 18.8 percent calcium) and Philphos Gypsum (22.2 percent calcium and 17.4 percent sulfur). Check the FPA registration on the bag and follow the label rate. For the how and when, see our guide to fertilizer for tomatoes, and the page on calcium deficiency in every crop.
To keep it away, lime acid soils based on a soil test and keep potash and phosphorus in balance.
Sulfur deficiency in coffee
The youngest leaves turn evenly pale, with a faint yellow between the veins that is strongest along the midrib. Unlike nitrogen shortage, the leaves keep their glossy shine. New leaves stay small, internodes are short and shoots grow slowly. In long cases older leaves pale too. Fruit set drops and ripening is late. You see it most at this stage: new flushes and berry maturing.
Why sulfur deficiency happens in kape
Soils low in organic matter, sandy soils that leach, burning of prunings and weeds. Years of urea and muriate of potash with no sulfur source.
How to tell it apart
Nitrogen deficiency also gives pale leaves, but the tree loses its shine and the old leaves yellow too. Iron deficiency gives a sharp net of green veins on a yellow or cream young leaf. To be sure, leaf test of the third or fourth leaf pair on a fruiting branch. Healthy leaves test 0.12 to 0.17 percent sulfur. Leaves at 0.04 to 0.05 percent are short.
What to apply for sulfur deficiency
Use a sulfur carrying fertilizer such as Ammonium sulfate 21 0 0 or Superphosphate 0 20 0 in place of part of the urea. Give sulfur dust at 10 grams per tree on sulfur deficient soils, and Gypsum on alkaline soils. Give it at planting or with the first side dress.
- Ammonium sulfate 21 0 0
- Gypsum
- Superphosphate 0 20 0
Sold here with sulfur: Atlas Ammosul 21 0 0 by Atlas Fertilizer (21 0 0 with 24 percent sulfur), Philphos Gypsum (22.2 percent calcium and 17.4 percent sulfur), Harvester Sulphate of Potash by Universal Harvester (0 0 50 with 17.5 percent sulfur) and Agsmart Kieserite Granule (20 percent sulfur and 16.3 percent magnesium). Check the FPA registration on the bag and follow the label rate. For the how and when, see our guide to ammonium sulfate fertilizer, and the page on sulfur deficiency in every crop.
To keep it away, keep ammonium sulfate in the yearly program, return prunings as mulch instead of burning them, and build organic matter. Test the soil every two or three years.
Iron deficiency in coffee
The youngest leaves turn light green between the veins, then yellow and finally almost creamy white. But every vein stays green and stands out as a clear net. The leaves grow to near normal shape but can be thin and small. Older leaves stay green. In bad cases leaf tips and edges brown, leaves drop and fruits stay small. You see it most at this stage: new flushes, most often after waterlogging or on limed spots.
Why iron deficiency happens in kape
High pH or overlimed soils and waterlogged soils. Low potash can bring it on. Many tropical soils already hold plenty of iron, so test before you treat.
How to tell it apart
Zinc deficiency starts the same way, but the leaves turn narrow and strap like and bunch into a rosette. Sulfur deficiency gives an even pale leaf without the sharp green vein net. To be sure, soil test for pH and check drainage. Test the third or fourth leaf pair. Healthy leaves hold 43 to 61 ppm iron, and short ones 1 to 25 ppm.
What to apply for iron deficiency
Give a foliar spray of Ferrous sulfate at 0.5 percent (5 grams per liter, 80 grams in a 16 liter sprayer). Give 6 grams of Ferrous sulfate per tree to the soil where a test shows low iron. Fix drainage where water stands. Spray the young leaves in the cool of the day, soon after sunrise or near sunset.
- Ferrous sulfate
Sold here with iron: DDDD Planter's Choice Ferrous Sulphate Heptahydrate by Modern Time (19 percent iron), Ferrous Sulfate Monohydrate by Zetryl Chem (30 percent iron), Ferrous Sulphate Monohydrate by Newman Chemicals (30 percent iron) and Liquid Chelate Iron with Sulfur by Sagrex (5 percent iron and 3 percent sulfur). Check the FPA registration on the bag and follow the label rate. For the how and when, see our guide to foliar fertilizer, and the page on iron deficiency in every crop.
To keep it away, do not overlime, drain wet spots and keep potash in balance. Test the soil every two or three years. Keep organic matter up with compost, manure or crop residues.
A soil test is the surest check for any coffee nutrient deficiency. Before you buy, ask your Municipal Agriculture Office where to send a soil sample. The DA regional soil laboratories test soil, and the result says how much of each fertilizer your kape needs. That saves money, because extra fertilizer is money lost.
Open the Nutrient Deficiency Finder, pick kape, 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
- The cropping calendar dates every fertilizer application of your season
Coffee nutrient deficiency questions
Why are my kape leaves turning yellow?
What fertilizer fixes nitrogen deficiency in coffee?
What fertilizer fixes phosphorus deficiency in coffee?
What fertilizer fixes potassium deficiency in coffee?
How do I know which nutrient my kape lacks?
- Nagao, Kobayashi and Yasuda 1986, Mineral deficiency symptoms of coffee (UH CTAHR RES 073)
- UH CTAHR Hawaii Coffee Ed: How to take coffee leaf and soil samples
- Yara: Nutritional summary, coffee
- Pacific Pests, Pathogens and Weeds fact sheet: Coffee brown eye spot
- Francisco, Labajo and Ebuna 2022, Soil quality assessment on coffee farms in Pigtauranan, Bukidnon, Philippines
- UH CTAHR Hawaii Coffee Ed: Nutritional problems
- Kawabata and Nakamoto, Spraying to suppress coffee leaf rust in Hawaii (UH CTAHR PD 118)
- U.S. Borax: Boron and coffee plant nutrition
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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