Chayote Nutrient Deficiency: Signs, Causes and the Fertilizer That Fixes It
Chayote nutrient deficiency is one of the first things to check when the leaves of your sayote (chayote) turn yellow, purple or burnt at the edges. On Philippine farms the usual ones are nitrogen, potassium, phosphorus, boron, magnesium and zinc. 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, potassium, phosphorus and magnesium move inside the plant, so a shortage shows on the old, lower leaves first. But boron and zinc 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 chayote nutrient deficiency you have, and a soil test confirms it. Each one below has its signs, its causes and its fix.
Chayote nutrient deficiency signs, old leaves and young leaves
Shows first on the old leaves
| Nutrient | Where it starts | What you see | Fix with |
|---|---|---|---|
| Nitrogen | old, lower leaves, the whole plant | Older leaves on the vine turn pale yellow and tops for harvest grow slowly. | Urea 46 0 0, Ammonium sulfate 21 0 0 |
| Potassium | old, lower leaves, leaf edges and tips | Older leaves look grey green, then bronze with brown, downturned edges. | Muriate of potash 0 0 60, Complete 14 14 14 |
| Phosphorus | the whole plant, old, lower leaves | Slow vines with small, dark green leaves and late flowering. | Complete 14 14 14, Ammonium phosphate 16 20 0 |
| Magnesium | old, lower leaves, between the veins | Oldest leaves yellow between the veins while the veins stay green. | Dolomite, Magnesium sulfate (Epsom salt) |
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 and tips come out brittle and deformed, with few female flowers and fruits. | Boric acid, Borax |
| Zinc | young leaves and the tip, between the veins | New leaves are small and mottled yellow, with many dead spots. | Zinc sulfate |
Before you buy fertilizer for a chayote nutrient deficiency
So use the table to pick the likeliest chayote 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 chayote
Older leaves fade to yellowish green and the yellowing climbs the vine. Stems are slender and growth slows, so fewer tops and fruits are produced. You see it most at this stage: vine growth and fruiting.
Why nitrogen deficiency happens in sayote
Heavy rain on sloping highland farms that washes nitrogen away, low organic matter, and no side dressing.
How to tell it apart
Magnesium shortage leaves the veins green on old leaves. Shade under a dense trellis also makes inner leaves pale and drop. To be sure, soil test and leaf tissue test.
What to apply for nitrogen deficiency
Side dress urea or ammonium sulfate around the hills based on the soil test. Follow the soil test for the rate. Side dress 5 to 10 grams of Urea 46 0 0 a plant, about 1 to 2 bags per hectare, every two to three weeks from flowering, and water it in.
- Urea 46 0 0
- Ammonium sulfate 21 0 0
- Complete 14 14 14
- Chicken manure
Sold here with nitrogen: Atlas Granular Urea (46 0 0) by Atlas Fertilizer, Crown Champion Ammonium Sulfate by Aqua Hydroponic Prime Ventures (21 0 0 with 24 percent sulfur), 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, add manure or compost to the hills and side dress regularly through the long harvest. Split the nitrogen into two or three doses.
Potassium deficiency in chayote
Older leaves look ashy grey green, then bronze or yellowish brown, with brown edges that cup down and specks along the veins. Stems are slender and roots poor, and fruits fill poorly. You see it most at this stage: fruiting.
Why potassium deficiency happens in sayote
Acid, leached highland soils and heavy rain, and feeding with urea only.
How to tell it apart
Magnesium shortage yellows between the veins first. To be sure, soil test for potassium and a leaf tissue test.
What to apply for potassium deficiency
Apply muriate of potash or complete fertilizer based on the soil test. Follow the soil test for the rate. A usual dose is 1 to 2 bags of Muriate of potash 0 0 60 or Sulfate of potash 0 0 50 per hectare, split from flowering to fruit fill.
- Muriate of potash 0 0 60
- Complete 14 14 14
- Sulfate of potash 0 0 50
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, include potash in the side dressings during fruiting. Keep organic matter up with compost, manure or crop residues.
Phosphorus deficiency in chayote
Growth is held back without yellowing. Stems are slender, leaves are small and darker green, undersides may turn reddish purple, and fruit set comes late. You see it most at this stage: early vine growth.
Why phosphorus deficiency happens in sayote
Acid soils that lock up phosphorus, which are common where sayote is grown in the highlands, and low organic matter.
How to tell it apart
Cold nights in the highlands can also slow growth for a while. To be sure, soil test for available phosphorus and pH.
What to apply for phosphorus deficiency
Apply phosphorus in the hill based on the soil test and lime very acid soil. Follow the soil test for the rate. A usual basal dose is 4 to 6 bags of Complete 14 14 14 per hectare, 10 to 20 grams a hill, mixed into the soil at transplanting.
- Complete 14 14 14
- Ammonium phosphate 16 20 0
- 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, use complete fertilizer or 16 20 0 with manure in the hill at planting.
Boron deficiency in chayote
New leaves and leaf stalks are light, brittle and deformed, internodes are short and tips rosette. Fruit set is poor. You see it most at this stage: flowering and fruit set.
Why boron deficiency happens in sayote
Slightly acid, leached soils that lock up nutrients, plus low organic matter and dry spells.
How to tell it apart
Mite or thrips damage also distorts tips. Look for the pests under the leaves. To be sure, soil test for boron and a leaf tissue test. In a soil test, less than 0.5 ppm of boron is low.
What to apply for boron deficiency
Spray boric acid at 5 grams per liter of water (80 grams in a 16 liter sprayer), alone or mixed with zinc, ferrous and manganese sulfate at the same rate. Spray three times, 15 days apart, starting 60 days after planting. The best mix gave longer vines, earlier flowers and the highest yield. Boron turns harmful just past the right amount, so test the soil first and never spray stronger than this. A usual soil dose is 5 to 10 kg of Borax per hectare (0.5 to 1 kg of boron), mixed evenly with the basal fertilizer.
- Boric acid
- Borax
- Solubor (sodium borate)
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 and use micronutrient sprays only where tests or symptoms show a need.
Magnesium deficiency in chayote
Yellowing between the veins starts on the oldest leaves and moves up the vine. The yellow tissue can brown, die and drop out. You see it most at this stage: fruiting, during fast growth.
Why magnesium deficiency happens in sayote
Low pH, sandy or leached soils, dry spells, and heavy potash or ammonium fertilizer.
How to tell it apart
Nitrogen shortage yellows the whole leaf. Manganese toxicity on very acid soil gives bronze spots. To be sure, soil test for magnesium, potassium and pH.
What to apply for magnesium deficiency
Keep soil pH near 6.5. Before planting use dolomitic lime or magnesium oxide, and feed Epsom salt through drip lines when needed. Leaf sprays rarely fix a serious shortage. A usual dose is 100 to 150 kg of Kieserite or 150 to 200 kg of Magnesium sulfate per hectare at planting. On acid soil, 1 to 2 tons of Dolomite mixed in before planting both limes and feeds. For quick help, spray Magnesium sulfate at 1 to 2 percent (160 to 320 grams in a 16 liter sprayer) two or three times, 10 to 14 days apart.
- Dolomite
- Magnesium sulfate (Epsom salt)
- Magnesium oxide
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 on acid soils before planting. Test the soil every two or three years. Keep potash in balance with magnesium and calcium.
Zinc deficiency in chayote
New leaves are abnormally small and mottled yellow, or evenly pale, and dead spots are common. You see it most at this stage: vine growth.
Why zinc deficiency happens in sayote
Soils where micronutrients are fixed, heavy phosphorus fertilizer and overliming.
How to tell it apart
Virus diseases also make small, mottled leaves. Look for aphids or whiteflies. To be sure, soil test for zinc and pH, and a leaf tissue test. In a soil test, less than 0.8 ppm of zinc is low.
What to apply for zinc deficiency
Spray zinc sulfate at 5 grams per liter of water (80 grams in a 16 liter sprayer) three times, 15 days apart, starting 60 days after planting. It can go alone or mixed with other trace nutrients. A usual soil dose is 20 to 25 kg of Zinc sulfate per hectare (about 5 kg of zinc), mixed with the basal fertilizer. It lasts two or three crops.
- Zinc sulfate
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), Semia by SCL Filipinas (20 percent zinc) and Omex Zynergy by Jardine Distribution (3.8 percent zinc and 2.1 percent copper). 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 excess phosphorus and overliming. Test the soil every two or three years.
A soil test is the surest check for any chayote 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 sayote needs. That saves money, because extra fertilizer is money lost.
Open the Nutrient Deficiency Finder, pick sayote, 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
Chayote nutrient deficiency questions
Why are my sayote leaves turning yellow?
What fertilizer fixes nitrogen deficiency in chayote?
What fertilizer fixes potassium deficiency in chayote?
What fertilizer fixes phosphorus deficiency in chayote?
How do I know which nutrient my sayote lacks?
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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