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Onion Sonic F1 Brown Leaf Tips
eco Brown Leaf Tips

Onion Sonic F1 – Brown Leaf Tips

Why does your Onion Sonic F1 have brown leaf tips? Diagnose the cause and fix it with our step-by-step guide.

yard View full Onion Sonic F1 care guide
Jump to cause: Salt Accumulation (Fertilizer Burn) Water Stress (Drought or Fluctuating Moisture) Anthracnose (Colletotrichum spp.) Nutrient Deficiency (Potassium)

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Salt Accumulation (Fertilizer Burn)

Onions are sensitive to high concentrations of soluble salts in the soil. Excess nitrogen or potassium from over-fertilization draws moisture out of the leaf tips, causing them to desiccate and turn brown.

Very Common
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How to confirm: Check if you have recently applied high-nitrogen fertilizer or if white crusty mineral deposits are visible on the soil surface.
build How to fix it
shopping_cart Recommended Products
1 Flush the soil thoroughly with plenty of fresh, distilled, or rainwater to leach out the accumulated mineral salts from the root zone.
2 Check the current soil moisture levels to ensure the flushing process hasn't left the medium waterlogged, using a moisture meter.
GROWIT Soil Moisture Meter - Blue
GROWIT Soil Moisture Meter - Blue
Water Meters
$12
In Stock
3 Avoid applying any further nitrogen or potassium-rich fertilizers until the plant shows signs of recovery and the soil salinity has decreased.
FoxFarm Grow Big Liquid Plant Food 1 Quart
FoxFarm Grow Big Liquid Plant Food 1 Quart
0.9 L • 1 pcs
$30
In Stock
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Water Stress (Drought or Fluctuating Moisture)

Onion bulbs require consistent moisture to develop properly. Rapid drying of the soil or periods of drought cause the extremities of the foliage to die back first.

Very Common
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How to confirm: Feel the soil several inches below the surface to see if it has become bone-dry and hard.
build How to fix it
shopping_cart Recommended Products
1 Check the soil moisture level immediately using a moisture meter to determine if the soil has reached a drought state.
GROWIT Soil Moisture Meter - Blue
GROWIT Soil Moisture Meter - Blue
Water Meters
$12
In Stock
2 Establish a consistent watering schedule to prevent the soil from drying out completely between waterings, ensuring the bulb remains hydrated.
Chapin 48000 0.5G Watering Can
Chapin 48000 0.5G Watering Can
2.3 L • Recycled Plastic
$12
In Stock
3 Apply a layer of organic mulch or vermiculite to the soil surface to help retain moisture and reduce evaporation.
Back to the Roots Organic Vermiculite 24qt
Back to the Roots Organic Vermiculite 24qt
22.7 L • Vermiculite
$42
In Stock
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Anthracnose (Colletotrichum spp.)

This fungal pathogen can cause necrotic lesions that appear as brown, sunken spots or tip dieback on onion leaves, especially in humid conditions.

Common
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How to confirm: Inspect the base of the leaves for dark, water-soaked lesions or small, fuzzy fungal growth.
build How to fix it
shopping_cart Recommended Products
1 Apply a fungicide to control the spread of the Colletotrichum fungus and prevent further lesions on the leaves.
Bonide Captain Jack's Copper Fungicide 32 oz
Bonide Captain Jack's Copper Fungicide 32 oz
0.9 L • 1 pcs • Organic
$12
In Stock
2 Remove and destroy all infected plant debris to prevent the pathogen from overwintering in the soil.
3 Improve air circulation around the plants and avoid overhead watering to reduce the humidity that promotes fungal growth.
warning

Nutrient Deficiency (Potassium)

A lack of potassium can lead to marginal chlorosis and subsequent browning of the leaf edges in Allium species.

Common
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How to confirm: Observe if the browning follows the outer margins of the leaves rather than appearing as random spots.
build How to fix it
shopping_cart Recommended Products
1 Apply a potassium-rich organic fertilizer to the soil to address the deficiency and prevent further marginal browning.
FoxFarm Bush Doctor Kelp Me Kelp You Liquid Seaweed Fertilizer 1 Quart
FoxFarm Bush Doctor Kelp Me Kelp You Liquid Seaweed Fertilizer 1 Quart
0.9 L • 1 pcs
$32
In Stock
2 Monitor soil moisture levels using a moisture meter to ensure consistent hydration, as water stress can exacerbate tip burn.
GROWIT Soil Moisture Meter - Blue
GROWIT Soil Moisture Meter - Blue
Water Meters
$12
In Stock
3 Ensure the plant is receiving adequate sunlight and nutrients by supplementing with a balanced liquid fertilizer during the growing stage.
FoxFarm Grow Big Liquid Plant Food 1 Quart
FoxFarm Grow Big Liquid Plant Food 1 Quart
0.9 L • 1 pcs
$30
In Stock

Other Onion Sonic F1 problems

Your plant might also be experiencing one of these issues:

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