Phaseolus lunatus Fine Webbing - Causes & Fixes

Jump to cause: Two-Spotted Spider Mite Infestation Tetranychus urticae (European Red Mite) Outbreak Fall Webworm Infestation

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Two-Spotted Spider Mite Infestation

Spider mites are highly common pests for Phaseolus lunatus, particularly in warm, dry conditions. They feed on the underside of leaves by piercing cell walls, leaving behind fine silk webbing as they move and lay eggs.

Very Common

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How to confirm: Hold a white piece of paper under a leaf and tap the leaf to see if tiny crawling dots fall onto the paper.

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1 Immediately spray the plant, especially the undersides of leaves, with an organic insecticide to kill existing mites and larvae.

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

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2 Increase humidity around the plant and ensure the environment stays moist, as spider mites thrive in hot, dry conditions.

3 Carefully wipe down leaves with a damp cloth to physically remove webbing and any remaining pest populations.

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Tetranychus urticae (European Red Mite) Outbreak

Often closely related to two-spotted mites, these mites thrive in low humidity environments typical of lima bean cultivation. The fine webbing is a protective structure for their colonies, often accompanied by stippling (tiny yellow spots) on the foliage.

Very Common

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How to confirm: Inspect the undersides of the older leaves for clusters of reddish or yellowish microscopic dots.

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1 Apply an organic miticide or insecticide spray to the plant to eliminate the mite population and destroy their webbing.

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

$10

In Stock

2 Increase local humidity around the plant to make the environment less hospitable for the mites.

Flora Premium Plant Mister

Spray Bottles

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3 Gently wipe the leaves with a damp cloth to physically remove webbing and any visible mite colonies.

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Fall Webworm Infestation

While more common in larger silk nests rather than fine individual webbing, certain lepidopteran larvae can create silken structures on bean foliage. These larvae consume the leaf tissue, often leaving behind skeletal remains of the leaves.

Common

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How to confirm: Look for larger, denser clumps of silk that contain visible caterpillars or hollowed-out leaf fragments.

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shopping_cart Recommended Products

1 Inspect the plant for larvae and manually remove any visible caterpillars or silk nests to reduce the immediate population.

2 Apply an organic insecticide spray to eliminate remaining larvae and protect new growth from further feeding.