Spider Mites on Plants

Spider mites are tiny plant-feeding relatives of spiders that can multiply rapidly during hot, dry conditions. They feed by piercing plant cells, often causing stippling, yellowing, bronzing, leaf drop, and fine webbing when populations become heavy.

Know What Spider Mites Look Like

Individual mites are very small and may appear as moving dots rather than obvious insects.

Look for Stippling

Fine pale specks across leaves are a common early sign of feeding.

Watch for Bronzing

Heavy feeding can turn foliage yellow, gray-green, or bronze.

Look for Fine Webbing

Dense populations may produce delicate webbing around leaves, stems, and growing tips.

Check Leaf Undersides

Mites commonly feed and reproduce on the lower leaf surface.

Use a Magnifying Lens

Magnification makes mites, eggs, and shed skins easier to see.

Use the White Paper Test

Tap a suspicious leaf over white paper and watch for tiny moving specks.

Do Not Confuse Webbing With Spider Webs

Ordinary spiders produce larger webs and usually help by feeding on insects.

Inspect Nearby Plants

Mites can spread through a group of plants before severe symptoms are obvious.

Watch Hot Dry Areas Closely

Spider mite populations often increase rapidly during warm, dry weather.

Water-Stressed Plants May Suffer More

Plants already struggling with drought can show severe damage more quickly.

Maintain Appropriate Irrigation

Keep plants adequately watered for the species without creating waterlogged soil.

Reduce Dust Around Plants

Dry dusty conditions can favor mite outbreaks and interfere with some natural enemies.

Wash Foliage When Appropriate

A firm stream of water can physically remove mites from sturdy plants.

Focus on Leaf Undersides

Direct water where mite colonies are most concentrated.

Repeat Physical Removal

One washing may reduce numbers but rarely eliminates every mite or egg.

Avoid Damaging Delicate Plants

Use gentler water pressure on seedlings and fragile foliage.

Remove Heavily Infested Leaves

Pruning a few badly affected leaves can reduce the population when damage is localized.

Do Not Remove Too Much Foliage

Severely defoliating an already stressed plant can make recovery harder.

Dispose of Infested Material Carefully

Do not shake mite-covered leaves across healthy plants.

Isolate Container Plants When Practical

Moving infested pots away from healthy plants may slow spread.

Inspect New Plants Before Introduction

Spider mites can enter a garden, greenhouse, or indoor collection on infested plants.

Watch Greenhouses Closely

Warm protected environments can support rapid mite reproduction.

Understand Natural Enemies

Predatory mites and several beneficial insects feed on spider mites.

Avoid Unnecessary Broad-Spectrum Insecticides

Some insecticides kill mite predators and can allow spider mite populations to rebound.

Know That Mites Are Not Insects

Products labeled for insects do not automatically control spider mites effectively.

Read Product Labels Carefully

Use only products labeled for the crop, pest, and application site.

Cover Leaf Undersides When Required

Many contact treatments work only where spray reaches the mites.

Follow Repeat-Application Directions

Eggs may survive an initial treatment, so label timing matters.

Avoid Spraying During Excessive Heat

Some soaps, oils, and other products can injure foliage under stressful conditions.

Test Sensitive Plants When Appropriate

Plant tolerance differs by species, cultivar, and environmental conditions.

Do Not Mix Products Without Label Approval

Improvised combinations can damage plants or create unsafe applications.

Check Edible-Crop Restrictions

Observe all harvest intervals and crop-specific label requirements.

Monitor After Treatment

Look for living mites and fresh stippling rather than assuming control was complete.

Look for New Healthy Growth

Old damaged leaves may not recover, so improvement is often easiest to judge on new foliage.

Remove Severely Declining Plants if Necessary

A plant overwhelmed by mites can act as a continuing source for nearby plants.

Keep Records of Outbreaks

Note weather, host plants, severity, and management methods that worked.

Inspect Susceptible Plants Earlier Next Season

Early detection usually makes mite populations easier to manage.

Practical Takeaway

Control spider mites by confirming the pest, checking leaf undersides, reducing plant stress, washing or pruning when practical, protecting natural enemies, and using only properly labeled products when additional control is needed.