Spider mites are common, tiny garden pests, related to spiders and ticks. Usually microscopic, mites can be found in almost any habitat, including the human body. We refer to some mites based on where they are found: cheese mites, dust mites, eyelash mites.
The term “spider mite” is often used to refer to mites that attack plants. For instance in Oregon, spruce mite is a common pest of spruce and a few other trees. The two-spotted spider mite is a spider mite that feeds on many types of plants. The following information pertains specifically to two-spotted spider mite, and may also be true for other plant-feeding mites.
Spider mites thrive in hot, dry weather and cause damage to many types of ornamental and vegetable plants. In this article you will find information about:
Spider mites are tiny pests that can cause significant damage to plants if left unchecked. Detecting an infestation early is crucial to saving your plants. Here are the most common early signs of spider mites and how to identify them.
What are Spider Mites?
Spider mites belong to the Tetranychidae family of mites. They are closely related to spiders, hence the name spider mites. There are over 1200 species of spider mites the most common being the Two-Spotted Spider Mite.
Spider mites are very tiny, about 1/50th of an inch (0.4 mm) in size. This makes them barely visible to the naked eye. They can be red, green, yellow or brown in color. Their oval-shaped bodies have 8 legs and 2 red eyespots.
Spider mites are sap-sucking bugs that feed on the juices from plant leaves. They use their sharp, needle-like mouthparts to pierce the plant tissues and suck out the nutrients.
How Do Spider Mites Damage Plants?
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Spider mites weaken plants by sucking out chlorophyll and nutrients from the leaves. This disrupts photosynthesis.
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The holes and lesions caused by feeding result in stippling, yellowing, bronzing and curling of leaves.
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Heavily infested leaves turn brown, wither and fall off. This defoliation deprives the plant of nutrition.
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Spider mite feeding reduces plant vigor and stunts growth. Seedlings and young plants are especially vulnerable.
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Large populations build up silken webs on plants which interferes with photosynthesis and traps moisture.
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Spider mites excrete honeydew secretions that encourage mold growth.
9 Early Signs of Spider Mites
1. Tiny Moving Specks on Leaves
Look closely at the undersides of leaves with a magnifying glass The earliest signs are tiny dots crawling slowly across the leaves These are the spider mites themselves,
2. Yellowing or Speckled Leaves
Check the undersides of leaves for tiny yellowish or white speckles or dots. This early stippling is caused by spider mites sucking out cell contents. Leaves may also appear yellow or discolored.
3. Leaf Curling or Cupping
Leaves start curling downwards or cupping up because of the irritation from mite feeding on the undersides. Newer leaves at the top are usually affected first.
4. Browning and Shedding of Leaves
When mite damage is more extensive, leaves turn brown and drop off. Plants look sparse as more and more leaves are lost.
5. Fine Webbing on Leaves
Look for the characteristic webs that mites spin on leaves for protection. Webbing starts out sparse but becomes more extensive as populations grow.
6. Clusters of Eggs on Underside of Leaves
Turn leaves over gently to look for bunches of tiny spherical eggs. They are initially transparent but turn cream, yellow or orange when mature.
7. Presence of Other Pests Like Thrips
Spider mites are often found alongside other pests like thrips, aphids and whiteflies. So be on the look out for these as well.
8. Attraction of Ladybugs and Lacewings
Natural predators like ladybugs and lacewings may start frequenting plants as they hunt spider mite colonies.
9. Damaged Plants Nearby
Spider mites can spread rapidly to nearby plants. So if some plants show damage, check others thoroughly for signs of early infestation.
How to Control Spider Mites
Catching an infestation early makes spider mites much easier to get rid of. Here are some effective organic methods:
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Knock mites off with a strong stream of water. Blast plants with water daily, especially the undersides of leaves. Ensure the pressure is high enough to dislodge mites but not damage plants.
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Apply horticultural oil or insecticidal soap. These suffocate mites on contact while being safe for plants. Coat all leaf surfaces for best results.
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Use Neem oil. The azadirachtin in neem oil works as an insect growth regulator. It inhibits mite feeding, mating and egg hatching.
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Release predatory mites or insects. Predatory mites like Phytoseiulus persimilis specifically target spider mites. Ladybugs, lacewings and minute pirate bugs also feed on them.
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Clean plants regularly. Wipe leaves down with a damp cloth to remove dust, debris and webs which encourage mite growth. Remove badly damaged leaves.
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Provide good culture. Healthy, thriving plants better withstand pest attacks. Ensure proper light, water, humidity, airflow and nutrition.
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Isolate and discard severely infested plants. This prevents mites from migrating further. Remove and destroy fallen leaves and debris.
How to Prevent Spider Mite Infestations
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Check new plants thoroughly before bringing indoors. Quarantine and treat any infested plants.
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Prune plants to improve air circulation and light penetration. This makes for fewer hiding places.
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Hose plants down periodically to keep mite populations in check.
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Avoid high-nitrogen fertilizers that result in soft, succulent growth that attracts mites.
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Release predatory mites or insects like ladybugs as a preventive biocontrol measure.
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Apply horticultural oils and neem oil during early spring and summer as dormant sprays. This kills overwintering mites.
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Control weeds around gardens. Many weeds host spider mites.
Catching an infestation in the early stages is key to effective spider mite management. Keep a close eye on plants and take prompt action at the first signs. Consistent monitoring and prevention will help avoid major crop losses due to these tiny sap-sucking pests.
Types of spider mite damage
Two-spotted spider mite feeds on a wide range of plants. Not all plants respond in the same way: Damage can look a different depending on the plant and leaf type.
Spider mite damage often starts in lower plant growth, expanding into other parts as the mite population increases.
Spider mite damage often starts in lower plant growth, expanding into other parts as the mite population increases. Below are the most common signs that spider mites are present in damaging numbers:
Leaves look pale or unusually yellow, as if they need fertilizer. This initial symptom is not very helpful, as pale, yellow leaves can be caused by a variety of problems.
Leaves have tiny white or yellow spots where mites have been feeding. This feeding removes chlorophyll, the substance that gives leaves their green pigment. Heavy spider mite feeding can result in leaves that lose almost all of the green pigment, but most commonly the pigment is removed in little dots at the feeding area (called stippling).
Some leaf types develop a bronze or brownish cast to them in response to spider mite feeding. Depending on the plant type, bronzing may come after, or instead of, stippling.
Stippling on Leaves
Feeding takes place mainly on the undersides of leaves. Mites use mouth parts to puncture and suck juices from foliage. This sucking action leaves behind a stippled look of tiny white or yellow spots, often requiring a magnifying glass to see. Extensive damage causes holes in the foliage and is a sign of a more severe infestation.
How do you Know if you Have Spider Mites? | Pest Support
FAQ
What does the start of spider mites look like?
The first thing you’re likely to notice is patterns of silvery dots or stippling on the leaves of your plant. Looking closer, you will see small, delicate webs in corners of stems or underneath leaves with what look like tiny white dots scattered throughout. Those are spider mites!
How do you tell if you have spider mites?
- Your plant’s leaves have small brown or yellow spots or look ‘dusty’
- You’ve tried all your usual tricks and your plant still doesn’t look healthy – think yellow, dying leaves or stunted growth.
- There’s ‘webbing’ that kind of looks like a tightly weaved spider web visible on the plant.
Can a plant be saved after spider mites?
probably not. start treating it and the area around it with a miticide. clean any debris off the surface of the soil and off the bases. cut off the worst leaves and burn them with fire! j/k just put them in the trash. leave the smallest leaves and treat that thing every few days.
What can be mistaken for spider mites?
Tenuipalpidae are known as false spider mites because they closely resemble spider mites (family Tetranychidae) or as flat mites because their body is rather flat compared to other mites. Most species that cause damage to cultivated plants belong to the genera Brevipalpus and Tenuipalpus.