Plant care guide
Peace Lily Spider Mites: Confirm Them, Then Treat
Updated
Why does my Peace lily have spider mites?
Spider mites on a peace lily show as fine pale speckling on the leaves, with tiny moving dots and sometimes silk webbing underneath. Dry indoor air in winter and a plant short of water make outbreaks worse.
What to do first
Confirm mites on the leaf undersides with a hand lens, isolate the plant, and wash the foliage with a forceful water spray. If mites persist, use insecticidal soap or oil with full underside coverage and repeat.
Fine pale speckles across a peace lily’s dark leaves can be spider mites. It is worth checking properly, because brown tips, yellowing and other pests can look similar at a glance. Clemson Extension’s peace lily factsheet lists spider mites among the few insect-type pests of this plant. It advises examining the leaves often.
The good news: a light infestation caught early can usually be washed off.
Check 1: Is it really mites?
Turn several leaves over and look with a hand lens. UC IPM’s spider mite Pest Note describes them as tiny moving dots. Adults are less than 1.3 mm (1/20 in) long, with eight legs and an oval body. They live in colonies, mostly on leaf undersides.
Signs that support mites:
- Stippling. UC IPM says damage first appears as light dots on the leaves. Iowa State Extension’s houseplant spider mite article describes tiny yellowish-green speckles.
- Fine webbing. UC IPM notes that silk webbing separates spider mites from aphids, thrips and other small leaf-underside pests.
- Moving specks on paper. Tap a leaf over white paper. UC IPM says disturbed mites move around rapidly.
The RHS glasshouse red spider mite page adds that the mites are usually yellowish-green with two dark patches, despite the name.
Rule out the look-alikes
| What you see | More likely | Where to read more |
|---|---|---|
| Brown, dry tips with no speckling | Sun, dry mix or low humidity (NC State) | Peace lily brown tips |
| Yellow between green veins | Magnesium deficiency (Clemson) | Peace lily yellow leaves |
| White cottony tufts in leaf joints | Mealybugs | Check stems and leaf bases |
| Small flies around the mix | Fungus gnats | Fungus gnats on peace lily |
If you see no mites, eggs or webbing, do not spray. UC IPM notes that mites are sometimes gone by the time damage is noticed.
Why mites build up indoors
Iowa State says winter is when many people first notice spider mites on houseplants. Dry indoor air and reduced plant vigour seem to favour them. The RHS says this mite thrives in warm, dry conditions.
UC IPM adds that water-stressed plants are damaged most. A peace lily that is often allowed to wilt is more at risk.
What to do
- Isolate the plant. The RHS notes that mites can damage a very wide range of houseplants. Move it away from others.
- Prune the worst leaves. Iowa State suggests cutting off heavily infested portions before treating.
- Wash the leaves. Iowa State recommends a forceful spray of water in the shower or bathtub. UC IPM stresses coverage of the undersides. Let water drain from the pot afterwards.
- Wipe the foliage. NC State’s Spathiphyllum profile notes that wiping the wide leaves with a damp cloth removes some pests that gather underneath.
- Use soap or oil if mites persist. UC IPM prefers insecticidal soap or insecticidal oil, including neem. Both must contact the mites, so wet every underside. Repeat applications may be needed.
- Test first. UC IPM advises trying a product on part of the foliage several days before a full treatment. Do not spray a water-stressed plant or above 32 °C (90 °F).
Do not substitute dishwashing liquid. Iowa State no longer advises it, because modern detergents can harm plants.
When to escalate or discard
Iowa State notes that a small, heavily infested plant is often easier to discard than to restore. A large peace lily can be divided; keep only clean, healthy crowns.
For a severe or recurring problem, the RHS and UC IPM describe predatory mites such as Phytoseiulus persimilis. Avoid broad-spectrum insecticides. UC IPM warns they often kill mite predators and trigger outbreaks.
Prevent the next outbreak
- Check leaf undersides whenever you water, especially in winter.
- Water thoroughly when the mix is dry so the plant is not stressed.
- Wipe dust off the leaves regularly.
- Inspect new plants before they join your collection.
Our spider mites on houseplants guide covers mites across species. The peace lily care guide and peace lily hub cover watering, light and other problems.
References
How this guide was put together: UC IPM, Iowa State University Extension, Clemson Cooperative Extension, NC State Extension and RHS guidance.