Hoya spider mites
Spider mites are almost invisible individually, so they are usually found by their damage: a fine pale speckling across a hoya leaf that no watering problem produces. They breed fastest in warm dry air, which is why they arrive in winter.
What is specific to this plant
- Hoyas are epiphytes with thick waxy leaves that store water, so they want to dry out far more than their leafy neighbours do.
- Do not cut off the bare stalk a flower cluster came from. Hoyas rebloom from the same spur for years, and removing it costs you next year's flowers.
- Long bare vine with no leaves is normal growth reaching for support, not a symptom.
What it could be, and how to tell
These look alike in a photograph, so each one below lists what you would ALSO see if that is the cause. Work down the list and stop at the one where the other symptoms match too.
1. Mites on the soft new growth while old leaves look clean
What else you would see
- damage concentrated on the newest leaves and the growing tips
- mature waxy leaves further back showing nothing at all
- new leaves opening distorted or marked rather than smooth
- fine webbing between the tip and the youngest leaf
What to do
- Rinse the growing tips and the youngest leaves thoroughly, undersides included, and repeat every few days.
- Check every tip on the plant, since a vine can have many and they are easy to overlook.
- Raise the humidity around the plant, which slows them down.
- If you choose a treatment product, follow its label exactly. The label is the legal instruction and it overrides anything written here.
2. Spider mites
What else you would see
- fine pale stippling or speckling across the leaf rather than solid patches
- very fine webbing where the leaf meets the stem
- a dusty look to the underside of the leaf, worst in warm dry air
What to do
- Isolate the plant from your others straight away, before anything else.
- Rinse the leaves thoroughly, undersides included, with a strong spray of water, and repeat every few days. Mites breed faster than a single treatment can keep up with.
- Raise the humidity around the plant. Mites thrive in warm dry air and struggle in humid air.
- If you choose to use a treatment product, follow the label on it exactly. The label is the legal instruction and it overrides anything written here.
3. Dry air letting the population explode
What else you would see
- onset in winter, once the heating is on
- the plant sits near a radiator or a vent
- other plants nearby starting to show the same stippling
What to do
- Raise the humidity around the plant and move it away from the heat source.
- Rinse the foliage regularly. Physical removal is what keeps the numbers down between anything else you do.
4. Brought in on a new plant
What else you would see
- a new plant, a cutting or a bunch of flowers arrived in the last few weeks
- the worst affected plant is the newest one
- damage spreading outward from one plant to its neighbours
What to do
- Isolate anything new for a few weeks before it joins your other plants.
- Treat every plant that was standing near the affected one, not only the one showing damage.
Common questions
How do I confirm spider mites rather than dust?
Hold white paper under a leaf and tap it firmly. Dust sits still. Mites walk. That takes ten seconds and settles it.
Do I have to throw the plant away?
Rarely. Mites are beatable with persistence: isolate, rinse thoroughly and repeatedly, and raise the humidity. What fails is treating once and assuming it worked.
Will they spread to my other plants?
Yes, readily, especially where leaves touch. Isolate the affected plant first and check its neighbours before you treat anything.
Before you act on any of this
This is general plant care guidance for a plant, not advice about people or animals. We never tell you whether a plant is safe to eat or touch, and we never tell you a plant is safe for a child or a pet. If a child or animal may have eaten any part of a plant, contact Poison Control (US 1-800-222-1222) or a vet immediately rather than reading further.
Treatment advice here is deliberately category level. We do not give product names, mixing ratios or application intervals. Whatever the label on the product in your hand says is the instruction that counts, and following it is your responsibility.
Where this comes from
The general horticultural facts behind this differential come from published university extension and Royal Horticultural Society guidance. What is specific to this plant, and the order the causes are ranked in, is ours, and the methodology page says where that reasoning stops being reliable.
- Integrated Pest Management (I.P.M.) for Spider MitesClemson Cooperative Extension Home and Garden Information Center
- Spider MitesUC Statewide IPM Program, University of California
- Common Houseplant Insects and Related PestsClemson Cooperative Extension Home and Garden Information Center
- Diagnosing Houseplant Problems from Improper Environmental ConditionsIowa State University Extension and Outreach
- Glasshouse red spider miteRoyal Horticultural Society
Other hoya problems
Not sure which one it is?
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