Spider mites on houseplants
Indoors the mite can turn up at any time of year. Look for fine pale mottling on the upper leaf and mites, eggs and cast skins beneath; webbing means a heavy population. Separate the plant from the others, and spray or mist the leaf undersides with water daily to knock numbers back — the RHS notes humidity helps but will not control mites on its own. The predator needs humid air to establish.
At a glance
- Damage
- Pale stippling, bronzing, webbing under leaves
- Type
- Sap feeding
- Settings
- Under glass, Field, Garden, Indoors
- Threshold
- Pale mottling on the upper leaf, mites beneath
- Release
- Phytoseiulus persimilis
- Rate
- 2–50 /m² per release (supplier range)
How to confirm it
Confirm with a 10× hand lens on the leaf underside: oval yellowish-green mites with a dark blotch on each side, round translucent eggs, white cast skins and fine webbing. Tap a leaf over white paper and they walk off.
Identification, lifecycle, degree days and every control option are on the full Two-spotted spider mite profile. Not sure it is this pest? Answer four questions about the damage.
Work it out
How many do I need?
Carries Phytoseiulus persimilis and houseplants through so nothing is re-entered. Open the calculator →