When a plant looks unwell, it is natural to suspect a pest or disease. Indoors, though, Clemson University notes that most houseplant problems have environmental or cultural causes: watering, light, temperature or a build-up of fertiliser salts.
Yellowing, wilting, brown leaf tips and leaf drop can all come from care rather than from any organism. Iowa State University suggests checking first whether the plant is getting the light, water, humidity, temperature and feeding its species needs.
So before treating, ask a few questions. Has the plant moved recently? Is the mix staying wet, or drying out completely? Is there a crusty white layer on the mix or pot rim from fertiliser salts? Is it by a cold draught, a heater or an air-conditioning vent?
If you find no pests during your look-over and the answers point to a care issue, fix the care. Sprays will not help a plant that is overwatered or in the wrong light.
Key points
- Most indoor plant problems come from care, not pests.
- Check light, water, temperature and fertiliser first.
- Only treat for pests when you have actually seen them.
Try this
For one plant with a problem, write down its light, when you last watered, and where it sits relative to vents and windows.
Check yourself
Read more in the reference
Sources
Marking a lesson done is kept on this device only.