This is a great time of year to take your houseplants outside for a bath. Insect and mite populations can sometimes build unnoticed, but not to worry. Take houseplants outside and gently hose them off. This will not only wash away harmful pests, but will remove dust from the leaf surfaces and leave plant pores cleaner and able to breathe easier.
If you don't want to hose them off, put an old cotton sock on each hand, dampen, then slide the leaves
between your palms.
Do not use anything else (mayonnaise, plant shine products, etc). They do more harm than good.
Commented on Jul 14, 2012
Having drought conditions here in Australia any leftover water from the kettle goes on my
indoor plants,as we have water restrictions most of the year. No using hoses to water outdoor gardens nor to wash cars.