You can spray the leaves and the soil for example with a swill made of plants. For that you place 100g of fresh random herbs in 1 litre of water and leave it for 24 hours. After that, you can boil it up for half an hour, let it cool down and run it through a sieve. The swill can now be diluted with 2 litres of water and filled in a water-sprayer, so you can protect your green and blooming favorite plants quite effectively.
The most pests like the white fly, spider mites, red spider, aphids, scale insects…. occur due to dry air in the room.