I have a question about bottom watering and also using a humidifier. I primarily have peperomia plants and started bottom watering them. I have been filling a dish washing bin with about 2 inches of water and placing them in it. All of the pots have drainage holes. From what I’ve read it was recommended to leave them in the water for about a half hour. When I leave them in for that long the top two inches of soil are still dry. Should I just leave them in longer? Do I wait until the top of the soil feels moist? Am I doing something wrong? Also, are there any indoor plants that shouldn’t be bottom watered? I ordered a humidifier that is supposed to arrive today from Amazon. I was going to put it on one of the shelves of my plant shelving unit. (Pictured). Does it need to be a specific distance from the all my plants? I was concerned if I put it on a shelf it would be too close to the plants. This shelf is near my bed, too, so it would be helpful for me.