Is a terrarium an option? A smaller glass container could keep plants in the living room at the desired humidity. I think they look lovely, too.
Blue Onion said:
I have an ultrasonic humidifier for my boys bedroom, as Utah is extremely arid and I read that it will help his asthma. I can adjust how much vapor is coming out.. and when they have colds I ramp it up to max. By morning it's nearly used up an entire gallon of water. I've read they only really increase humidity locally within a room, but that is exactly what you need.. so I suggest you look into a model that has a large reservoir and adjustable output.. then find what level allows it to run all day while you are gone but still increase the localized humidity. (I have seen research that shows pebble trays only increase humidity in the inch of air above the tray.. not up to the level where the plants are.. so I stopped using them personally and have not seen a negative impact).
@Balgay.Hill, having spent 10 years in the tropics as a child where humidity levels averaged over 70%, I'm intrigued to know what you are growing?
I would worry a bit about the front room, the walls and furniture, if you raise the humidity much. Damp rooms aren't terribly healthy in the UK. You don't want to get mould spores started.
I periodically (say, once a week) move my plants that like humidity the most (including calatheas) onto the coffee table, crowd them together and run a diffuser that's filled with distilled water instead of oils. I call it their spa time. Seems to work fine for me - they're all looking very happy.
The two pot method is a discrete way to increase humidity levels for an individual houseplant, without having to compromise the aesthetics or location of your plant.
Put your houseplant pot into a pot that is 1-2 inches in diameter larger than the inner pot. Fill the gap with sphagnum moss and soak this with water. The moss will hold onto the water and dry out slowly over the space of a few days, releasing the water vapour into the air around your plants.
With this method, it is best to make sure the inner and outer pots both have drainage holes, to prevent water building up at the base of the outer pot, which could potentially cause root rot for your plant.
Or, what about an indoor greenhouse! This caught my eye: