OOOOOOPS! That's pebble TRAY! You're probably thinking...what the heck is a pebble TREE?! Ha, pretty funny visual. Sorry for the typo!

I can't say as I have no means of testing, but I can't imagine they are effective just as misting isn't effective beyond the time it takes for the water to evaporate.

Too little water in too much air to raise humidity.

The whole house humidifier is a good idea. I had one professionally installed for under $400 I believe. Aprilaire brand. I believe the installation added around $100 to the price of the unit itself so if you and/or hubby are do it yourselfers it would be less than $300.

Still, in the winter you really can't get the indoor humidity up much beyond 50-60% if it's below freezing outside or you will get condensation on your windows no matter how well insulated they are.

If you have a plant area where all the plants requiring the higher humidity are you can run a portable humidifier and point the discharge right at the area for a localized effect.

I think they're effective *IF* and only if you have good air circulation.

The article you posted was very interesting---I too have found the trays completely useless, but many GardenWebers swear by them. In a MN winter my household humidity gets below 12%, and both the plants and myself are miserable. They get dry leaves, and I get nosebleeds, irritable lungs, and eyes that feel like sandpaper. One year I put out about 50 pebble trays and it didn't make one darn bit of difference (as measured by a hydrometer and my nosebleeds!). What *does* help is a humidifier, but even then the humidity won't get over 40%. For those who insist their pebble trays make all the difference---to each their own. :)

Hi Tmac..People are entitled to their opinions, of course, as is the author of the Pebble tray Myth article. LOL

One thing, I agree with Nan about air circulation, which is why running a fan on low during winter months help..You don't have to keep on 24/7, a few hours a day is better than nothing..
In areas where the temps don't freeze, opening a window is best, but places like here in IL, and OH, is just not possible..especially when it's -5..lol..

I believe pebble trays, grouping plants, misting, and of course humidifers will definatly increase humidity..55-60%, which is what the humidity is in my house once heat is turned on, is better than 5%..I have 3 hygrometers, all accurate..Every so often I rotate around the house, even set in the fridge a few times to make sure they were working.

The furnace type is nice, but if you can't afford it, go with a standard humidifer..They work fantastic..
I don't agree w/aiming the mist on plants..I once experimented w/an Iron Cross Begonia and leaves mushed up..
The type I have contains 2, 5 gallon containers you fill up w/water. When filters are working properly, you'll need to refil one to two times a day, but that means it's doing its job. (if you have pets, dogs/cats/birds) the bad thing about humidifers is they tend to attract fur and feathers..we go through 3-4 filters in winter.
BTW, I also have 2 indoor fountains, (small) that I run in winter..You can purchase at Home Depot or Collections Inc. Neither are overly loud, and the streaming waterfall has a soothing sound.
Back to your original question, lol, I think pebble trays work okay, moreso w/smaller plants..I don't think they'd do much w/say a 10" or higher pot.
The object is to make sure there's water in the tray..Depending on tray size, and considering how arid our homes get, it's best to check every 3rd or 4th day.
So, if you use a small fan, tray, mist, and any type of humidifer, the air in your house should be fine..Toni
PS, I really wanted a Pebble Tree..lol

I tried pebble trays last winter for the first time, and they seemed to help, although not enough to keep one of my moth orchids from dropping all its buds. :(

Just a suggestion - I kept my plants in their drip saucers so that they wouldn't sink into the wet pebbles and get waterlogged.

They are much more effective than misting - which may not be a saying a lot, as misting has been shown to be literally useless unless done all day long (and that's no good unless you like rotting plants and mildew). Mist evaporates within a few minutes (which is why the grocery machine-sprays lettuce every few mins) and just doesn't cut it, but trays are great as they work all day, even if less dramatically. They're not perfect and can't substitute for a room machine, but if you keep the pot above the water (on stones or something) and the tray is wide enough to span foliage width, it can make 'the' difference, especially in winter with central htg. all over.

Pebble trees, that really IS a funny visual! I wanted one too!

Well, I am a die-hard believer in pebble trays (tho' not of misting) & of grouping plants together. I will say that I tend to grow smaller things (3-4" pots, going to largest say 6-8"). Especially lots of Hoyas. But in total, maybe 160+ pots so I find keeping them grouped together does help.

My apartment faces due west, on top floor, I get LOTS of HEAT & bright light; I have humidity trays under EVERYTHING except the succulents (moistly Aloes & varied Crassulaceae).

I don't think keeping the drip saucer btwn the plant & the pebbles is a good idea (if I understood that correctly). Otherwise, it interferes w/ the potted plants ability to use some of that moisture by direct evaporation which is what I assume happens (& would negate the whole point of doing this).

The trick is to keep the pot ON TOP OF, NOT IN the pebbles in the water, that way there is no danger of waterlogging.