Hi Tiff..I guess either,or work, but I prefer tinier pebbles/pea gravel for small plants, and large stones for plants in containers 10" plus.

Most house plants aren't terribly picky about this kind of thing, another reason why they're so prolifically grown inside.

This is not what you asked, but here I go, off on a tangent, possibly out to left field...

Try to group plants together, which is usually a requirement when we start getting quite a few plants. Who has 30 windows?! LOL!

Cooking something that puts a lot of moisture in the air also helps, or boil some water just for the moisture if it gets really dry. (Just don't forget it!) If using the oven for something savory that won't mind the steam, I like to put a pan of water in with whatever I'm cooking. If you have an old-school stove with electric burners where one of the back burners is also a vent for the oven, keeping a pan of water there while using the oven can also increase humidity if it makes the water warmer than the room air.

The dryer vent can be a great source for increasing humidity. They make kits for discharging into the house instead of outside while it's cold outside, keeping all of that lovely heat you've paid for and the humidity that comes with it. The one I really liked had a water reservoir to catch the lint. The only drawback is that you do need to clean this and keep it filled with water, and it's a little project switching over when the seasons change. I also put old pantyhose around the whole thing because it didn't seem like it was totally effective for trapping the lint.

Open the bathroom door after a long steamy shower instead of letting a ceiling fan suck that moist air out of the house.

The coolest setting where everyone is still comfortable is best, the more the central heat runs, the more moisture it takes from the air.

Purple...you're right..grouping plants together is a good idea..Right, who has 1000 windows..lol

I boil water when dh is at work, he'd be a little irked about a gas bill increase..

I don't understand about the dryer vent. What??? :)

Our shower is upstairs. I normally close the door after a shower since Hoyas, Philos and Alocasia are placed in the bathroom. But for those who's bathroom is on the main floor, opening the door allows steam to permeate the air.

Tiff, amongs all the tips, invest in a humidifer. Healthy for people, pets and plants.

You can vent the dryer inside instead of outside, saving/re-using a huge amount of heat and moisture that you pay for instead of having it leave the house. Forgot to say it works best if W/D aren't in the basement. You just have to do something to catch the lint that gets past the filter and into the vent hose.

Haven't done it here because the dryer vents through the floor in the middle of the house, so most of that heat/moisture comes right back up through the floor, we can feel it.

Our bathroom is on the north side with a tiny window that has a porch roof outside of it. So glad it's there though, it's the only bathroom and with 2 guys in here, it's really good to be able to open that window sometimes!

Toni, put some spices in that water and call it potpourri! Which reminds me of those tiny crock pots they make for simmering potpourri. You could probably run one of those for twice as long with half as much gas/electric. Or even a regular crock pot, much more efficient than stove burner.

I can't stand dry air and wish us all more humidity this winter!

Ok, where do I get pea gravel or pebbles? HD sold a 40 pound bag and that is WAY more than I can even think of using right now.

Boiling hot water is a great idea but the kitchen isnt near the plants. so dont think that will work.

Is humidity a big deal though? Something I need to be concerned about? In my research of the plants I have, some of them said it was a requirement...