I really love my having plants in my house. They make my small space brighter and freshen the air I breathe. Though I have several plants that are a few years old, I sometimes get new ones that only live for a month or two. I never understood what might be causing this problem until I found out that certain vegetation tolerates dry air better than others, but all can benefit from being placed near a humidifier.
The air in my bedroom, where I keep my plants, is very dry, and it has been even worse this summer since I'm usually running my air conditioner or a fan to cool the room down. My indoor garden is near the window, so that the sunlight can keep everything green, but the light and heat coming in from the window dry the air out even more. It turns out that lack of moisture in the air wasn't just making me thirstier, it was also damaging the delicate leaves of some of my plants, which eventually killed them.
However, most of the greenery that I have had for a while is thick-leaved and robust, including a cactus. Recently I found out that plants with thicker leaves require less humidity than those with thinner leaves and flowers. This explains why I can't seem to hold on to a delicate orchid for more than a few weeks, while my spider plant has been around for many years. My thin-leaved violet wilts after just a couple of days, even though I water it weekly.
When I found out about the importance of moisture in the air for plants, I got a humidifier for my room right away. I have already noticed that the leaves of all of my plants don't have brown tips the way that they used to, and they stay perky and green between regular waterings.