Propagation Experimentation

I can't seem to have enough plants these days.  I don't know if this is developing into a mental condition, but I just have this urge to acquire or plant more and more of them!  This can develop into a pretty expensive habit, but luckily I've been curious about and somewhat successful so far with plant propagation.  

One of the aspects of gardening that I never used to like, mostly because I didn't understand it, was plant propagation and care.  I had and still don't really know how to properly prune my plants, nor do I know how to divide my plants without killing them.  Since you can find nearly anything on the Internet these days, I've read up online about propagation techniques but would love to learn how others successfully propagate their plants.

I read up on succulent propagation and tried propagation from leaves, with a pretty low success rate.  I have rooting hormone but have been reluctant to use it before fully understanding the effects of the hormone on the plants and soil.  I didn't realize how long it takes for most succulents to grow, so this has tested my patience the most.  I think I've got "watched pot" syndrome -- I closely observe and tinker with these guys every day expecting to see progress every day, but it's only when I shift my attention to other things that all of a sudden I notice a pup pop up out of nowhere.  Anyway, succulent propagation is the subject of my next entry and, as you'll see, something I haven't quite figured out yet.

I've also experimented with cuttings.  I haven't learned enough yet about botany and plant anatomy to figure out the best places to take cuttings from.  I've successfully taken cuttings from Monstera deliciosa and peace lilies, but everything else has been a stab in the dark, like this guy, a cutting of a philodendron that never rooted :(

If you watch The Big Bang Theory, you'll notice Sheldon and Leonard have an avocado seed rooting in water.  I have nowhere to plant an avocado tree but thought it'd be kinda fun just to see how this turns out.  

This is an elephant ear piece I dug up from the side of the road.  It has since grown into this:

That pretty leaf unfolded and looked healthy for a while, but now it's turning a little yellow and limp, so I think I have some soil and other issues to work on now.  Hopefully I can still save him.

I'm interested in growing house plants that will help clean the air of toxins and other substances.  I read online that this snake plant, or mother-in-law's tongue, though toxic to some pets, removes formaldehyde, xylene, toluene, trichloroethyline from the air, according to a NASA Clean Air Study.  In the same study, the spider plant, which I'm hanging from the ceiling in the bedroom, was shown to remove formaldehyde, xylene, and toluene from the air, and peace lily was shown to remove all of those substances plus benzene, trichloroethylene, and ammonia.  I haven't noticed that the air in our apartment is any fresher, but the mere sight of plants in the house makes me feel more comfortable.  I imagine it'll take a while to propagate these plants, but I'd rather try than buy.