I am gonna tell you kids a story, with pictures and all, so scoot on over closer to the fire. Hope you enjoy it.

So, once upon a time (July 1st, 2013) grandpa brought home two happy-looking Caladiums in 6 inch pots, 11' and 15' tall.
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Look at these leaves!
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I replanted both into 8' pots with drainage holes (of course!) One plant even had a flower bud in the works, so naturally I was all giddy with anticipation.
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The soil I repotted into was my own artistic interpretation of Al's world-famous 5-1-1 mix (5 parts pine bark, in my case equally split between larger uncomposted particles and very fine composted ones, plus one part each of peat and perlite, with 1 tbsp/gallon garden lime but no controlled release fertilizer added). Perhaps a bit more moisture-retentive than your usual garden variety (haha!) 5-1-1 mix.
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12 days after repotting, I put one of the plants into a windowless bathroom.
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Petrushka told me it was not a good idea (http://forums2.gardenweb.com/forums/load/houseplt/msg0619343722933.html), and she was right! (Thank you! I am learning as I go along!) That Caladium promptly (3-4 days) developed tan/brownish leaf spots where the leaf became very thin, flacid, see-through'ish and felt wilted just in those spots:
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After some googling around, I cut off the three affected leaves, which were the oldest and biggest (and the most beautiful) ones. And of course I had taken the plant out into the light by then. The spots have not appeared on other leaves since then, so I guess grandpa dodged THAT bullet, kids.

Next... The plants were all crowded at the nursery with no space between the pots on the tray at all, and all the leaves were pointing pretty much straight up. Soon (days) after I repotted and gave them more horizontal space, the leaves were kind of bendy. I did not read much into it because the stems (petioles) were firm. I checked the soil and watered the one where the soil felt slightly drier than the other - although none of them were REALLY dry.

What do you know! The one I watered has perked up a little tiny bit (even though its soil was not dry - I swear!), and the one I did not water now has petioles softened to the touch, and the leaves are now drooping even more. Not healthy looking at all:
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So I guess I need to give them MORE water - although my limited understanding of mushy wilted petioles points toward OVERwatering, not UNDERwatering (is this generally right?)

Here's another wrinkle here. I did not pre-soak the bark or the mix before planting the Caladiums in. I find it easier to work with slightly drier mix than a wet soggy mess I would have had if I pre-soaked. Right after I repotted, for about an hour I soaked the whole pot in room temperature days-old tap water with 2 tbsp vinegar per gallon added in, and then I did it again for both plants at the next watering 8 days later. So I am hoping that the uncomposted bark (the only component I am worried about being hydrophobic) has been saturated - but if I am wrong, then maybe my finger test was misleading me as to the level of moisture in the soil. I doubt it because there is enough composted bark and peat to hold the moisture, but what do I know!

Here is the watering log (oh yeah, kids, tell your friends - grandpa has a log!):
6/1: brought the plants home;
6/6: replanted and soaked both;
6/14: soaked again and fertilized;
6/21: watered and fertilized one but not the other. The watered/fertilized one is doing better than the one that wasn't watered that day.

For fertilizer, I useed weak Foliage-Pro solution (quarter teaspoon per gallon) - and that water also had vinegar added in. (my water is alkaline: http://forums2.gardenweb.com/forums/load/contain/msg0612005017703.html).

Windows in my apartment are west and north-facing, with only an hour of direct sunlight in the afternoon, the rest of the time it's diffused light.

Oh, and what came of the bud, you ask? Here is how it looks now, children:
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I guess it is safe to say we will not see the flower this time around.

In summary, what would you say we learned here today, kids? What did grandpa do right and where did he take a wrong turn?

This post was edited by greentoe357 on Sun, Jun 23, 13 at 8:51