For those of you who don't know, BDSP stands for "Big Damn Screw Pine," and refers to a particular plant I bought in early June 2009. I knew when I got it that it had been in the same pot for at least a year and a half, because it had been in the greenhouse as long as I worked there (and I suspect it had actually been there for at least a year longer than that), so odds were that it probably needed to be repotted.
This seemed particularly likely because it was already nearly four feet tall and probably about as wide, but was only in a 6-inch pot, and had roots coming out the bottom.
So this is the story of how I repotted a plant nearly as large as I was, that was covered in sharp spines, without hurting myself even a little bit, and how surprising that is.
I started out by wrapping the leaves in plastic. This is kinda key for the whole rest of the procedure. I didn't take pictures of the wrapping itself, but I used my Boston fern scrunchie technique, just with an unusually big piece of plastic. Lay the plastic out flat in a rectangle on the ground, lay the plant down on top of the plastic so the bottom of the plastic is lined up with the top of the pot, and then roll the plastic and plant together so the leaves are loosely held up and away from the pot.
The next order of business was figuring out how to get the pot off the root ball. Ordinarily, with most plants, any roots growing through the drainage holes are thin and flexible enough that one can just pull the pot off, and the roots will be fine. In this case, though, the roots were woody and thick --
-- and that wasn't going to work. I did try pulling a little bit, just on the off chance that maybe it would slide, but no. So I cut the roots off with a new, sharp razor blade and slid the pot off that way.
This is not actually ideal, as the fresh wounds in the roots could become infected with bacteria or fungi, leading to rot. I'm not so much worried about that in this particular case, because I didn't have much choice -- either the roots had to be cut off, or the pot had to be cut away from the roots, and the latter option would have resulted in a lot more wounds. The safest course would have been to cut them, then dust the open ends with fungicide. I didn't have fungicide, though, nor did I have powdered cinnamon,1 so we're just going to have faith that it's a large, tough specimen of a large, tough plant, and it either won't be tempted to rot in the first place, or, if it is tempted to rot, it can live without the roots in question.
And as we can see, if the plant has anything at all, it's roots to spare:
Ordinarily at this point in the process, I would try to loosen up the root ball, but in this particular case, the roots were so intertwined in each other, and to some extent actually fused together, that I couldn't. I loosened what I could (mostly just a few little ones from the very bottom of the rootball), and went on.
I don't have pictures of the next couple steps, because I needed both hands for them. Basically what I did was, I got the new 10-inch clay pot, and put soil in the bottom a couple inches deep. Then I set the root ball of the plant on top of that, held the plant upright with one hand while trying to scoop soil into the pot around the root ball with the other, and eventually, through this awkward process, managed to fill in the remainder of the pot with soil. Then I packed down the soil and added more until it was all as firm as it was going to get, set it on the ground, pulled off the plastic, and wound up with this:
You'll notice that although I broke the First Rule of Repotting2 and went from a 6-inch pot to a 10-inch pot, the pot still looks tiny compared to the plant. Ordinarily I advise breaking the FRR only for extremely rootbound plants of the genus Ficus, and even then I say you shouldn't go up by more than four inches per repot. In this case . . . well, you saw the rootball. There wasn't even really any soil3 in that pot. Plus, I was going from a pot that was more or less a straight upright cylinder made of plastic to a substantially tapered pot made of clay: it seemed like I probably needed to go up four inches in order to fit the bottom of the rootball in the pot, first of all, and since the new pot was going to be drying out faster than the old one had, it was probably justifiable to make it a little bigger than I ordinarily would have.
Also I'm not saying any more about it until you let me talk to my attorney.
In any case, the new pot is not, to my eye, yet in proportion with the old one, and the plant is significantly top-heavy, but I don't dare go any larger until I'm fairly sure that the roots have spread through the new soil.
The next step, then, is to water in the plant. Which is done more or less the way it sounds: you water it repeatedly, so the water can penetrate all areas of the soil. And then you're pretty much done.
I didn't get hurt even once, because of the plastic, and I'm getting better at moving the plant around even when I don't have the plastic, so everything seems to be working out so far.
Judging from past experience with repotting a Pandanus veitchii (much smaller plants in those cases, needless to say), the plant is about to have a big growth spurt. The BDSP might do this even more dramatically than they usually do, because not only did it get new soil for the first time in a couple years, it's also going to be spending the summer outside. I like the idea of a growth spurt, though I'm more ambivalent about the prospect of a sharp, pointy plant I can't bring in the house because it's bigger than the rooms are. I suppose we will deal with that if and when it happens.
For the summer, at least, it's going to be sitting just outside the back door. I've always wanted a guard plant, and the Euphorbia grandicornis isn't big enough yet,4 so this should be nice for me. Unless I need to get in or out of the back door, I suppose. [thoughtful look] But that almost never happens. And if the BDSP needs repotted again in September, then I can blog about that process as well.
1 A number of people at Garden Web swore by powdered cinnamon as a superior, or at least more readily available and less dangerously toxic, antifungal for all kinds of purposes. This makes perfect sense to me, as cinnamon bark has to have something in it to keep it from rotting in its native Sri Lanka, which has a tropical climate with annual monsoons, hurricanes, or whatever: this, obviously, is very conducive to rot, so any intelligent plant would have to have something antifungal with which to protect itself. It doesn't hurt that cinnamon smells way nicer than your average fungicide.
I would use cinnamon as a fungicide except that we don't have any around. Neither of us cook. Or, well, the husband barely cooks, and I cook not at all.
2 (The new pot shall be no more than two inches wider than the old pot.)
3 I'll stop here for a second and wave to the pedants who are scrolling down the page to find the comment box so they can point out that I don't use soil, I use a soil-less mix, and that the two things are different and I shouldn't use the word "soil" here. Hi, pedants. I know there's a difference, and when there's a good one-syllable word for soil-less mix, then I'll call it that. But I'm not going to type out "soil-less mix" or "growing medium" or "potting soil" every time I have to mention dirt. (Aha! say the pedants, what about the word "dirt?" It's one syllable, is it not? Well, yes, it is, but there are pedants who will get on one's case for using the word "dirt" too, because of course "dirt" is just the word we use for soil that's in an undesired location, and is therefore unnecessarily pejorative.) You can't win against a dedicated critical pedant, so I am electing to skip past the whole thing saying "la la la, I can't hear you!" rather than do a search-and-replace of "growing medium" for "soil." :^P
4 The Euphorbia tirucalli actually might be, but, a) it's kind of top-heavy so it would be hard to keep it upright for the summer, and b) I personally am actually kind of afraid of the Euphorbia tirucalli. So we don't ask it to go places or do things.