It was always my intention with this blog to show more than just pretty flowers, because that isn't going to educate anyone, least of all me, so I thought it might be time for a blow by blow account of the repotting process. This will serve as a reminder to me of both what I did and when I did it, and it might also help any of my readers who are faced with the daunting task of accommodating a beast of a plant that has put on frankly more growth than is good for it.
I expect there a lot of people who think Coelogyne are nice small manageable plants that will fit comfortably on a window sill. Some species are like this. However, Coelogyne Green Dragon (and both of its parents) are like the big thuggish older brothers of these nice well-behaved plants. Many members of Coelogyne get rather large. I got my division of Green Dragon from Burnham Nurseries a year ago from their special plants list which they send out just before Christmas every year. It wasn't a cheap plant, but considering the proportions it grows to it probably isn't any more expensive gram for gram. Coelogyne Green Dragon is a hybrid between the species C. massangeana and C. pandurata. Both parents are large growing species from lowland jungles that bear long pendulous racemes of flowers with their new growth. Utterly beautiful when in bloom, but a bugger to accommodate.
Anyway, I've gone a bit off topic. The point about this hybrid is that it has rather taken after its C. pandurata parent in that it has quite a long length of rhizome between its pseudobulbs, meaning it has a tendency to climb out of its pot after a year or two.
As you can see, I had to do something with it this season, and since the new growth has just started to produce roots, there is really no better time. You can see the new growth well overhanging the edge of the pot, and you also get some idea of the size of the plant in this photo, remembering that it is a relatively new division at just over a year old. I thought long and hard about what I was going to do with it once I got to repotting time, and finally decided that a basket was the answer. Most growers grow large and specimen species like this.
I got the necessary articles together; I already had a 16 inch basket lying around as it happened. In a rare moment of forethought, I took the chain off as I won't be hanging this plant (it'd pull the ceiling down!). I also had a handy basket liner stashed away (as you do!), as well as ample supplies of Melcourt potting bark, so it was all systems go.
The sharper eyed among you might notice the deliberate mistake here. I may indeed have ready a 16 inch basket as a new home for my treasured plant, but I failed to notice that I only had a 12 inch basket liner. Fail. So after some dummy chucking and trips to the garden centre, I was finally ready to do the business. I managed to get the plant out of its pot after some wrestling, and I notice it has developed a nice root system which is always good news. Nice and well developed, but not root bound which would have caused problems of its own.
Notice also that the plant is very damp indeed. My experience of pretty much all Coelogyne is that they really don't like to dry out, so watering is frequent, and this appears to be the moisture level that the plant wants at all times. Also, damp roots are much more pliable and therefore less likely to get damaged during repotting. It is obvious from the size of the older pseudobulbs (right in the middle of the photo) that this plant still has some significant growing to do before it reaches its full potential. I work on the ground in a gravel bag tray to catch stray bark chips, though I suspect normal people might do this on a bench. As you can see, the basket liner is just a bog standard cheap one. Its purpose isn't to trap any water (in fact, the more water it lets through, the better) but just to stop the bark chips from falling out of the basket and help to contain the roots.
I removed the very oldest backbulb as it was getting in the way and had no roots of its own in any case. There's always the chance that it'll sprout new growth, but I frankly doubt it. With semi-climbing plants like this one it is a good idea to try to partially bury the older pseudobulbs so that the base of the new growth (where the roots emerge from) is in contact with the potting medium. The oldest part of the plant should be at the edge of the basket (or new pot) so the new growth has the maximum amount of space to grow into before the plant needs disturbing again.
If this were almost any other type of orchid than a Coelogyne, I would probably recommend using coarse bark chips for a plant this size as finer stuff holds more water in the centre of the pot/basket and a lot of orchids won't like that. However, this being a water-pig Coelogyne, I have used medium bark, because I want that extra bit of moisture retentiveness (I could have added perlite, but I prefer not to as I find it rather unpleasant to work with; when dry it is dusty and when wet it sticks to my fingers. I have also heard that it can hang onto nutrients which will burn the roots eventually).
Now I slightly break the rules here because the standard advice is to use fresh potting medium each time one repots. I'm too tight to waste materials that, at least to my mind, are still perfectly good. Provided there aren't any root problems (which there weren't), any problems with pests (which there weren't) and the bark chips haven't started to break down (which they hadn't), I see no reason not to re-use them. If in any doubt, they can be put into a cool oven for an hour or two to kill any nasties, but that wasn't necessary on this occasion. Of course, if you are changing potting mix, you shouldn't mix them, but I'm using the same bark chips here.
I'm always careful to work the new mix around the roots so I don't leave any air pockets. It is also a good idea to give the whole thing a good few knocks (I lift a couple of inches and drop a few times) as this will help to settle the potting mix around the roots.
The end product. As you can see, the new growth is just in contact with the surface of the potting mix and there is plenty of room for the plant to grow out for a couple of seasons before I need to tackle it again by which time I expect I'll need a crane to lift it! Its new growths already seem to be larger than last year, so I expect it will settle down into its new home very quickly. The basket will be stood on top of al large pot so I can still keep it on the benche. The plant didn't bloom this year, although this isn't unusual for new divisions so I expect it'll bloom sometime around Christmas. It is always a waiting game, with orchids!
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