I think I figured out the whole Dendrobium thing.
I have the experience of having had trouble properly hydrating my Oeceoclades calcarata to thank for this.
The story goes. Oeceoclades calcarata is a lithophytic orchid, and I grow it just like that. However, I don't grow it in a very large pot.
Keep in mind Oeceoclades calcarata is a giant sized orchid that can reach 9 ft tall with spike. The largest pseudobulb on mine is about 4 inches tall. Some of the smaller growths have leaves that are about a foot long, with the smallest pseudobulb at between 1 1/2" to 2" tall, having leaves that are about 8" long. I think I have a total of 5 growths with 3 of them being pretty large.
After about a year of growing it in a 6" pot, I started having problems keeping it hydrated.
When I was about to repot it into an 8" pot, it turns out that the roots were starting to crowd the 6" pot.
Roots crowding the pot meant that the orchid was drying out the medium much faster than the medium could retain the water. Therefore it had problems keeping the pseudobulbs plump.
Once in the larger pot, the Oeceoclades calcarata pseudobulbs plumped right back up in a few days.
The Dendrobium's roots when it crowds the pot may be doing the same thing. Namely, absorbing the water from the medium faster than the medium can retain. Which means, the medium is drying out faster. Hence no root rot in Dendrobiums as a result of crowding the roots in the pot.
__________________
Philip
Last edited by King_of_orchid_growing:); 03-09-2011 at 09:28 PM..
|