Dendrobium leaves turning yellow & falling off

[KCR]

I purchased this dendrobium this spring while it was flowering. It finished flowing and I started watering and fertilizing it and it was thriving - growing new leaves and new little white roots. Then a spike formed and now I have 9 buds on the spike with one bud open & another one about to open. However, all the other plants and leaves in the pot are starting to turn yellow and die. I don't know what has happened. I have attached a picture of the flower and also what is happening to the leaves.
I checked the web and they say that there are so many differnt types of dendrobiums that I have to first find out what kind it is in order to know how to care for it. What is written on the stick is: C312 D Jacq Concert x compactum. I have not been able to find anything like this on the web.
Can anyone can help me find out what I am doing wrong and what kind of dendrobium I have? Thanks!
Karin
DendrobiumFlower.JPG

Dendrobium_yellow_leaves.JPG

[brookn]

It looks like it could be in need of a repot. Sphag sours easily, and it also retains a lot of moisture, you may have rotten roots. Here are some links for you.

AOS | Dendrobium

http://www.orchidgeeks.com/forum/new...f-orchids.html

[Rishad Kalarikkal]

I think it is natural...mine used to shead leaves....any ways ill leave it to experts...

[jerrymeola]

When leaves yellow that many and that fast it is damaged roots. It could be something you did or the grower did before you got it, or it can be natural aging accelerated by moving it to you home.

It is a Den-Phal type of Dendrobium. These are the most common type. Something I have never mentioned before is that the genetics of many hybrids tend to bare canes. These plants were breed for cut flowers and the appearance of the plants was unimportant.

As to your plant the new growth looks very good. It appears to have been the cane that flowered. This makes me think that the reason is the third possibility, that is, that it is aging accelerated my moving.

Potting medium for Dens is normally small to medium bark mixed with perlite and maybe some charcoal. You can grow them in sphag but most hobbyist do not realize the sphag packs down heavy over time. It needs to removed and loosened periodically the same way bark must be replaced with fresh bark every two years.

Check to make sure it is all sphag. Sometimes sphag is placed over bark to make it look better for sale. This can be very misleading for hobbyist since the sphag dries fast on top and hobbyist re-water too soon before the bark dries. Watering too often will lead to rot.

You can leave it in sphag if you want to be able to ignore the plant, but if you like to pamper it and water more often, then switch to bark.

[digitalgate]

you have a mini dendrobium. Most likely your plant root already rotted. Sphag media is very difficult for novice. Like jerry said, change to charcoal(or bark) mixed with sphag would be easier for you.

[virgil]

also this time of year if Den. gets in a cold snap sometimes below 50% the leaves will start to drop, repot and warm up is the cure.

[KCR]

Thank you to everyone for your help. And thank you for directing me the information about skewer use for watering orchids. This information is GREAT - Thanks Cynthia! I have been soaking new potting medium and will repot my dendrobium. I will tell you all how it's going in a few weeks.

Thanks again to everyone for your help.

Karin

[davetheorchidaddict]

When any of my new purchases come in spag I repot them as soon as they get home. I will pull them out of the spag as soon as I get there and leave them on the bench until I can get back and repot or mount them after all they are air plants and will survive out of the pot.