Dendrobium: fast new growth but old canes wilting/ is it Nobile?

[stefpix]

Hi

I got some Dendrobiums on sale at Lowes for a dollar each after they bloomed.
they are doing well except one marked as Den. Hollywood.

There is a new growth growing fast but the 2 old canes dropped the leaves and started shrinking.

The new growth seems to be about to put out a bunch of new roots but the 2 old canes seem to not growing any roots.
I wonder if it may be a Nobile type hybrid. even if it seems to have a cut flower stem at the apex of the cane

also some of these Dendrobiums have leaves only on top of the canes but one Den Pegasus Pink has leaves all along the thick tall cane [also growing new small canes].

I asumed these big box store Dendrobiums are for the most part hot climate types that need no winter rest - but I wonder if some of these may be a different kind that needs a dry winter rest

stefano

[catwalker808]

From their appearance, the plants are not nobiles. The canes look like either spatulata (antelope, rabbit ear) or phalaenopsis type dens. If they were at Lowes, they are probably phal types, which do not love to experience climate change when budding or blooming. Especially being in a store for 3 weeks.

That is why the old canes have dropped their leaves. The roots of the old canes were also probably dead in the store. They will not grow new roots, except (as you notice) in conjunction with sprouting new keikis (which have the new roots). When in this condition, the old canes only serve as a source of food and aerial keikis (further up the canes) may also emerge.

[stefpix]

Thanks -
I thought they would be phal types - but wonde why some have leaves only on top of the cane and others all along the cane. I got 4 and only the D. Hollywood showed decline when producing a keiki. the others look fine - and do not look like they woudl decline any time soon and actually are producing more keikis.

in the case of the one that is drying up - when should I separate the keiki from the original plant? and how long would take for a keiki to grow and bloom?

[Blueszz]

Originally Posted by stefpix

Thanks -
I thought they would be phal types - but wonde why some have leaves only on top of the cane and others all along the cane. I got 4 and only the D. Hollywood showed decline when producing a keiki. the others look fine - and do not look like they woudl decline any time soon and actually are producing more keikis.

in the case of the one that is drying up - when should I separate the keiki from the original plant? and how long would take for a keiki to grow and bloom?

If the keiki is close to the medium I wouldn't remove it from the older canes. These canes still can provide nutrients for newer growths. Once you remove the keiki from the mature cane, it will develop much slower.

Nicole

[stefpix]

Thanks - no intention of removing - just put in a smaller pot and base of the keiki closer to the medium...also put outside on window ledge rather than under shoplights

[quiltergal]

Technically that is not a Keiki. This type of Den, like most Dens is sympodial. It sends out a tiny little rhizome, then starts to grow a new cane, then the new cane will grow new roots. All those canes together are really one large plant connected by rhizomes. The plants do better if left intact as a single colony. The newer canes will use the older ones to draw moisture and nutrition from as needed. When the cane is all used up it will turn yellow and die.

[Liz F]

Really glad for this thread. This was my question as well. Here are mine:

[Blueszz]

Hello Liz,
welcome to OB!

What exactly is your question? Do you want to know if your Dendrobium needs a cold winter rest or not? For identifying orchids and problems it's better to upload a picture that shows much more detail ---> a larger pictures. Also if you have a picture from the blooms, it could be helpful telling you what kind of Den. you own.

Nicole

[Liz F]

Hello Nicole, thanks for the welcome!

No question really, just expressing that I also had Stefano's question on new growth & shrinking canes. And you guys on orchid board had my answer.

Sorry for the tiny photo. I received this plant (with a few others) after it had bloomed, so I'll have to wait to know exactly what they are.

Thank you!

[stefpix]

for sure my kingianum is a slow grower... maybe i got a runt division or something... I can see some growth but tiny and slow - and canes are a bit shriveling / yellowing...
maybe this summer has been not warm enough for enough time -

My Den phalaenopsis i bought for a dollar on closeout are all sprouting new canes - not as tall as the old canes - but i really can see growth.

MY D k is potted in a 2.5 " clay pot with lava rock and a mix of bark, coal, gravel, perlite. watered once a week or 5 days - but now I am wondering if i should wate every other day or at least mist the roots...