dendrobium potting medium
 

Hi all!

what kind of potting medium is best for dendrobiums? All the label says is dendrobium orchid and the flowers have already fallen off. Currently it is in tight sphagnum moss. Do dendrobiums like more water than phalenopsis? There is also a special potting medium specifically for dendrobiums at the store.

thanks :)

tasha

Interesting question and the answer depends on your growing conditions and whether you like to water...or not. Dendrobiums are capable of growing in all types of media. Ive seen prize-winning specimens in moss , in bark and everything in between. If $ isn't a factor I would recommend the store dendrobium mix to start with.

The ones I purchased at the local shop were in some strange mixture of bark and what seemed to be sphagnum peat...way too water retentive for my taste. I have repotted them in pure bark, part of the original roots died (I suppose they were used to those much wetter conditions), but it has since produced a carpet of new healthy roots in the pot, new canes have emerged and growing very rapidly, they seem very happy in pure bark. I have Dend. nobile and Dend. biggibum (also known as Dendrobium Phalaenopsis or denphal)

I find (overall) that they like more water. If you could get it identified the answer could be more accurate.

There are so many different species of Dend that this question doesn't make sense unless qualified by type or species.

If you do have a photo of the flowers (or google it) please post it. I suspect what you have is a nobile.

Picture
 

Hello,

As requested the picture. But as I said before, all the flowers fell off before I bought it.

apologies i uploaded the photo here. i don't know how to operate my mac. :lol:

Thanks!

All plants like "more water"! Water is the driving force for growth.

I have to think that our - and I DO include myself - misinterpretation of our observation that some do not is because the rest of our growing conditions don't work well to permit the plant to take advantage of it.

I could be wrong, but it looks like some type of Dendrobium phalaenopsis to me.

Do the canes have little black hairs on them? The photo is not very clear. The nigrohirsute types do grow under pretty much the same conditions as the phalaenopsis type - warm, no winter rest.

No they do not have little hairs on the canes. Sorry, i tried scaling the photo down and I guess it took away some of the detail. I'll try to take another photo tomorrow.

Yeah, please don't make it so we need a magnifying glass, some of us wear bifocals already :)

Haha! Sorry.

Here are my hopefully improved pictures of my mystery dendrobium.

Many thanks!

Tasha

I really can't tell if it's a phal/biggibum or nobile type dend, anyone else?
Though my feeling is that for media, it should be basically a well-drained medium coarse mixture (and/or packaged for dendrobiums). I've bought packaged mixes from repotme.com and orchidsupply.com, but they're certainly not mandatory.
Point of fact, is that with most orchids you can grow in most any media, just with care to culture. Easiest though (in my opinion) is a coarse mix with lots of air holes, which you soak on each watering. Then of course there are hydro-solutions (which I've never used).
I really like the repotme.com slotted orchid pot, it maximizes air flow well and it seems roots flourish in it.

That looks like a den. phal type indeed. If you bought it in a store rather than a nursery it is probably some kind of hybrid. As mentioned before, it won't need a winter rest. Dens generally like more light than phals, and most dry out faster too, though phal types tend to do so less than e.g. den nobile or the australian dens.
(At least, that goes for the hybrids I have)

I have my phal-type hybrids in bark or coco coir mixed with bark. I used to have all of them in the latter medium, but some of them apparently found that to be too wet and I had to repot them after root rot issues. Some others are still in that bark/coir mix and do really well. If you do put them in bark, water them more often during the growing season (i.e. when they are growing new canes) than you might do with your phals. Conversely if you put them in a water retentive medium, check carefully if the medium does not stay wet between waterings.

Edit: I see there is some confusion in the post above me - the reason for it likely being a den phal-type is due to the placing and growing direction of the flower spike. Even though it is empty, it can still be seen that the spike grew only at the very end of the cane, and it grows straight up. It's definitely not a den. nobile because these have many short flower spikes below their leaves. This does leave a large number of other options, but as there is no specific name on the label it is likely a popular plant sold to retail stores and the like. Many of the other den types with this trend of spiking are rarer, mostly sold in nurseries only because people specifically look for them, and many have flower spikes that tend to 'droop' over and not grow straight up like that.
Not saying that I'm 100% sure, but it is likely for those reasons this is a den. phal-type hybrid. (Unless ofcourse you bought it in some kind of special orchid store, though in that case I would be very surprised it doesn't have a more specific label)

Yes, you're right...been a long time since I grew nobiles, not having the facilities to give them their winter cooldown.

I got it from Lowes :)

Thanks you for your help!!

Tasha

By the way, maybe it is the perspective of the photo but looking at that first picture - is that what all of the medium looks like, or is that some kind of top dressing? Those bark chunks look huge, you will need to water very often in summer if you keep it in a medium like that because it will dry out very fast. The only orchid I have in bark that large is a den. x delicatum, which grows on rocks in its natural habitat and generally likes to be out in the rain (real or man-made) in a very fast drying medium.

You might want to be a bit careful with just getting whatever a chain store sells as "orchid X mix". My local garden centers sell orchid mix with a phalaenopsis pictured on the package that contains grain-like fine bark. If I put a phal in that mix it would likely suffocate.

^^

@dbarron No worries, that is why we are all here to chip in.

Not to worry, I will repot this den into a medium bark mix. That is what it came in. It has bark on top and packed in sphagnum moss underneath.

Ah, I see. Kinda weird to top spaghnum with bark, what kind of sense does that make...

Anyway, good luck with your orchid!

thank you all! :D