Why I think bark is the worst media for orchids

[Orchid Whisperer]

It all comes down to whether bark is good for YOU, or isn't. That depends a lot on your growing conditions, and also your growing practices.

Bark isn't working for you ? Great, find a medium that does work for you and your plants.

Bark works great for many of my plants, not so much for others. I use whatever works.

[Keysguy]

Isn't that the truth!
That's what this game is all about, isn't it? Figuring out what will work for you and then keeping 1 step ahead of the grim plant reaper?

[Leafmite]

Other reasons I do not like bark:
It seems wasteful. From where does the bark come? Are trees being killed just for the bark? Do I really want to buy more bark every year or so?

What if the tree from where the bark comes had a virus? Will that infect my orchids?

In nature, orchid roots get established on the tree/branch/rock and the orchid tends to stay there. With bark, one must disturb the roots when the bark has decomposed. If one has ideal conditions, the orchid can re-establish quickly but if one does not, it might take some time before the orchid is happy again. Because the bark is changing as it decomposes, I always found it difficult to know how often to water.

I absolutely hate picking bark off of roots...just hate it.

With bark, my orchids always did great during the summer, when the bark was new but, by February, the bark had decomposed enough that the roots began to rot and my orchids had to start over every spring.

I do better with NZ sphagnum moss than with bark. Most of my orchids are in red lava rock and basket pots. A few are mounted.

[ChrisMalaga]

I'm not sure if trees are cut just for the bark, I like to think they use the bark of trees that they cut for different reasons (it would a too big waste to throw away the wood), but your point on disturbing roots is another reason to avoid bark for me!

Unfortunately also sphagnum has this problem, especially with very fine roots, it can be a pain to remove and sometimes impossible to do so without making some damage.

Leca, scoria and other inorganic materials clearly solve this problem, as you can keep those pieces attached to the roots without any concern. This can also mean that a Cattleya will suffer definitely less and lose less roots, when I grew Cattleyas in bark, repotting also meant losing the vast majority of old roots.

[Ray]

Originally Posted by Leafmite

Other reasons I do not like bark:
It seems wasteful. From where does the bark come? Are trees being killed just for the bark?

I cannot speak for the Besgro people, who farm their Pinus radiata trees, but generally speaking when trees are commercially felled, the entire thing is used. I suspect the bark is probably the least valuable part.

When I lived in SC, I had a neighbor that ran a tree lot for a major corporation. They prided themselves on the fact that only 3% of the tree went unused, and that was the water that evaporated from it as it was processed.

The bark and layers immediately under it are a significant portion of the bagged potting soil one buys for terrestrials.

[isurus79]

Chris- I'm curious about why you want even wetness throughout the pot. Some nooks and crannies in the pot will dry faster/slower than others no matter what media you use. The plant roots will adapt, as they do in nature (which is full of nooks and crannies)!

Tree bark is a by-product and is not the primary purpose for cutting the trees. Orchiata has a pretty good video about their process:

[beachgirl]

It has alot to do with your environment, in my opinion, as to which medium will work best for you. In South Florida, where it's hot and humid, my orchids (mostly phals) were suffocating in sphag and regular bark was breaking down too fast leading to pathogens.
I saw a video which suggested layering a pot with a few strands of sphag on the bottom, a layer of charcoal, then orchiata with some perlite for the middle section, and a few more strands of sphag on the top to keep it moist. This works perfectly for me. But I will never go back to lesser quality bark. I have not seen the regius bark which some people like though, so I don't know about that. The charcoal and the orchiata seem to help with pathogens. I soak the plants in water twice a week, but I don't use different water for each unless the plant is having problems. It seems to be working.
Without the air space this bark provides, my roots were suffocating. I tried leica S/H but didn't have the luck other people have had, although I might give it another try.
Anyway if you were ever to try orchiata, you might find you really like it. I use the classic size, which is perfect for most of my phals. It is a little more expensive than the norm, but I get mine from an orchid supplier and its relatively cheap. It doesn't break down fast like others and I also don't have to repot as quickly so I think it ends up being the same cost.
I do not try to wet my media as you describe you do. The reason I soak for a half hour is for the phals' vellum to absorb max water. I put several in a large container of rainwater at a time to soak. I can usually see the roots through a clear pot and at the top of it, so I can tell when they are bright green or silvery and need water.
I have problems using this system with oncs and other finer-rooted orchids though for the visibility issues you describe and because those roots don't have the absorption mechanism phals do. I have not found my ideal media yet for those. But for phals, I love the "orchiata sandwich."

[ChrisMalaga]

Originally Posted by isurus79

Chris- I'm curious about why you want even wetness throughout the pot.

In my experience, uneven wetness has been a problem for many of my orchids, especially those that are not well estabilished and those that don't have an extensive root system. A Cattleya won't probably abort new roots if the surface is too dry (edit: this is also true for leca although not so much in my environment -> can be solved using pebbles on top), but many others will. You can fix this a sphagnum layer, but this doesn't make bark a better material, it still has many faults which must be fixed with something else. Moreover, some roots will be in touch with wet areas, while others won't, this is also connected to the fact that knowing when to water is tricky: I've seen that the core of my pots can be wet while other visible areas are bone dry. This has led me to overwatering issues many times.

---------- Post added at 10:53 AM ---------- Previous post was at 10:40 AM ----------

Originally Posted by beachgirl

It has alot to do with your environment, in my opinion, as to which medium will work best for you.

I'm totally sure about this. Every environment is different, also, everyone has different watering techniques and different orchids.

But still, many of the faults bark has can be true in every enviroment: is it wicking? Does it offer even moisture? Does it make it hard for pathogens to live? I think you can live in any place of the world and have a better experience with LECA, scoria and sphagnum (or even mounting), only the frequency of watering will change: if you live in the desert you may not want to grow your orchids mounted as it may mean you have to water them 2 or 3 times per day, but if you can provide such regime, I don't see any downsides.

I read about S/H and personally I prefer self watering, which is similar but doesn't allow any direct contact between roots and water. I can't say I'm an expert about self watering because I started with this just a few months ago. Malaga has a climate between LA and Miami, I think, although it doesn't rain as much as in Florida here. However, being close to the warm Mediterranean with some high hills behind, humidity is usually around 70%. In winter, whatever is not placed in direct sunlight, doesn't dry ever.

[Ray]

You are still growing semi-hydroponically; just a different variant.

In the S/H setup without inner pot, you do not put the roots into the reservoir, as they will drown. They will, however, eventually grow into the reservoir, and that's perfectly fine, as they adapted to being submerged as they grew.

If your self-watering pots are the kind with mesh- or slotted inner pot and a gauge, the roots will eventually do the same.

[thefish1337]

I've gone to mixtures that are 80-90% pearlite, leca, stalite and charcoal and 10-20% bark. I don't know why but a little bark seems to perform best for my conditions.