# I have trouble growing orchids in bark...



## The Orchid Boy (Oct 3, 2012)

I grow all my phals and my masdevallia in pure sphagnum moss and my paphs, cattleya, and potinara in a mix of about 1 to 1.5 parts sphagnum, 1 part medium or fine bark, and .5 parts charcoal. The only time I can grow in bark is in clear pots. 

I recently got a large sanderianum and a graxtrianum seedling. The repot date on the sanderianum is April 2011 and the graxtrianum was repotted in August 2012. The are both in a bark mixture. Any tips for growing in bark or is it ok to repot them into my own media? I don't want to repot them if it is going to stress them out too much. 

Does anyone else have trouble growing orchids in a bark mixture with no sphagnum or other water holding material?


----------



## NYEric (Oct 3, 2012)

This is a factor of your relative humidity, and your watering frequency. I would always use sphagnum (especially live moss) in any mixes.


----------



## eggshells (Oct 3, 2012)

I can't keep medium bark moist all the time especially in the summer. Which is good for my Cattleyas. My paphs not so much.

However, I have good success with fine fir bark (seedling grade) along with large perlite and horticultural charcoal.


----------



## The Orchid Boy (Oct 3, 2012)

I do have low RH. I wish it was higher but I'm afraid if it is too high, the paint will start peeling off the walls of my bed room.

I have trouble knowing when to water. Is there any way of telling beside poking something in the media? What about my two new paphs that are potted in bark? I'll probably be able to manage the gratrixianum which is planted in seedling bark, but what about the sanderianum?


----------



## ehanes7612 (Oct 3, 2012)

i grow mine in bark/perlite mix, with pots that have side holes so that water doesnt get trapped in the bottom...and i also have high humidity (70 daytime and 80-90 at night)


----------



## Paph_LdyMacBeth (Oct 3, 2012)

Masdevallias like to be moist all the time so moss works great for them providing you have sufficient air flow. 
There's really no hard and fast rule for potting medium you just have to pay attention to what your plants need and what its telling you. 
I don't see any reason why you can't use your mixture with your Phaphs -many people I know use some sphag with theirs. You just have to be able to pay attention to your plants. 
Also, clear pots are a great idea when experimenting with new mixes because you can see what the roots are doing without having to disturb the plant.


----------



## Cheyenne (Oct 3, 2012)

I I am the opposite, I can't grow things that well in sphagnum. Bark is my media of choice. When you first repot if you do not soak the bark first you need to water pretty frequently till it will hold more water. Also you need to use the appropriate size for each plant and genus, this helps alot. When I firat started growing I used pretty course bark for everything and did not have alot of luck. I also use a good bit of perlite. About a year and a half ago I switched to orchiata and I wish I did it sooner. I love the stuff and find it easier to grow in than fir bark. 
I would stick with the bark at least till you get real familiar with growing paphs. Then start experimenting. Most people are successful with bark. If you try a lot of things and they don't work out then it is easy to get discouraged. I say learn the basics first.


----------



## Clark (Oct 3, 2012)

Same trouble here. It is a vile enviroment for Paphs.


----------



## keithrs (Oct 3, 2012)

There's no one media mix that is an end all.... If you like your mix, use it!

I think I've tried everything under the sun and rarely stick with the same mix for too long. I'm a huge fan of CHC mixed with various things.


----------



## Eric Muehlbauer (Oct 3, 2012)

I find that sphagnum is not a good thing for paphs...breaks down too quickly, getting very acidic. I won't even put it into my mix. The exception is P. delanatii, which thrives in the mix of bark, sponge rock, and NZ sphagnum that I use for my phrags- but I don't keep it as wet. I learned from experience nearly 30 years ago that bark is best for paphs. But bark is variable. Some bark sources are terrible. I once got a big bag of Rexius bark. It was horrible stuff...leaving my fingers full of splinters. Worse, during a hot summer, it destroyed the best paphs in my collection, including tigrinum and a magnificent insigne sanderianum. It was a total disaster...although my phrags loved it. (Then again, phrags love everything...except CHC.) Sequoia bark is a much better, more stable brand, and Orchiata seems like it might be the best. I always add a lot of sponge rock, even with Orchiata which is supposed to be used straight. I use small grades of bark, which hold moisture better, but re-pot after a year.


----------



## Stone (Oct 3, 2012)

The Orchid Boy said:


> I do have low RH. I wish it was higher but I'm afraid if it is too high, the paint will start peeling off the walls of my bed room.
> 
> 
> 
> ...


----------



## The Orchid Boy (Oct 3, 2012)

Cheyenne said:


> I I am the opposite, I can't grow things that well in sphagnum. Bark is my media of choice...
> 
> I would stick with the bark at least till you get real familiar with growing paphs. Then start experimenting. Most people are successful with bark. If you try a lot of things and they don't work out then it is easy to get discouraged. I say learn the basics first.



I would stick with bark but I haven't had any experience with just bark without sphagnum moss. All the orchids I've bought came in moss or I repotted them right away into my mixture. I have a Paph. Magical Venus planted in a bark/sphagnum mixture and I crushed up some lime stone and put powder and small pieces in the media and I also water it once in a while when I rinse out milk jugs. I do both these things to add more alkalinity to the mix and to counteract the sphagnum. 

Could I repot the gratrixianum and sanderianum or not? The reason I ask is because the gratrixianum was jus repotted in August and I've heard sanderianums don't like to be repoted too much; it was repotted in April 2011.


----------



## Rick (Oct 3, 2012)

Maybe you should consider semi-hydro?

The more I poke at the over feeding, EC pot management thing, the more I find that orchids (even paphs) can have constantly emerged roots, and not experience root rot. I still can't get over the pics of a semi hydro grown bellatulum from a few years back. I've only had tigrinum and barbatum growing SH and they did fine, but now going low K they are doing better while switched back to pots and baskets with more conventional substrates.

Since I started monitoring EC, I'm feeding less, watering more, and roots just going to town. Regardless of bark, moss, or chc.

I think sanderianum would be a great candidate for SH since it lives on dripping wet limestone cliffs. Roots exposed to air and elements.


----------



## The Orchid Boy (Oct 3, 2012)

I might have to look into hydroponics more. I've always thought about it. There's a small hydroponic store in a 'big city' about an hour away. I just looked in the windows once and they had all sorts of neat things; all kinds of fertlizers, media, pots, and grow lights.


----------



## Cheyenne (Oct 4, 2012)

If you wanted to repot the sanderianum I think it would do fine. But I would not add sphagnum to the mix. Especially a mature sanderianum, they should stay in there pot (ideally) for about 18 months. That is to long for sphtagnum, it will break down and affect the rest of the mix. I would soak the bark mix for 24 hours to make sure it will hold water. 
After you repot you could always use the bamboo skewer method. I used it when I started growing to get the hang of when the bark dried out. Just keep some skewers by the pot and when you want to check stick it in the mix for a few min, pull it out and see if it is wet and hold it to your skin. Also compare that to the weight of the pot. I would also try to find a clear pot. If your sanderianum came in pot it is not an urgent matter to repot right this minute, so get the right pot and the right materials first. Other people may disagree but I would not jump into things like semi hydro with multi floral paphs right away. I found with s/h you need very good water, so unless you have RO water on hand it will lead to problems. My tap water accumulated to much in the mix very fast. I also used spring water from the store and it did the same thing just slower. 
If the gratrixianum was just repotted in aug I would not see a reason to repot it but they are alot more forgiving so you could repot that too so they are in the same mix. One more thing. If you do repot the Sanderianum, whatever mix you pic make sure to give it good drainage. I put the chunkier parts of the mix on the bottom to ensure there is good air at the roots.


----------



## Rick (Oct 4, 2012)

The Orchid Boy said:


> I might have to look into hydroponics more. I've always thought about it. There's a small hydroponic store in a 'big city' about an hour away. I just looked in the windows once and they had all sorts of neat things; all kinds of fertlizers, media, pots, and grow lights.



Make sure you talk to Ray first (he's a ST member). He specializes in SH growing of orchids SH.


----------



## paphreek (Oct 4, 2012)

Lots of good advice has been given here, but after listening, trust your own instinct about what is needed to grow your plants. From listening to what you have said, it sounds like some sort of moisture retaining component is needed in the mix for your conditions. Moss has worked for you in the past, but tends to break down fairly quickly. As an alternative, you could try adding bit of CHC (coconut husk chips) to a bark mix. The CHC will absorb some extra water and help maintain the proper amount of moisture around the roots.


----------



## The Orchid Boy (Oct 4, 2012)

I was looking in one of my orchid books and it mentioned and showed a picture of some inorganic green horticultural foam. Anyone know if this works or where I can find it? Could I make it by cutting up clean sponges or something?


----------



## eggshells (Oct 4, 2012)

I'm a little bit worried that it might take quite some time to dry if you do that. I feel that my environment is similar to yours. Dry and humid in the winter. 

I use fine bark, charcoal, and perlite equal parts. In addition to that. I used small lava rock and a mix of ground oyster shells and dolomitic lime when I mixed the substrate. I also put some top dressing on it which works out their way into the pot every time you water.


----------



## Shiva (Oct 4, 2012)

Through the years, I tried every media I could find for growing orchids and was never fully satisfied until I tried the Aussie Gold Mix. I'm not saying it's the best media ever, but it works very well for me. 
I have 250 plants growing in it, and the only plants I lose from time to time are due to erwinia infection. There are some phrags and paphs that do sulk for a while but no media can work for everything we grow. They eventually come around or the weaker ones die. 
You have to know how to use it however. For phrags, you have to water often and make sure all of the media is watered. If you only put water in the corner of the pot, it will tend to go straight down and out without wetting the rest of the mix. That means going around the base of the plant with the water. Paphs like to dry out a bit more but again you have to water all around the base of the plant. For other plants, you also have to respect their dry season or the right time to repot. Not too much fertilizer either since it tends to stay in the media too long. Water with pure water or RO water two or three times before you give the plant a weak solution of fertilizer.
I use the paph and phrag mix for most plants and I add more diatomite for bigger plants. The really big phrags are grown in a mix of Aussie Gold and medium size diatomite rocks. Some are grown straight in medium diatomite rocks. I also found that AirCone pots are a perfect match for Aussie Gold Mix. The very large pots I also use have a reservoir of water at the bottom. This is very much like semi-hydro culture with diatomites.
There are no bugs in the media, since they have nothing to eat, with of course the exception of mealies, who feed on the plants themselves. They are under control but if anyone knows of a way to get rid of them for good, without killing the plants, I would very much like to know about it.


----------



## eggshells (Oct 4, 2012)

Shiva said:


> They are under control but if anyone knows of a way to get rid of them for good, without killing the plants, I would very much like to know about it.



This takes a lot of work but best is to repot everything with fresh media. Rinse plant well through running water. Remove all dead leaves as they can be hiding in leaf axils. And spray with Safers Endall II with reckless abandon repeating every week.

Forgot to say follow the label


----------



## NYEric (Oct 4, 2012)

Is anyone else wondering
.
.
.
.
.
.
.
.
What the heck is a milk jug!?


----------



## Shiva (Oct 4, 2012)

eggshells said:


> This takes a lot of work but best is to repot everything with fresh media. Rinse plant well through running water. Remove all dead leaves as they can be hiding in leaf axils. And spray with Safers Endall II with reckless abandon repeating every week.
> 
> Forgot to say follow the label



That's what I'm using now, but I was hoping for something like a neutron bomb for mealies.


----------



## NYEric (Oct 4, 2012)

Mealies are tough, even after I think I got them all I find some later. I found patches of them when the temps started to drop here. Nothing like swabbing them with 91% isopropyl alcohol! Die plant suckers!!


----------



## eggshells (Oct 4, 2012)

Endall is kill on contact so you may have to be really vigilant. When you see something spray right away. I tend to coat the whole plant with that concoction. Especially the hard to reach areas. I dont have any mealies as i tend to send back the highly infested one to the seller. Major concentration is the point where bark meets the axil usually.


----------



## NYEric (Oct 4, 2012)

My combo of Merit 75, w/ neem, Dr. Browns soap, and alcohol seems to get them for a while but I only sprayed the plants; maybe I need to spray the bark also!


----------



## Shiva (Oct 4, 2012)

They remind me of tribbles in Star Trek : born pregnant!


----------



## Leo Schordje (Oct 4, 2012)

Woah, slow down. 

Malachi, the sanderianum is due for a repot. But please don't try a potting mix you are not familiar with on that plant. Use a potting mix you know how and when it will go from wet to dry. 

As I tell people in my talks. You can pretty much grow orchids in just about any mix you want IF you understand how and when to water. I grow in bark based mix, I know a local grower who grows the calcareous loving Paphs, like bellatulum and concolor in nothing but pure New Zealand Sphagnum, and she has keep plants growing and blooming this way for 20 years or more. It is just a matter of knowing how and when to water and fertilize. 

First. Is the mix you are currently using for your other orchids working well for you? If yes, then just repot the sanderianum into that mix. Simple as that. Don't complicate matters trying a new mix on an expensive plant. Also as to the gratrixianum, even though it was just repotted, go ahead and repot it into your own potting mix, so it will be on the same schedule as the rest of your plant. USE THE MIX THAT YOU KNOW WORKS FOR YOU. (not shouting angry, just want to make sure you don't miss my point) I have killed more expensive plants by trying some new '"magic" mix that is supposed to be more "scientific" and the "ultimate" high tech solution to handling a plant with a touchy reputation. In the end, I do best with difficult plants when I use the potting mix I am most familiar with, in part because at a glance I know if it needs water, or if it is time to repot, or time to fertilize. Then the difficult plants grow well for me. 

If you end up with a bunch of plants in a number of different mixes, you won't be able to individually customize a watering schedule. You will have to be able to check them individually every day. Pot ALL your orchids into the same basic mix. Or if you use more than one potting mix. Put all the plants in one mix right next to each other, and all the pots in the other mix right next to each other. Plants in the same size pot and same potting mix will generally need watering on the same day. Make life easy for yourself. Settle on a mix and stick with it. Adjust your watering schedule to the potting mix you like to use. 

Or, if time for watering is in short supply, adjust your potting mix to your watering schedule. This second option is more difficult to work out the details, but once you do it works. 

An ideal potting mix should be one you understand when to water.


----------



## The Orchid Boy (Oct 4, 2012)

I may wait to repot the sanderianum until April or after it blooms. I'll probably wait to repot the gratrixianum until next year. I thought about a mix of medium orchid bark, coconut husk chips, a tiny bit of coir, perlite or small lava rock, and charcoal for the sanderianum. 

For the thrips, have you tried submerging plants in water and trying to get them off?

Edit: Leo Schordje and I must have posted at the same time. I know, sometimes my mind races a million miles a minute, but that is how I learned most of what I know about orchids.

Leo: Do you think I could use sphagnum in the mix (about half or less sphagnum)? If I do use sphagnum, how often should I repot and should I worry about the acidity of the sphagnum and adding alkalinity? Thanks so much.


----------



## Shiva (Oct 4, 2012)

Very good advice Leo. And it's always good to repeat it.


----------



## Leo Schordje (Oct 4, 2012)

In terms of a reality check. I use 3 potting mixes for all 1300 orchids in my collection. Through years of trial and error I have adjusted them to all go from wet to dry within a day or so of each other. This way, the whole collection can be watered on the same day. 

There is nothing magical about my mixes. The first is a medium grade fir bark, charcoal, sponge rock and coconut husk chunk mix, roughly equal parts bark and coconut, and the bark-coconut mixture is 4:1:1 :: bark-coco : charcoal : perlite. This mix is shaken over a window screen to eliminate fines. Then I dampen it and mix, so it is moist when I do my repotting. If I am potting Paphs, I'll top dress with a little sand or crushed oystershell depending on whether the Paph is a limestone lover or not. Sand for the acidiphiles. 

The second mix is the fine version of the first, but I use a 1/2 screen to eliminate the big chunks and a window screen to get rid of the dust and powder. A 2 inch pot of fine mix will dry about the same speed as a 4 inch pot of the medium mix. 

The third I use is straight Chilean Sphagnum moss. I try to pot loose enough that the moss goes wet to dry in the same time period the bark goes wet to dry. 

That is it. I settled in on this pattern after 15 years of trying everything new under the sun often with tragic fatal results. I've been growing orchids for nearly 40 years, and the last 25 or so I have been really happy that with the growth my mix gives me. 

This doesn't mean I never change. As the price of bark went up and quality of bark went down, I experimented on cheap throw away plants and settled on the addition of coconut husk chunks to my mix. It was a year long trial and error, but it worked and I am happy with it. 

There is no reason to use my potting mixes, it is just a FYI about what I actually do. You can grow orchids in just about anything you want, if you know how to water the mix. 

New material I am looking at as an 'extender' that will retain structure, allowing a bark mix to last longer, is shredded rubber mulch. It was on sale at 1/2 the price of bark. I am now testing it to see how it works as a component in a mix. But I am testing on plants that are expendable. 

Hope this helps.


----------



## Leo Schordje (Oct 4, 2012)

The Orchid Boy said:


> I may wait to repot the sanderianum until April or after it blooms. I'll probably wait to repot the gratrixianum until next year. I thought about a mix of medium orchid bark, coconut husk chips, a tiny bit of coir, perlite or small lava rock, and charcoal for the sanderianum.
> 
> For the thrips, have you tried submerging plants in water and trying to get them off?
> 
> ...



I think the mix you described as what you use for your other orchids is just fine. The only addition I would make is top dress the sanderianum with a little oyster shell (1 teaspoonful per 4 inch pot) or use horticultural lime if you don't have oyster shell handy. I get mine from a Saddle and Feed shop, where they carry feed for poultry. Its cheap. 

I have seen my friend Cathy grow and bloom rothschildianum and sanderianum in nothing but New Zealand Sphagnum. It certainly can work, and work very well if you know when to water. And adjust your fertilizer to the mix. 

Again, when tackling a species with a reputation for being touchy to grow, though sanderianum is really not that difficult. It is best to stick with a potting mix you already know how to use. Your original mix sounds fine. 

Thrips. I tolerate a low level infestation until autumn. Every fall the whole collection gets sprayed. I will admit to using pesticides in a manner not consistent with their labeling. You should not do that. I spray with a cocktail of Mavrik, Enstar II, & Pentac. All in a single tank mixture. I do a repeat spraying 10 days later. Without fail, the entire collection is bug free and stays that way until the new recruits start coming in next spring-summer. Key is every living plant in the growing area or that potentially will be near the growing area gets sprayed. Don't want any hidden pests undoing the work of the spray. This cocktail seems to get them all, mealy bugs, scale, thrips, you name it. That's it. Most of these chemicals are not recommended for home use. There are others that will work, this is what works for me. I have too large a collection to play around with more home, or pet friendly products. 

For what it is worth.


----------



## The Orchid Boy (Oct 4, 2012)

This doesn't have much to do with the thread but what are some more 'acidiphiles'? I know Paph. delenatii is one.


----------



## NYEric (Oct 4, 2012)

Leo Schordje said:


> I will admit to using pesticides in a manner not consistent with their labeling. You should not do that. I spray with a cocktail of Mavrik, Enstar II, & Pentac. All in a single tank mixture.



_"Better living through Chemistry"_ - Sign at Dupont Bohpal!!


----------



## Rick (Oct 4, 2012)

Leo Schordje said:


> As I tell people in my talks. You can pretty much grow orchids in just about any mix you want IF you understand how and when to water. I grow in bark based mix, I know a local grower who grows the calcareous loving Paphs, like bellatulum and concolor in nothing but pure New Zealand Sphagnum, and she has keep plants growing and blooming this way for 20 years or more. It is just a matter of knowing how and when to water and fertilize.



Yes. This is the point I infer with the thread on EC management of pots/potting mixes.

Definitions of "calcareous loving", and "acidophiles". Are pretty much worthless to me since looking at the potassium overdose issue. Even the traditional "acidophile" delenatii grows best at pH 5.5 to 6.5 like every other paph, and as noted by Leo, a species that grows on limestone can be grown in sphagnum moss quite succesfully (theoretically an acidic pH).

But a commonality for all is that retention of monovalent salts (potassium and sodium) in the mix is minimized through appropriate watering/feeding rates. And the balance of divalent salts (Ca/Mg) remains above the monovalents.

If all you water with (and make up non Cal-Mag type ferts) is RO water, you will saturate your potting mixes with K pretty quick. Adding limestone or oyster shell extends the rate since what soluble Ca can maintain a positive ratio to incoming K into the mix.

If you water with tap water (the harder the more Ca available) you can get away with a higher K input with well drainging/non retentive mixes with good size well growing plants.

Conductivity measurements can be a good surrogate/crutch to "learn" how to water and feed, since you will be able to litterally be able to measure the build up of salts in any given type of potting mix.


----------



## Leo Schordje (Oct 4, 2012)

Thanks Rick, well said.


----------



## Stone (Oct 6, 2012)

Leo Schordje said:


> > New material I am looking at as an 'extender' that will retain structure, allowing a bark mix to last longer, is shredded rubber mulch. It was on sale at 1/2 the price of bark. I am now testing it to see how it works as a component in a mix. But I am testing on plants that are expendable.
> 
> 
> Leo, I've read that Shredded rubber should never be used as it contains toxic amounts of Zinc.


----------

