I have trouble growing orchids in bark...

[The Orchid Boy]

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]

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

 

[eggshells]

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]

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]

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]

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]

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]

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

 

[keithrs]

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]

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]

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?

This is the single most difficult thing to learn and many pages have been written about the subject. There are so many variables that the ONLY way to know is experience (which sometimes includes losing plants) Some people are ''waterers'' (like to water...me) and others are less inclined. If you like to water, then you should aim at a mix that dries out quickly. If you're not into watering that much, you need to include finer and/or more organic material in your mix.
Personally I probably water too much so for me a good way of making up a mix is to gather all of my favorite ingredients (and most will be hydrophillic) and when I'm happy with that I add the hydrophobic stuff according to how much watering the particular plant is going to get. In my case I love granulated polystyrene (and so do the orchid roots). I find I can water every second day with this no problem almost everyday in summer. I think its too hard to control moisture levels for an extended period with sphag, and the slightest bit of feeding or lime will turn it into mush. Use it as a top dressing instead. Or even better find some live sheet moss and wash it well, chop it up and mix it with 10% chopped sphag. It works great and lasts much longer than 100% sphagnum.
A great way of knowing when to water is to learn the weight of your wet pots and your dry pots. You'd be surprised how accurate it can be! You lift your pot and you will usually know what to do. If not leave it for one more day.

 

[The Orchid Boy]

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]

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]

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]

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]

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.

 

[Ross]

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]

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]

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]

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.