Phrag Potting Mix?

[Nepenthesis]

I researched common mixes for phrags and bought some ingredients, but I want to make the best mix for my growing methods/conditions. Here are the materials I have...

1. Small orchid bark
2. Charcoal
3. Vermiculite
4. Long fiber Sphagnum

I'll be growing my phrags in a greenhouse that is in the 50s at night and 70s to 80s in the day depending on season and weather. It is about 60% humidity in the day and 80-90% at night.

- I'm planning to sit their 6" circular pots in water trays
- There's a lot of airflow in my greenhouse
- The greenhouse is in the sun half of the day, which is more hours in summer than winter (but in summer I have 50% shade cloth over the greenhouse)

Any suggestions for the part to part ratio for the mediums listed above?

Thanks!

[quiltergal]

If you plan to grow them in saucers of water I would leave out the sphag. The sphag will get stale faster than the rest of the media, and it's not really necessary. The rest I would mix in a 4*1*1 ratio.

[MrHappyRotter]

If you ask 8 different people that question, I suspect you'll hear 8 different opinions. Speaking of opinions, here's mine ...

I say skip the vermiculite. Do 50/50 or 75/25 bark to charcoal. Then break up the sphag in to smallish chunks, and mix in a small amount.

The thing is, if you're growing your phrags wet, then it's true, the sphag will break down much more quickly than the bark and charcoal. But I think it's good stuff, used in moderation.

Initially, moss helps hold water and wick it towards the roots at the top of the pot. Fresh bark and charcoal have a hard time retaining water until they've had time to age and break down a little, so the sphagnum bridges that gap.

As the sphag deteriorates, it supplies a small amount of nutrients for the phrag and helps acidify the potting media a bit. As long as you use it sparingly, the tiny bits of broken down moss will eventually flush through the pot, assuming your mix is otherwise open and airy enough.

I use this strategy with my phrag mix, which is primarily composed of inorganic components. I add a small amount of sphag to the mix, which helps moderate the pH (since I also use oyster shell to provide extra calcium), and over time as the moss breaks down, I just add a small amount to the top of the mix, unless natural live moss has taken over and started growing at the surface.

[Nepenthesis]

Originally Posted by MrHappyRotter

If you ask 8 different people that question, I suspect you'll hear 8 different opinions. Speaking of opinions, here's mine ...

I say skip the vermiculite. Do 50/50 or 75/25 bark to charcoal. Then break up the sphag in to smallish chunks, and mix in a small amount.

The thing is, if you're growing your phrags wet, then it's true, the sphag will break down much more quickly than the bark and charcoal. But I think it's good stuff, used in moderation.

Initially, moss helps hold water and wick it towards the roots at the top of the pot. Fresh bark and charcoal have a hard time retaining water until they've had time to age and break down a little, so the sphagnum bridges that gap.

As the sphag deteriorates, it supplies a small amount of nutrients for the phrag and helps acidify the potting media a bit. As long as you use it sparingly, the tiny bits of broken down moss will eventually flush through the pot, assuming your mix is otherwise open and airy enough.

I use this strategy with my phrag mix, which is primarily composed of inorganic components. I add a small amount of sphag to the mix, which helps moderate the pH (since I also use oyster shell to provide extra calcium), and over time as the moss breaks down, I just add a small amount to the top of the mix, unless natural live moss has taken over and started growing at the surface.

May I ask why you would leave out the vermiculite?

I grow only Nepenthes as of now, as well as massive amounts of live Sphagnum moss. I pot most of my Nepenthes in pure Sphagnum so that I don't have to water them as often. Would it be bad to go 30 or 40% Sphagnum, 40% orchid bark and the rest charcoal?

Since Phrags like to be considerably wet, can I add live Sphagnum to the top of the pot to help lock moisture in?

[Laserbeak]

I've had some really good results with Aussie Gold paph/phrag blend.

[jeremyinsf]

The only time I use sphag with my phrags is when that's what I'm growing them in exclusively. It's also a great transition media but I don't regularly add it to other mixes.

The best phrags I get have lava rock in the mix. And quite a bit of it.

I only use Orchiata bark. For *bark*, I consider it to be the best in the world and can't imagine using anything else.

My charcoal is about 10%.

[billc]

MrHappyRotter is right, 8 people will give you 8 (maybe more) different opinions. You really just need to start with something and see what works best for you in your conditions. Don't make big changes, just little tweaks so you have some control over whats works and what doesn't.
I would stay away from the vermiculite in an orchid mix also. Vermiculite tends to retain moisture and you will get fertilizer/salt build up rather quickly. It's like a little sponge and flushing with clear water won't release the salts that have saturated the vermiculite. Those build ups are death to paphs and phrags.
I think when people say grow them wet it's more about a continual source of fresh water, not sitting around in the same water for several days.

Bill

My mix consists of mostly perlite with small amount of bark, charcoal and river stones added.
I just repotted my besseae to accommodate new fan. It looks like this:

[Vanda lover]

I have mine in s/h in lava rock and it loves it. I recently bought another that is potted in bark and sponge rock. It has recently been potted and is in spike, so I won't change it to lava rock yet, but I will when I need to repot. Lava rock doesn't break down and it wicks very well.

[NYCorchidman]

This might sound crazy to some, but I have been growing mine ( Eumelia arias) in fine podwer like form of coconut husk with a saucer filled with water for past few months.

It is very happy.