Bark vs sphagnum

[avian]

I have a few Phalaenopsis that need to be repotted. They are currently in sphagnum. Should I repot them in sphagnum or would bark be OK? In the past I've repotted a few Phals into a bark and pumice mixture but since the ones I want to repot are doing OK in sphagnum I'm thinking maybe I should stick with that. Any recommendations are appreciated. TIA

[estación seca]

Phals can grow well in bark or sphagnum. Watering is different for the two media. If you're happy with your results there is no reason to change media.

[Ray]

I agree with the last comments. Besides, if you repot into an entirely different potting material or mix, you will likely lose a lot of the existing root system.

[MateoinLosAngeles]

I find both to work well but it depends on your climate and the timing of the repot. Changing media has always set my Phalaenopsis back dramatically even when growing new roots. If I repot them before growing new roots and I'm changing the medium this is dead roots and dead Phalaenopsis secured. The only instance where I've had success repotting at any time of the year is when transitioning Phalaenopsis to Semihydroponics. They seem to adapt very well and don't experience setback. I've repotted sick Phals in S/H and that has helped stabilize them and give them time to grow new roots. Now, my entire Phal collection is in Semihydro except for three plants... guess which plants are doing better...

Now, if your Phals are growing new roots, you can do pretty much whatever you want. But I would imagine that's unlikely at this time of the year. Pick the medium that best adapts to what you can provide to the orchid. If you can and want to water it every day, then go for bark. If you want to water once a week then go for Sphagnum.

A few considerations:

You want the medium to be consistent, that is, each piece to be of similar size. If you want to mix bark with perlite, charcoal, leca, and some sphagnum you want to mix this well and make the mix consistent. Layering has resulted in soppy messes for me.

If you go 100% sphagnum: pack it TIGHT and water from BELOW. I have killed so many orchids by layering sphagnum loosely, I don't know why I see that recommendation everywhere. I live in a dry climate and it has NEVER worked for me. Loose sphagnum leads to a soup in your pot and dead suffocated roots. Water lightly and let the moss absord the water. The beauty of Sphagnum is that it distributes the water evenly so you need to learn to water appropriately.

If you go 100% bark consider Orchiata and make sure to really drench the medium every time you water. I keep my cattleya-alliance and brassavolas in baskets in a mix of orchiata bark, sphagnum, leca, charcoal and perlite. I currently use Precision for seedlings and Power for adult plants. I find that after seedlings have grown they can graduate to Power size and skip "Classic." I think more humid climates would favor "Power +" and "Super" sizes. I water by soaking them for 15 minutes in an external container (usually a pale or deli cup) twice a week and this has been successful for me. Phals would probably want this watering frequency to be three to four times a week (every other day) as they don't like to get fully dry.

Pack tight regardless: I think the "packing" loose tip is misleading. I've found that the aeration comes from choosing the right medium and the right particle size but packing loose leads to big air pockets and insufficient stability. If you pick chunky bark and pack it with chunky media of similar size, no matter how much you pack it, there'll be enough space between particles to provide aeration. Besides, packing will help stabilizing the plant. Use a stake if it still wobbles. We don't like it to wobble. I use slitted pots or drill my own holes, some find this unnecessary for the sides of the pot but drainage holes at the bottom should be a must regardless.

I urge you to consider potting one of your phals in S/H and use that as a control to compare with your other Phals. If potting in S/H I've stopped cutting orchid roots at the time of repotting, old roots slowly degrade and get washed out through regular watering and the leca can't degrade. So I find the cutting to be unnecessary. I had plants without any "healthy" roots repotted and they didn't dehydrate in the time that it took them to grow new roots... so I would imagine even "bad" roots can still provide some absorption to the plant for the time it takes it to grow new strong roots... whereas this wasn't the case when I repotted truly rootless orchids.

I also personally follow Ray's methods as explained on FirstRays.com and I use Kelpak. I've read his website back and forth and I've literally tried everything else and everything has lead to dead orchids for me... except for Ray's care tips, which have always come to the rescue. All my plants that have been under the "First Rays Regime" have grown without a hiccup.

Finally, one of the First Rays tips is soaking the entire plant in a Kelpak solution before repotting. I've done this for 99% of my plants, sometimes overnight... Has that been the trick that helped my Phals? I don't know. Have they grown roots and come back stronger from set backs? Yes they have. So I keep using it, alongside Quantum.

[tmoney]

howdy!

i felt like chiming in only cause here are a lot of things! first, mateo i agree with several things you mentioned. certainly i attribute a lot of our orchid successes to kelpak. it is a great product. also, rays and others guidance on s/h has been a tremendous eye opener for growing in inorganic media and simplifying the whole process. finally, i 2nd the rec to try phals in s/h. it is a very rewarding learning experience and a way to push the growing envelope and test things. after a couple years of growing we r just now starting to experiment with pure moss growing.

second inning *preface*- our experience is limited. but, conditions dependent of course, we haven’t needed to water our phals in bark more than once a week. with the soaking method that is plenty. of course, others mmv, but even our overflow phals at our workplace get watered less often than that and they are ALL in nice spike right now with super healthy leaves and roots. we treat our species the same, and with once a week many of them are also putting out spikes now at home. so, im not sure i would tots agree that phals in bark need more than once a week.
of course, again tho, if you live at the equator or in death valley or ou r growing outside in south texas or whatever, you would need to water more. but im just saying that for the typical indoor windowsill grower at mid latitudes, one soaking a week seems plenty

aw crap...3rd inning *preface* our mix isn’t just bark i suppose, it’s a mix of bark, leca, and a bit of sphag, but still thing i was trying to say is that they mostly dry out pretty good between watering, specially in winter

[MateoinLosAngeles]

Originally Posted by tmoney

of course, again tho, if you live at the equator or in death valley or ou r growing outside in south texas or whatever, you would need to water more. but im just saying that for the typical indoor windowsill grower at mid latitudes, one soaking a week seems plenty

We're in agreement! I shouldn't even talk about water frequency as it is so dependent on the environment that one can provide to orchids, but I was trying to illustrate that watering frequency can dramatically change and can't be assumed on the medium alone. The examples given come from my personal experience where bark pots can really get bone dry in 72 hours or less. If you live in the desert some people mention watering twice a day... But my mom in Northern Spain might not need to water her orchids for two weeks and she probably can simply run water through the pot without soaking it. Even in bark. If I don't soak it for a good 15-20 minutes, it's dry pot in a day. Sometimes that same night.

As an example, my mom's region has a very steady RH of 80% throughout the year, a chart would look like a flat line. If you live in Berlin you might experience 80% RH between November and February, for it to drop to 60% in Spring and Summer. The opposite happens in Los Angeles with humid Summers where RH fluctuates between 60%-70% and dry Winters between 40%-50%

And this doesn't include the effects of temperature, length of day... So yeah OP needs to adjust watering to their circumstances

I do think that as a general rule of thumb, however, we can accept that mostly Sphagnum media will tend to retain water potentially for longer than mostly bark media. But this even can change since tightly packed Sphagnum can potentially retain less water. I've found S/H to be the only potting strategy to be "overwatering proof."