Paph growing upwards?

I have two Paphs in my collections of which various new growth are growing upwards on very slenders growths. They try to make new roots along the way but these tend to turn brown / black very fast as I'm growing indoors and humidity is quite low.

Paph. lawrencianum:



Paph. sukhakulii:



Is this a normal trait for these species? They both belong to the Sigmatopetalum subgenus. Or can it have something to do with my culture? Is there any specific I should do with these growths?

We've discussed this growth habit before (we usually called them "Barbata" subgenus). You might try the search function to pull up some of these old threads.

This is a frequently observed growth habit in this subgenus. To see it in these two species is a bit novel, but it is very common in barbatum and calosum. I've also had it happen in purpuratum, sangii, and appletonianum.

One speculation is that many of this subgenus are true forest floor species that grow in moss and leaf litter accumulations. In order to stay above the leaf litter accumulations this growth habit is necessary. But obviously in our pots, leaf litter isn't building up. So the response does not appear due to mechanics of soil depth.

With my recent rampage on the ills of excess potassium, I think nutrition may once again be a culprit. I have both a barbatum and calosum var sublaeve that had a major case of the runners. Since I reduced the K relative to Ca and Mg, the plants have been producing basal growths without elongating the stems. Leaf color is much darker now, and pattern contrast is stronger too.

I got that problem sometimes, however if Rick grows his plants in baskets, I suspect the problem should disappear...

To my understanding, as I saw several species in the wild, it is related to the leaf litter condition originally. salts concentration, pH, and I feel, water content, CO2, O2, NH3 contents. Not watering enough apparently triggers the problem too, maybe as a salt concentration increase.

So far watering daily things like sangii and lawrenceanum stopped the problem completely for me. But I did get it sometimes for things like Maudiae The Queen, barbatum, etc... As a note, barbatum grown in sphagnum and watered daily in Malaysia did not exhibit the problem, but the ones that dried out in sphagnum did exhibit very long stolons like stems...

Roth said:

I got that problem sometimes, however if Rick grows his plants in baskets, I suspect the problem should disappear...

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I've moved about 80% of my adult plants into baskets, but not all (yet!).

But the calosum var. sublaeve I refer too is still in a pot. So this plant only got a nutrition change without change in potting substrate.

I have one paper on leaf litter nutrients from a West Sumatran rainforest. There is a cyclic nature of the relative abundance of nutrients over the course of the year. In this paper there was a short burst of relatively high K in Jan, Feb and May, but Ca prevails (over 2X) for the year with a broad peak in summer. There is a peak of nitrogen and phosphorus in the winter months. Actually silicon is much more abundant than K in leaf litter too.

Anyway the fluctuations in nutrient availability along with changes in rainfall may be cues to whether the plants should be elongating stems or growing roots.

Put a pot and media around the main growths and let the plant grow.

It happens often with lawrencianum. Haven't seen it yet with sukhakulii, but since its so common with other barbata's, its no surprise.

one of my two sukhs is climbing like that but my other isn't. don't think they're from the same cross and since i lost the tag, i probably never will....

anyone know if it's plant specific or if all the plants in a cross will?

NYEric said:

Put a pot and media around the main growths and let the plant grow.

Click to expand...

In fact if the media is not 'suitable' or the feeding/watering is not 'suitable', whatever it means to the plant, it will climb even more, sometimes indefinitely for months, before eventually making a leaf or two. I have seen it on all the mottled leaf paphs, and even kolpakingii and gigantifolium can eventually do it quite severely...

Apparently the plant declares that the potting mix is not suitable, and try to move somewhere else, as long as the place is not suitable, it will still make this kind of funny stolon.

Looks like I need to repot then

The lawrencianum is potted in a mix of bark, perlite, charcoal and spagnum. The pot itself isn't too big for the plant but I haven't noticed any new root growth so it stay wet for too long. I'm thinking about repotting it in a smaller pot and loose the spagnum and adding a calcium source.

The sukhakulii is potted in mostly bark but there is quite some spagnum in the bottom of the pot that prevents water from leaving the pot quickly. In the end it drains completely but isn't instant. Thinking about keeping it in a similar sized pot with a mix of bark, spagnum and perlite. Will do some searching before I make my final choice though.

Repotting the sukh will be a challenge though as there is quite some difference in heigth of the various growths of this plant.

Any input is apreciated though.

Weird, however thanks for sharing of your case so that I have a better understanding of my albino suhkakulii and lawreanceanum. Hopefully they wont have the same problem.

I've been having great success moving barbata types into the wooden slat baskets.

I line them with sphagnum moss, add in a handful of coarse limestone chips or hydroton balls (intermixed with the roots) pack in loosely with more sphagnum, top dress with sand, water in the sand and pack in a bit more moss.

Sometimes I may add in a pinch or two of aragonite "Cichlid Sand" for pH buffer. I usually add a pinch of some type of local live moss that usually overgrows the baskets.

If you tend to water heavy (like I do) then you get great aeration for overpotted plants. I used to have to pot really tight with very coarse substrates to get this level of aeration at the roots.

Check out some of Bjorns recent threads on his basket method.

Rick, with your paphs are you seeing any roots come out of the basket?

Justin said:

Rick, with your paphs are you seeing any roots come out of the basket?

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Yes
Rothschildianum and sanderianum probably the most aggressive in this way. But henryanum has too.

Recently tigrinum and barbatum. Most of the time they turn and go back in. They are not like Phal roots that are gripping the outside of the baskets.

Since I started this topic I have repotted both plants.

The sukh wasn't that bad to repot. The rizome between all the growths was intact and the hight difference wasn't that big. So I repotted it in a different medium and I'll see how things go the coming years.

The lawrencianum was a different story, after pulling the plant out of the pot it fell apart in parts. an older previous bloomed growth was affected by some rot as well so I removed it completely. What I did after that was remove all the leaves from the "stolon" that grew up so the new root "nodes" were uncovered. I ended up spliiting the parts in two, two bigger growths were placed close to each other in bigger pot and the other two in a smaller pot. So the growths were placed in a different medium without spagnum and added calcium. We'll see how things work out.