N. ampullaria compact growth

[mobile]

I too am not convinced the compact growth is due to lack of nutrients or the pot size. I have potted in quite a large net pot and the roots have nowhere near filled the pot. The primary media is orchid bark, with some added Sphagnum moss which grows mainly on the surface. The bark will be adding nutrients as it breaks down. I believe that the compact growth is due to the light.

[manders]

I'll contiinue to disagree on that one as amps can and do grow in full sun, 100,000+ lux in the tropics and are not small, and as allready mentioned, mine get at least as much light as yours and are not small either.

If an amp, or any nep, is not growing a climbing stem and trying to flower then somethings not right.

[Martin Hingst]

manders, I guess I wrote it elsewhere already: a high light level can suppress the formation of a climbing vine in many Nephentes species. Something I followed over many years - there is quite some information, if you read posts and pictures esp. of habitat plants under this point of view.

What makes sense: a Nepenthes in an open clearing will find no support for a climbing vine.

And as soon as climbing vines will reach the bright lit treetops, they will stop climbing as well.

 

And light level is a relative quantity, with at least two parameters involved: luminosity divided by temperature. So 100.000 lux at say 35°C may be far less than 50.000lx at 25°C - the latter being my actual conditions.

 

A recent pic that came straight to my mind is this N. maxima, part of the GFP cp calendar 2015 (btw worth purchasing again - and we made it even cheaper this year ;-)

 

Edited October 21, 2014 by Martin Hingst

[manders]

Martin,

Can you explain a little more about your lux vs temp theory?

[Martin Hingst]

manders, I am strongly hesitating to take any credits of being "my theory" ;-)

 

Something I observed when growing lowland tropicals, esp. Utricularia, was quite a strange paradoxon: I increased light level in my tanks to avoid etiolated growth, i.e. get shorter flower scapes. From a certain amount of light on, the plants showed even longer internodial distances, the higher the amount of light got. I stopped that at a point of 100.000 lux and started rethinking. The only explanation was the amount of heat increasing at the same time, while the plants had already reached their photosynthetical maximum.

 

Then an observation maybe everyone has made: plants growing outside colour up more nicely and show more compact growth in autumn than in summer, although light intensity is going down. Can be explained by the same reason: temperature is going down as well, so even a few hours of autumn sunlight have a stronger effect on the plants than a whole day of summer sun.

[manders]

Still not convinced. Its not difficult to think of species which vine perfectly happily in full sun, in fact i had one growing in my garden once, definately not at high temperature, in full sun, vined and flowered. Indeed about 15 years ago i had no shading at all on a particular greenhouse and no stunted plants. Also high light tends to give smaller leaves and large pitchers, what i see on these amps is small leaves and small pitchers.

Stunted maximas in a field can be explained by them adapting to the treeless conditions, no need to vine if theres nothing to vine up, they need to flower and set seed as fast as possible beore getting eaten by some browsing herbivore. Plants rapidly adapt to small changes in conditions, daises in a lawn tend to grow flatter than daisies in a border, because those that grow flatter dont get the flowers chopped off.

Veitcheiis still vine in full sun and grow allong the ground until they find a suitable tree to climb up.

All plants only have one goal and thats to reproduce as much as possible, if your plants produced a full size flower spike on a short growing plant that might be some evidence that the light is stopping the vining habit but the plant is healthy. If they produce a stunted spike on a stunted plant, i'd say that shows something else. No spikes at all would be bad.

If the vining habit has really been subdued then they should really be spiking now. How old are they?

I thnk its an interesting theory but too many examples where it just doesnt hold true to be really convincing, just an opinion...

[Martin Hingst]

Its OK manders. I am happy with mine.

[Dave Evans]

Then an observation maybe everyone has made: plants growing outside colour up more nicely and show more compact growth in autumn than in summer, although light intensity is going down. Can be explained by the same reason: temperature is going down as well, so even a few hours of autumn sunlight have a stronger effect on the plants than a whole day of summer sun.

Hello Martin, I don't think that is what is going on at all.  First by the time the autumn has arrived, the plants have finally adjusted to summer conditions.  Two, warm temps and high light level degrade the colorful Betalains of Nepenthes.  The cooler, less bright conditions keep them vibrant in the same way keeping red wine in the dark and in cool temps makes it last.

 

The shape of the Nepenthes plant is controlled by the flow of auxin.  Manders, please don't start in again how gravity is not constantly affecting the flow of auxin in the plant and effectively molds it in place in the habitat.  That is exactly what is going on with Nepenthes plants.  The tendrils and leaves of plants without any supporting vegetation or structures to climb on will not have their leaves the same positions as climbing plants, which directly affects the shape of the plant via auxin flow.  Each species have their own particular reactions though and can use the same auxin mechanisms to produce different effects.  Like how N. ampullaria sets basal rosettes in a fashion only a couple of other species do.

 

When the climbing stem reach the top of the canopy, the internodes do get smaller and the plants make more of a rosette shaped growth when they flower.  This might help keep the inflorescence more stable.  They take quite a while to set seed... 

Edited October 23, 2014 by Dave Evans

[manders]

Manders, please don't start in again how gravity is not constantly affecting the flow of auxin in the plant and effectively molds it in place in the habitat.

Auxin does not work in isolation, there are other hormones that affect plant growth...

[Dave Evans]

Right, of course, it doesn't work alone.  It is "just" the main system for maintaining the plants' optimal shape as it develops and grows. :)

 

And, of course, auxin has different "modes of operation" as well.  Auxin is really important in general for plants.  If we didn't have hemoglobin, our blood would have to use a different, less effective oxygen carrier, but if plants could not use auxin, they might not even be able to exist as we know them!  And yeah, I get hemoglobin is a specific chemical whereas auxins are a "class of chemicals", however I don't believe that makes my previous sentence less accurate.

[Martin Hingst]

hups - wrong thread sorry ;)

Edited February 16, 2015 by Martin Hingst

[NepXGorgicus]

Hey mobile, that's a pretty cool little Nepenthes ampullarium you've got there (pun intended).

 

It looks as though not much air is getting into the terrarium because of the kind of lid you have on it. I may be wrong, but restricted air flow will hinder the plant's growth.