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Theoretically speaking, would a high phosphorus fertilizer increase the size of the caudex seeing as phosphorus promotes root growth?
What do you think?

A. obesum is quite vigorous and can take a lot of water if warm and growing, so I'd assume generous feeding of any (reasonable) type would promote caudex growth.

esp_imaging wrote: ↑Fri Jun 15, 2018 12:38 pm A. obesum is quite vigorous and can take a lot of water if warm and growing, so I'd assume generous feeding of any (reasonable) type would promote caudex growth.

Yes you are absoluetly right. I have 3 adeniums, two of them are the same size so i'm gonna experiment with fertilizers on one of them. Maybe one in three waterings will be with high phosphorus fertilizer

I wonder if shallow x deep pots would give different results. What do you guys think?
Elie, as far as I know, caudexes are part of the stem, not roots, so I don't know whether your reasonable makes sense. Anyway, it is something to be tested.

mmcavall wrote: ↑Fri Jun 15, 2018 4:09 pm I wonder if shallow x deep pots would give different results. What do you guys think?
Elie, as far as I know, caudexes are part of the stem, not roots, so I don't know whether your reasonable makes sense. Anyway, it is something to be tested.

I believe the lower part of the caudex is the enlarged roots for water storage; sort of like a taproot. I think the very definition of caudex is root and stem.
I don't believe shallow pots help the caudex grow bigger. You simply raise the underground part above soil level which makss the caudex look bigger. Then the below the soil roots continue to get bigger but spread around rather than go deep. I grow mine in deepish bowls and the stem is quite fat. However, if i manage to get seeds, acclimate the seedlings to full sun and cut the growing point, i think i can manage to get shorter wider caudex and a more compact plant

I do agree. All makes sense.
Just a final speculation: is it possible that growing in shallow pots the plants would react as if they were growing in an extreme environment , thus investing in water storege structures, i. e. the caudex?

mmcavall wrote: ↑Fri Jun 15, 2018 7:14 pm I do agree. All makes sense.
Just a final speculation: is it possible that growing in shallow pots the plants would react as if they were growing in an extreme environment , thus investing in water storege structures, i. e. the caudex?

In shallow pots, the water evaporate very fast - specially in our hot environments. So you could be on to something. Maybe the plant would react to the rapid loss of water from around it to store as much as it can of it?

Well, yes, I don't know....it is just speculation. But I see lots of Adeniums grown in deep pots, and they don't have massive caudexes such as those we see in the pictures of habitat (or of Thailand growers). Maybe is just lack of sun...
Anyway I have about 12 young plants from seed, and some of them I will grow in shallow pots. We'll keep exchanging experiences here...

Yeah it's good to have a thread about adeniums. I'm gonna change the title to adenium advice thread.
Meanwhile, i really like the ones i have, they are some of my earliest succulents. so i think im gonna buy more to experiment with to test different cultivation parameters and report back here.
Are you cutting the tops and taproots yet Marcelo?

I've cut the tips of some of the plants. As for the roots, I wasn't aware until reading your question (I've just seen some videos on YouTube).
I have few and very young Adeniums, all grown from seed:
Adenium arabicum 'Shaba' (Mesa Garden)
A. arabicum (Vipassana)
A. obesum (Vipassana)
Plants of the first batch were transplanted to clay pots (most are shallow pots) or to deeper plastic pots (two plants).
Plants of the second and third batches are still in the pot were they were sowed.
As it is winter here, I will let them alone until September.

Arabicum makes a much more beautiful compact plant than obesum. Unfortunately, i can't get seeds due to paypal restrictions. These are not my first choice but I only have 3 obesums: a double white adenium and 2 normal colored ones. The white one doesn't produce pollen and it only produced seeds once but i stupidly gave them away to a nursery. I'm gonna pollinate them this year if i'm around when they are flowering and try to work with seedlings from early on.
If anyone passes by here and has excess seeds of obesum, arabicum (and somalense) and multiflorum i will happily trade for cacti seeds
Btw these obesums were the last species to flower this year and last year they were the first. Last year was much colder (by 5 degrees celsius). I would have though warmer temperatures will encourage earlier flowering

Removed some topsoil and this one looks like it has some interesting stuff going on underground. This will be the top candidate for a shallow pot once the root mealies are taken care of.

Phosphorus promotes flowers, while potassium is better for root development, from what I’m familiar with, regarding the functions of NPK. The trouble with human thinking is that while it makes sense to assume increasing ancertain element that is known to have an impact on one aspect of growth should work, but the reality is virtually all plants utilize the same ratio of NPK and excess just accumulates as salts or at best is flushed away, unutilized, like humans taking high doses of vitamins. A balanced fertilizer, genetics, and proper culture yield the best caudexes; with time being a valuable tool as well.