Adonidia merrillii when does it trunk?

[mxcolin]

I've had my Christmas Tree Palm for just over 1 year. It looks healthy and is throwing out new growth but I'm wondering when I can expect it to go from where it is today to starting to see some trunking? At this point the oldest fronds just fall off.

 

[Palmlover_78]

Hello, Beautiful Palms you got there ,  They need a bit more light, the Fronds look a little stretched, especially with a triple.  I think they won't trunk for at least an other year.

[ExoticPalms]

I've started growing 4 in water bottles entirely indoors for about 5 or 6 years now since they were little blades of "grass". They have since tripled in size, but not until the roots started packing enough on the bottom were any of them transplanted into slightly larger see through plastic containers. I didn't re-pot them until about 3 feet tall. They will grow very slowly indoors with containers that are too wide and big. I've tested this with many different Christmas palm seedlings. The focus should be the roots early on.

They seem to like taller thin planters at a young age to acclimate in, and then build up a solid root structure before they can take advantage of a bigger container like you have. They might be ugly, but they are worth the ugliness for a while. I think it's important to keep these sort of root bound for indoor growing,  but still letting the tap roots room to push further down. The depth of that planter is nice, but it doesn't need to be that wide for such a small tree cluster. I wouldn't recommend changing it though since it's handling it okay. A wider bigger pot will probably facilitate growing out more nutrient rich darker wider leaves vs height and faster growth to the trunk. Try an additional overhead light source too, indoors for height. You'll more than likely be looking at not much outside of the green crown part of the "trunk" for many years to come as an indoor plant. If I were you, I'd let it live outside where it's getting full sun at least for a good part of the year or more.

[mxcolin]

Thanks for the detailed response. I’d love to put it outside for a bit but our summers are brutally hot and dry and fear that it might get crushed. Anything tropical I’ve put outside gets fried. Winters probably a little cold for it too. 

[JLM]

15 minutes ago, mxcolin said:

Thanks for the detailed response. I’d love to put it outside for a bit but our summers are brutally hot and dry and fear that it might get crushed. Anything tropical I’ve put outside gets fried. Winters probably a little cold for it too. 

Do you acclimate them to the sun? If not, that would be why it gets fried. In order to put it in full sun from being indoors, you need to slowly "push" it out into the sun over the span of probably a month or more. Make sure as you acclimate that it gets lots of water.

As for winters, 9b is a stretch for these, as they are pretty solid in zone 10b but will work for a while in 10a. If you wanted to move it outside, personally i would just wait until next spring whenever it gets warm and stays warm. Would start the acclimation process then since the sun wont be quite as harsh. If you get any days where temperatures are well above 100F, i would put it under shade for the day(s). 

[greysrigging]

I have them growing in full sun in Darwin, Northern Territory, my mature specimens are prolific seeders, with ( it seems ) 100% strike rate, almost to the point of being 'weedy'.
i have some in pots in reasonably deep shade, some in partial shade.....too shaded they appear spindly and not as robust as the ones in bright light and sunshine.

[mxcolin]

Our weather is far from tropical though like Darwin. 40°C days and little to no humidity. 

[DCA_Palm_Fan]

Here are a couple photos of mine. Purchased in early 2018.  Mine was the same size as yours at time of purchase.   It’s getting rather large now.   Keep in mind I am in a zone 10A humid tropical climate which is what these want / need.   
 

outside of this kind of climate I’d think the only way you see them get large / live up to their potential is in a greenhouse.