Have you lifted it up from the pot to check on its roots? If they are pretty root bound and seem somewhat crowded, then it would be fine to repot into a pot that's one size larger. I have a Pachira that's around six feet tall and it grew just fine in a pot that seemed small for its size. But I finally had to break down and repot it last year into a larger pot, mainly because it was so top-heavy that it kept falling over when I had it outside. It didn't seem to mind having its roots disturbed. I just carefully knocked off all of the old soil, and repotted with some fresh.

If you do decide to repot, make sure to use a soil that doesn't stay too wet and is fast-draining. I used the Miracle Gro brand for Cactus & Succulents, and it worked just fine for my money tree. And when you water it afterwards, make sure you water it thoroughly and let the excess drain completely away. Their roots need access to fresh air just as much as they need access to water. Which is why a fast-draining mix is the best option. If their roots can't breathe, that's when they'll rot and you'll run into problems.

I don't think that being in a North-facing window will be sufficient. Pachiras love lots of light, so a Southern-facing window would be much better for it, if you have one available. In fact, when I grow mine outdoors, I keep it growing in direct, full sun the entire time. I only mention that just to show you how much light they can tolerate. But growing yours indoors, give it access to as much light as possible, and it should do just fine.

I have not checked its roots yet. I'm pretty busy during the week, but I'm planning on working on my plants this weekend.

I think I will repot, even if the size seems ok, just because I'd rather have it in a grittier, fast-draining mix. Thanks for the suggestion of soil!

I do have southern-facing windows, and eventually I plan on putting my plants (at least some of them) outside during the summer!

Thanks for the help!

Additional question:

What should I do about fertilizers? I've heard that it's more important to fertilize plants that are in gritty mixes than plants in regular potting soil, is this true? If so, what sort of fertilizer should I use, should I dilute it, and how often should I use it?

Thanks again

They don't seem to mind being repotted and having their roots disturbed. That's what I did for mine, after I bought it. The roots were only at the very ends of their trunks, so I just raised the plant up itself, giving the roots more room to grow downwards.
I cant speak on behalf of any potting mix that is grittier than the MG Cactus & Succulent soil. But for me, the MG C&S soil worked just fine. When I repotted it again last year into a larger pot, the roots had filled in the rest of the older pot quite nicely.
I only fertilize my Pachira during the warmer months, and only about once a month at the most. I say at the most, because I know that there are many times when I've forgotten to, and it doesn't seem to phase my money tree one bit. If/When you do decide to move it outdoors, place it in a partly shaded location at first, or the leaves could burn. After about a couple of weeks, you can move it into full sunlight, if you want to. But if not, partial shade is fine, too. I've already moved mine outdoors, even tho the nighttime temperature is still unusually chilly. Mine stays in full sunlight, even during the hottest months of the year. I just make sure to keep it well watered during that time.
Well, good luck with your Pachira. These are definitely one of my favorite plants. Other members on here grow Pachiras, too, and hopefully they'll give you some great pointers of their own. Please feel free, and don't hesitate to ask any questions that you might have in the future. :)

Pachira greatly resent root-disturbance (i.e. re-potting) at the wrong time of year (Fall - Spring). If re-potted during late May - July, they will bounce back very quickly and with renewed vitality. Of course, re-potting any stressed plant is going to be tricky.

The best mix that I've found is very coarse, free-draining, and porous. In short, a mix that can be watered copiously year-round, without worry of root-rot (the number one killer of Pachira). My mix is screened bark, perlite, and some sort of porous grit such as scoria, pumice, or turface (sometimes a combination of scoria and turface).

During the prime growing season, I fertilize full-strength, once a week.

Josh

Thanks Josh!

Soon after my last reply, I did repot (even though I think it was a little bit early) with a much grittier mix, although not using a hand-made mix (I got a cactus/succulent mix and some bark and gravel and mixed them b/c I didn't have access to the components I would like to use).

I also moved my pachira to a southern facing window.

I've had a problem though, which is that within the past few days, two hands have turned yellow (both are coming from the same trunk, I believe). I assume that this is from the shock of not only moving pots and soil mixes, but also moving locations. All the other trunks have healthy green leaves though, and there has been some good new growth (the new hands are all shiny green leaves).

I can post a picture tomorrow if that would help, but is there any way to alleviate the stress?

Thanks!

It may have been from the repotting, but as long as it's growing new leaves, it should be doing fine. I doubt that it was from moving it to a Southern window. I've been having to move my Pachira back inside at night several times, because of the unusually cold nights, and it hasn't phased it one bit. As long as no more sets of leaves begin turning yellow, your money tree should be okay and will love its new, brighter location.

Indeed, a Pachira that gets more light will be happy....as long as it isn't moved into direct outdoor light, in which case the leaves will turn a paper white as they burn. But indoors that won't be happening.

The yellowing leaves are from too much moisture in the root-zone, or dead roots directly. Feel that particular trunk to make sure that it hasn't softened at all. If so, remove it immediately.

Josh