If it was underwatered, it would swell up in 24 hours or so. Mine felt wrinkly and soft. watered. A day later, and hard as a rock...

Due to having just purchased it, I'd say it's probably rotting from overwatering. That's the most likely cause. Yes, I read the post...but chances are..that's the cause. Maybe it started before you got it? Adeniums don't usually get underwatered ;)

In my case..... its grown in mineral.... I have a echinocactus ingens thats really hard to get watered properly. it drains well, but also heats up. Increases water losses...

Laura, was the soil moist or dry when you recently took the plant out to check roots? Based on the timeline described, it looks like you've only watered the plant 2 times in approximately 4 weeks? That seems like too little water for a baby Adenium in full leaf and potted in a grittyish mix, but in my experience the leaves dry up and fall off when the plant is under watered, which doesn't appear to be the case for your plant. Adeniums can be treated like tropicals when in full growth mode assuming it's hot enough and your mix drains well. (Not sure if windowsill conditions can provide that.)

You're right...from what you're showing us, it looks good. It may well need more moisture or even a temporary humidity tent (as odd as that sounds).

I agree time to water. Be gentle and bury it back as long as you don’t tear the big root you can give a drink tomorrow;). If you do break the big root off, wait a few days to water.

You have to remember your little guy is pretty much a seedling. At least I would consider it still a seedling;). So it’ll need more water than an adult plant. It looks fine just thirsty. Depending on how fast the water disappears i‘d say watering your it once a week during the growing season should be sufficient. If where you live is hot and dry during the warmer months you may want to up it to every four/five days, but if there is still moisture in the mix wait another day or two. You’ll get to know your plant soon enough;). Goodluck:).

While you have it out of the soil, I would consider repotting it into a different medium. This looks like a regular potting soil, which isn't always the best option for cacti and succulents. If you water too much, the plant will rot--but if you water too little, the soil will compact around the roots and form, quite literally, a brick that is next to impossible to rehydrate. My adeniums are in a gritty mix, a 1-1-1 ratio of quarter inch granite chips, turface, and pine bark fines. Since yours is a seedling, maybe just do a 1-1 ratio of perlite with whatever soil you are currently using for more water retention and less soil compaction.

Alyssa - that is interesting that you see the need for more grit. Potting mix looks pretty chunky (gritty) to me, but maybe it is more dense down below. I do my best assessments by sticking my hands into the soil. LOL

Crenda - I agree, the top looks chunky. In the same breath, chunks can cause the soil to dry out too quickly...it really depends, like you said, what is under the surface layer. If it’s mostly peat moss, the little guy might benefit from added perlite. If it’s chunky all the way through, swap for a smaller grit medium that allows for more water retention without getting soggy like more perlite or the turface/granite/pine bark as mentioned. Whew, so many options! Lol

Too many bark chucks in that soil for a healthy Adenium. If those larger chunks were sieved out, and some more grit in the remainder, I'd think the plant would be happier.

Crenda - wow, that IS a big bag! Lol I’ve only seen those at specialty greenhouses, props to you for persuading your local HD!

I would change the soil. perhaps a 50-50 mix of cactus soil and perlite. When the plant gets some girth on it, switch it to a gritty mix [see the container gardening forum]. As weather permits, get it out of the window and into a sunny outside spot if you can. M2CW

Yea that stuff out of the bag is not good even if it says succulent. Look it up there are several comparisons. that stuff holds water pretty good(real good actually). I go 80% pine bark 10% soil or mix of soil compost, and 10% coco coir. It drains like crazy.

https://www.youtube.com/watch?v=jsyWZai2Qlg      about the 7 minute mark for the soil comparison.

Good to hear, mine never went to sleep, just got a bit dozey.