Hi Kitkat & Welcome, I'm going to assume you don't know about these plants, so if I say something which sounds obvious or that you already know, I ask in advance that you pls. excuse me. Xmas cacti are jungle cacti, not desert cacti (as some folks mistake them), so they want & need water. They naturally grow in the branches of trees in the tropics, so in these branches or crotches of trees as they're called, they don't really have soil, just leaves, debris & animal droppings that collect there. Key is that any water runs right through this debris & doesn't stay in the roots long at all. The roots of these plants can look surprisingly small & indignificant. What do you mean by the soil looks like cinder? I don't know that word, does that mean like burnt ashes of firewood as example, like burnt cinders? I agree with statement above that woody growth can be normal, just a sign of older growth, so pls. disregard that. I suggest you take cuttings & start new ones; then repot the old, original plant as well. The leaves are referred to as segments or stems. It's recommended that a cutting should have 3-5 segments on each one cutting. I'd use small plastic pots, & place a number of cuttings around the outer edge of the pot & one or 2 in the center. I just checked my reference book & confirmed that largish plants can be kept in smallish pots, say a plant 12" wide & maybe 8-10" high, could easily remain in a pot only 4-5" in diameter. The mix should be something like African violet soil readily available at nurseries, box stores, etc. w/ added perlite, say 1/3 perlite to 2/3 AV soil. This will make for light & airy mix, fast draining which is what these plants need. Only water the new cuttings lightly as without roots, they can't really take up the water. Give them bright, indirect light or place them at the edge of a window. Either water lightly every few days or spray the top of the mix w/ a plant mister. Pls. don't tug on the cuttings to check for rooting, just wait to see new growth; when you do that means the cuttings have rooted; then you can you can water more. If the original rootball & its mix are hardened, soak them first, in a basin of warm water & crumble off the old mix w/ your fingers as much as you can & repot in a fresh mix. Hope I've covered everything, you should see new growth in 4 weeks I'm guessing, if not before then. Good for you for wanting to rescue & do right by this plant. May it reward you w/ lots of blooms next year. Are the edges of the stems jagged or rounded? Jagged indicates Thanksgiving cactus, rounded indicates Christmas cactus. Good luck!

I am further south than all that have spoken so far so I might not be on topic at all. It got down to 36 last night. That was a surprise so today I started moving some of my pots. Our lows will be bouncing around upper 40's and 50's for the next week. But I move most of my Aloes and cactuses down to a covered stone patio that faces south. The low sun heats it up good during the day and the thick cement columns hold a lot of thermal mass. The slightly cold hardy aloes and cactus love it down there. They get great winter colors and if I get a freak cold front , they are not far from the door to my woodshop. I separate my cactus between who is a tropical cactus (inside now), who takes cold but no damp. who is Zone 9, I will move some in and out for cold fronts, some get indoor perches for the whole winter. Some get covered over outside. It is a mixture of treatments. Now they are just getting moved close to where they are going. God there are a lot of them. Many are cold hardy and don't move at all unless it starts poring rain for many cold days and then I haul them under a overhang..

socks, mine is not unmanageable it's just beautiful even at its size. It is an outside plant year-round on our 15 acres property, compared to other plants and trees we have it not so big in our eyes...

The plant has been in the kitchen window, above the sink, which actually forms a corner, so there's one north-facing window and one west-facing window that come together. The net effect is that the plant gets A LOT of sun every day, albeit behind glass and screens. Once it's outside it'll have to deal with much crazier heat than it's used to indoors, especially if I locate it where it gets as much sun as it's used to--but I think that's probably not the smartest idea. I can keep it sheltered somewhat as noted earlier, i.e., on the covered, shaded patio, but then it won't be getting much sun...which it's definitely used to. You know, I think I might be changing my mind again. I seem to do that a lot after posting here! How does this sound instead of moving it outdoors: put it in a larger pot INDOORS! Keep it in the kitchen window where it's done so well, but just give it a bigger 'house' so to speak.