Hi Mithander,

Sorry, there's so much going on w/ this plant. Fungus gnats are generally indicators of too much watering.

These plants are jungle cacti, not arid cacti, so they do need water w/ reasonable frequency & are designed to tolerate the extreme heat of the tropics. (They originally hail from Rio de Janeiro, Brazil which is where I grew up, so I know they have rainy season in January & that it gets VERY hot.) But that said, they need fast draining mix 'cause their roots can rot quite easily.

Yes, flowering is a lot of work for the plant, but generally one withholds water for one month after flowering & then the plant slowly starts to come back. Usually mine start putting on new growth again in March or April & I resume a regular watering schedule.

Maybe the soil you used had wetting agents in it? If you still have the package maybe read the list of ingredients.

At any rate, soil that's too wet & then a a plant moved to a pot that's too big combine to make for conditions for rot. Also putting it into a cooler room combined w/ damp soil can also lead to serious rot & root rot (that's why you have fewer roots).

These plants normally grow up in the crotches of trees w/very little mix & just whatever leaf debris & animal wastes happen to drop on them. Their natural habitat gets lots of rain, sometimes frequent rain (depending on the season).

Sorry, but if a plant stays too wet, the last thing to do is water it more. Does the pot still have drainage holes? 'cause this is in part a bad drainage problem.

I'd put it back into the smaller pot, into a mix of 1/2 African violet soil & half perlite or pumice. I'd smell the roots for rot & then sprinkle ordinary cinnamon (like you use for baking, actual to prevent rot) on the roots & then shake them off & pot up as above.

I'd put the newly repotted plant into a position of bright, indirect light & then please leave the plant alone.

These plants thrive w/ benign neglect & when healthy, a bit of fertilizer. They tend not to do well when fussed over. I realize you're trying to help the plant, but you're killing it w/ kindness & not resolving the basic problem which sounds to be bad mix, compounded by too much water & then maybe also cold, air conditioned air.

While you wait for it to recover you can check out your other cuttings which you mentioned are growing well & also read lots of Christmas Cactus posts here at C&S. Good luck!

Pirate girl offers some good tips on the culture of this plant.

I think, most importantly, you need to change out the current peat-based soil mix.
Because these are jungle cacti, growing in the crooks of trees in various leaf debris,
I have the most success growing them in a mix that is mostly bark - Orchid Bark, fine-grade.
You can grow Christmas Cactus in pure bark, or you can add perlite, pumice, even a small amount
of bagged soil - I would use Orchid Mix because of its bark content, but in the past I have
used African Violet mix, as well. I don't mean to contradict Pirate girl in any way.....
As they say, There's more than one way to skin a cat.

Good luck, and let us know how it goes.

Josh

Thank you both for the great suggestions. Your replies were very prompt, unfortunately the email notifications weren't working and I didn't think to check back to the actual page until September! Anyway, at that time I moved the plant back to an even smaller pot than before, rinsing the roots well and sprinkling them with cinnamon before potting them in a mixture of Orchid Mix and perlite. I moved it closer to a sunny window and we kept it in the living room through the winter (so it didn't have the proper lighting to flower again). The plant perked up within a few weeks, with healthy green leaves again, and no more gnats! Thanks so much for your help, I will always be potting my Christmas Cacti in Orchid Mix/perlite from now on! And another happy note, the cuttings from leaves that fell when I first repotted it were doing so well that they flowered this winter!

{{gwi:561579}}
Much happier cactus (right) and thriving cuttings (left)

{{gwi:561580}}
Flowering cuttings and Marble the cat

Welcome back! That's great news!

By the way, this is actually the Thanksgiving Cactus, Schlumbergera truncata.

Josh

Hey Mith,

How nice to hear, thanks for coming back to let us know. I'm sure I speak for Josh as well, in saying it's always nice to hear when folks come back to thank us for our help & report their plants have improved for it. Good going.

That bloom color is pretty spectacular, the cat's not bad either ;>). Enjoy!