Moon Cactus

[nafeeza_ally]

Hello!

I had this moon cactus for about two years now, but this winter was pretty harsh on my cactus. I brought it indoors, but my house doesn't get enough light (I'm assuming) And recently, the orange part of my cactus started dying. I put it outside because the weather started getting better about a month or two ago, but I noticed it only got worse. So I just left it outside and "forgot" about it because I thought it wasn't savable. I was too lazy too dispose of it, but thankfully I didn't because when I went to check on it last week, I noticed new growth on the side.

Is there anything I can do to get the orange part back on the cactus? What do I do with the new cactus growing on the side? Should I cut off the brown part? I'm a little scared to cut the brown part off because I don't want it dying completely.

Please help!!

[JamesEG]

The orange cactus on the top would have been a different species to the bottom green part, most likely a Gymnocalycium grafted onto a Hylocereus. It looks like it has rotted and is long dead but the remaining green Hylocereus is fine, I would cut off the top until there are no brown areas visible (with a sharp, clean knife), this won't kill the rest of it and will encourage it to produce more branches like the one it has already grown. Hylocereus are quite nice cacti by themselves although they can get fairly large - https://www.google.co.uk/search?q=hyloc ... gQ_AUIBigB" onclick="window.open(this.href);return false;

[nafeeza_ally]

Thank you! I'll cut off the brown areas and see how it goes. Do you think it's possible to graft with the new cactus growing? I read an article where they said you could graft with the new growth, but I'm not sure what to graft with. I have other different types of cacti, but I'm not sure if they would work well with the Hylocereus.

[JamesEG]

Unfortunately I have no experience with grafting so I won't say anything about it in case it's completely wrong! I'm not sure if grafting can be done with older cacti though, I've only ever seen very young seedlings grafted

[hegar]

Moon Cactus is correct. Grafting onto Hylocereus rootstock is done for various reasons, e.g. the grafted plant is not viable like in your case of the "Moon Cactus", which lacks chlorophyll, speeding up growth of very slow growing cacti, or growing cacti that have a very high risk of developing root rot, if planted in the growing medium.
Also, it is true, that you need to graft a plant, that is compatible in size to the Hylocereus. The reason for this is, the requirement to initially match up the phloem and xylem tissues of both plants.
There are videos on the web, which show you, how this kind of horticultural grafting technique is done.

Harald