I got one of those little grafted cacti, you know, with the colored tops and triangle shaped stems. I was looking through a selection of them when I saw a black one. The stem wasn't black, just the colored top. It looks perfectly healthy, and it's in great condition, but, I think I need a proffesional's help... Is the top supposed to be black on some?
Oh good... This is really strange. Look at this: the center of my cactus's stem shriveled up to a straw-like thing, then completely shriveled, even though I had been watering it regularly. I still water it, and it seems like it's still alive, but how is that possible? It's still standing up straight, but... It was really weird. Any ideas on what happened?
Turned out it was dying. No, I was making sure I didn't overwater, but it died. Wish I could get another...
the top part is a gymnocalycium mihanovichii. most are red/orange/yellow and they're grafted onto another type of cactus because they don't have the ability to do photosynthesis (they have no chlorphyl) so they can't grow on their own. there are varieties that are green or purple. and black, if you say what you had was black... those types can successfully be grown on their own roots (they have chlorphyl) given time. this type grows very slowly, though and that's mostly the reason they are grafted - so that they can grow a little more quickly. the root stock tends to rot easily to begin with and most people tend to over water, so you end up with what you have/had. a pretty plant that's dead. the other thing is that the nursery places use peat (it's cheaper and easier for them) and that is really, really, really bad for any type of cactus. once it dries out, it's virtually impossible to re-moisten it and, even though cacti need dry conditions, once that stuff dries out it's like concrete and any water you give the plant will not get to the roots - it just drains off to the side. so, you did the correct thing by not overwatering it...being in the peat that had dried out, any water you gave wouldn't do a thing. it's a shame that it died...although, if it's just the bottom part that is all shriveled you may be able to salvage the top piece by cutting off the root stock and attempting to root it. if you still have it, cut off as much of the root stock as you can and then let it dry for about a week and then pop it into some cactus soil mixed with perlite or small stones. don't water for a couple of weeks and then give it a drink...you might get lucky! i really wish the nursery places wouldn't use peat!! anyhoo, it's a lesson learned. sad as they're such cool plants. you WILL see them again and you can get another. when you do, first thing is to repot it in cactus soil mixed with perlite or small stones. water sparingly in winter (no more than once a month, if even that) and then water about every 3 weeks during the summer growing season. i've never seen a black one - i'll bet that looked really cool!! i did find a purple one at halloween...advertised as 'jack-o-lantern cactus'. so, of course i had to get it!
I would try that... but by now, that plant could be anywhere. It seems to have disappeared. I used to have some cactus soil... I don't know if I still have some, but I'll look for another cactus with a black top... When I find one, I'll take pics. And of course, I'll be sure to transplant it.
