Gymnocalycium mihanovichi v. rysanekianum turning colors

[WayneByerly]

My Gymnocalycium mihanovichi v. rysanekianum used to be green ... with just the slightest hints of color. Recently It began color changes that I cannot help but feel are extreme. Despite the fact that I've read that this particular genus is known for it's spectacular colors. The picture included below is quite accurately depictive of this cacti's coloration.

Can anyone tell me whether or not this is normal coloration? Or have I done something to it?

DSCF3089.jpg (79.67 KiB) Viewed 5473 times

[teo]

They do get 'tanned' in sunshine - This has a bit more color than mine - but you might have more sunshine than me.

[Steve Johnson]

My Gymnocalycium mihanovichi v. rysanekianum used to be green ... with just the slightest hints of color. Recently It began color changes that I cannot help but feel are extreme. Despite the fact that I've read that this particular genus is known for it's spectacular colors. The picture included below is quite accurately depictive of this cacti's coloration.

Can anyone tell me whether or not this is normal coloration? Or have I done something to it?

Teo is correct about the "suntan" effect on certain Gymno species, although it can be exacerbated by stress if they don't get enough water. Yours looks pretty thirsty, but after the plant starts plumping up and gets water on a regular basis, you'll see the skin taking back a proper amount of its green coloration. If you're interested, I'll post up a few comparison photos of my Gymno stenopleurum which will show you the changes it goes through during different times of year. Its growing behavior is quite similar to mihanovichii, so I think these photos would be instructive.

[WayneByerly]

If you're interested, I'll post up a few comparison photos of my Gymno stenopleurum which will show you the changes it goes through during different times of year.

THAT would be enticingly instructive ... and I would be TRULY interested in seeing whatever you have to say/post/show/share.

Thanx.

[Saxicola]

Take a look at this thread. I posted originally mostly to show an unusual bloom coming from the base of the plant, but it turned into a discussion similar to yours. You can see the difference the plant showed between the shady times of year and the sunny ones. I've moved since then and my yard is much sunnier, so now it stays that nice orange-red all the time. The exact species of Gymnocalycium is different but the concept is the same.

By the way, I sell the plant you have on eBay periodically and they look almost identical in shape and coloration. So I think yours is just fine.

viewtopic.php?f=2&t=27255&p=240867&hili ... um#p240867" onclick="window.open(this.href);return false;

[Steve Johnson]

Take a look at this thread. I posted originally mostly to show an unusual bloom coming from the base of the plant, but it turned into a discussion similar to yours. You can see the difference the plant showed between the shady times of year and the sunny ones. I've moved since then and my yard is much sunnier, so now it stays that nice orange-red all the time. The exact species of Gymnocalycium is different but the concept is the same.

By the way, I sell the plant you have on eBay periodically and they look almost identical in shape and coloration. So I think yours is just fine.

viewtopic.php?f=2&t=27255&p=240867&hili ... um#p240867" onclick="window.open(this.href);return false;

Saxi has the subject pretty well covered in that link, although you might enjoy viewing the seasonal changes my Gymno stenopleurum goes through...

Here it was in August 2012, about a month after I received it from CoronaCactus:



From early March last year, coming out of its winter dormancy:



At the end of July, after regular applications of water and fertilizer through spring and summer:



As the cycle repeats going through another period of winter dormancy, here from 3 months ago:



And finally, the view from today:



The behavior of the species is totally normal here, so the similarities between stenopleurum and mihanovichii should be pretty obvious in terms of what you can expect with your Gymno throughout the different seasons of the year.

[hegar]

I do agree with Saxicola and Steve Johnson about stress-related color changes of the epidermis of some cacti. I do have a cactus (see photo), which I call my "purple pentalophus" (Echinocereus pentalophus), which almost year round shows no green color anywhere on its stems. The only exception is the new growth, including flower buds. This plant is in the ground and the purple coloration is due to cold weather during the winter months and excessive sunlight and heat during the warmer part of the year.
I also concur with Steve about the plant being "thirsty". Did you water/fertilize it and did it plump up? If not, there may be something wrong with the root system of your cactus, perhaps it has rotted away.
I do not know, if your kind of cactus should be grown in very bright light or if filtered light would be better for it and its color retention.
Cacti, at least the desert varieties, are grown with a good amount of light, but greenhouses often do use shade cloths to keep the plants very vigorous and healthy looking. If you do not match this kind of environment, the plant may go into shock. I have actually killed a few plants within a day or so by just planting them in full sun without providing any shade. Sometimes, moving the plant into a spot that does have less light will make the cactus to green up. However, too little light will lead to etiolation (thinning, spindly growth) and pale green color. Also, flowering under those circumstances is less likely or will not happen at all.

Harald

[WayneByerly]

Heartfelt thanks to Saxicola, Steve Johnson and Hegar. It is a shining approbation on your character that you have taken your own valuable time to try to help someone else. Thanks

The condition of the G. mihanovichi has progressed. It now looks like this:

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DSCF3298.jpg (43.44 KiB) Viewed 5375 times

[WayneByerly]

... there may be something wrong with the root system of your cactus, perhaps it has rotted away.

The comment about the root system made sense to me. So I decanted the cactus, and found that it's root system while appearing to be fairly healthy, was nearly non-existent. The whole root system was only about an inch long. The individual roots were tight together and very firm. Just very short. So, believing that it might be saved, I treated the roots with a dry powder root hormone (Rootone Rooting Hormone with Fungicide) and replanted it.

I guess we'll see what happens this summer.

[Steve Johnson]

... there may be something wrong with the root system of your cactus, perhaps it has rotted away.

The comment about the root system made sense to me. So I decanted the cactus, and found that it's root system while appearing to be fairly healthy, was nearly non-existent. The whole root system was only about an inch long. The individual roots were tight together and very firm. Just very short. So, believing that it might be saved, I treated the roots with a dry powder root hormone (Rootone Rooting Hormone with Fungicide) and replanted it.

I guess we'll see what happens this summer.

Okay, now would be a good time to give you some understanding of basic cactus behavior...

If you could peer into the soil of desert cacti, you'd see that when the roots are dry they appear to be dead. Then when these plants get watered, the roots suddenly grow a multitude of very fine root hairs -- it's the transport mechanism that gets water and nutrients to the plant. The constant cycle of dying-off and regeneration of the root hairs is part and parcel of their adaptation to the harsh, arid environment of the desert. Misguided hobbyists insist that their desert cacti should have some degree of moisture in the pot at all times during the growing season. This simply isn't true. Many species are tolerant enough to take it, but the roots of your mihanovichii will be much more responsive to rebuilding a healthy root system if you let the mix dry out thoroughly between waterings. I know it seems counterintuitive, although if you're patient about resisting the temptation to water more often than what the roots need for proper growth, I think you'll see a nice turnaround in summer.

[keithp2012]

I have the same situation happen and it doesn't seem to bother the cactus health wise. More sun tans it up. http://www.cactiguide.com/forum/viewtop ... ii#p312317" onclick="window.open(this.href);return false;

[cactushobbyman]

Mine are even darker. The Central Valley sun and heat. But flower with no problems.