Identifying rot

[SpriteFish]

I've recently been given alot of neglected succulents, and have trying to repot them while also looking for potential diseases. Because these plants have been so stressed and nutrient starved, they're turning all sorts of differnt colors, even ones I didnt know could change colors! (One of the hairy cacti was red/pink for some reason)

The color change has actually been making harder to tell if their rotten. What I mean by this is, for example, I was unpotting and trimming a fan aloe that was partly red due to stress, and cut part of it as I suspected rot. When I cut the plant, the inside was red aswell, and I'm unsure if this is just the stress coloring or if it's rot?

I found one plant that was mushy and felt very rotten as it easily broke apart, yet it was white on the inside. A few of the plants were yellow on the inside, and I'm not 100% sure if these colors indicate rot or it they could be saved.

Of course once again this will be something I have to experiment with myself, but I was hoping people here would have some knowledge about whether these colors represent rot or not, or other ways to spot rot.



Just an interesting side note: I had unpotted all of these plants, and had put off repotting them for awhile (about 4 weeks). Coming back to them it looks like their roots have dried alot, so hopefully I'll be able to restore them, but I also noticed the root mealybugs that were once there are gone now, so that's something.

[Steve Johnson]

There are 2 types of rot -- black and orange. For example, this is an Echinocereus rigidissimus rubispinus that rotted on me in July 2012:

Echinocereus_rigidissimus_var_rubispinus_rot_07152012.jpg (127.18 KiB) Viewed 885 times

The plant rotted from the inside out -- that's black rot on the left. Now for an example of orange rot -- this Turbinicarpus polaskii was my current collection's first casualty when it rotted (also from the inside out) in October 2011:

Turbinicarpus_polaskii10312011_01.jpg (171.76 KiB) Viewed 885 times

Without being able to actually see photos of your plants the way they look now, the plant that was mushy may be the only one that rotted, although white on the inside usually indicates mold. One way to tell if you have rot -- when cacti and succulents smell like mushrooms.

[SpriteFish]

Alright I've taken some photos of the succulents and cacti I cut, to give a better idea of what the inside looks like. Next time I should cut then vertically if im nkt worried about growing it if its ok, may give a better view of rot. Also, I have now realized that this topic may better fit in thensick cacti catsgory (not sure why I didnt realize that sooner), so if this topic needs to be moved just let me know.

I will try to organize the photos, but it will likely not be in order consistently:

. Mushy clustering cacti that is white on the inside (also it had tiny red fuzzy balls on it for some reason)

. Weird looking rossette succulent, the leaves are kind of translucent so I would think it had too much water? It is yellowish on the inside.

. And finally, a fan aloe I cut a leaf off. It is red and green on the inside

. I also threw in a photo of I think a harworthia, which is pink on the inside yet is green (and a little red) on the outside.



There's I good chance that I have cut preemptively, and prepaphs they were OK after all, in which case I could try rooting the cuttings.

[Steve Johnson]

... I have now realized that this topic may better fit in the sick cacti category (not sure why I didn't realize that sooner), so if this topic needs to be moved just let me know.

Yep, your thread should be in the Sick Cacti forum, so I moved it over there for you. We need as much detail as possible, so please post close-up photos of each plant. And sorry to be Mr. Picky-Fussy, but...

1 cactus plant = cactus (singular), 2 or more = cacti (plural).

[SpriteFish]

We need as much detail as possible, so please post close-up photos of each plant. And sorry to be Mr. Picky-Fussy, but...

1 cactus plant = cactus (singular), 2 or more = cacti (plural).

Are the pictures I posted alright or do I need to get some better ones?

Also fair point about the cactus cacti differnces, I autopiloted calling a clustering cactus cacti, even though it is still one singular cactus!

[Steve Johnson]

Are the pictures I posted alright or do I need to get some better ones?

Take the photos you have on your computer or Smartphone, and crop each one down so that the plant fills the frame with a small margin all the way around it. When you post the cropped photos, it'll be easier for us to get a detailed view of the plant. I'm pretty good with Photoshop -- when I download the photos you post, I can do some enhancements and repost them.

[Ilvin]

None of those plants look rotten to me, but it is a bit hard to tell from the photos. I've lost plants to rot before and in every case it was obvious and progressed really fast - they all went brown and mushy. I haven't seen a cactus be quite as white as the top one though.

[SpriteFish]

Yeah I probably jumped the gun and assumed rot way too fast. Although, that mushy cactus is really weird, I wonder if I'm confusing the feeling of mushy rotten cactus with how a cactus feels while really dehydrated (they arent quite as firm). I did save a good looking piece of the mushy cactus, so if it's not rot it should grow. I could also try to root some of the cuttings I took.

I took some better photos, although unfortunately my camera sucks so these are the best I can do. I also cut a peice of the mushy cactus vertically to get a better view. R.I.P the cactus, but I did save a peice that should be able to grow.

The rossete one I swear looks overwatered, due to yellowish leaves and transparency, I'm curious what you all think of it. Also I'm very confused why one of them had pinkish red flesh on the inside.

[Steve Johnson]

Those photos are better. And I agree with Ilvin -- none of the plants appear to be rotten, although I do kinda wonder about the mushy cactus. Pink flesh on the base is typical of some Mammillaria species, but that's not what you have. Do we see this with non-Mammillaria species? Unfortunately I don't know, but if you see pinkish flesh on the good-looking piece, I wouldn't worry about that -- try rooting it.

See this for more information on rot:

https://www.cactiguide.com/cactipests/#rot

[Steve Johnson]

Hi SpriteFish,

I just wanted to follow up with you on a couple of related things...

When you take images on your Smartphone, go to the Gallery app and click on the photo. Click on the upper right corner of the screen -- this gives you a drop-down list of options including the Crop tool. Click on Crop and use your finger to move the left, right, top, and bottom borders so that you have a small margin around the plant without cropping out parts of the plant. Then click on Done -- you'll have both the original pic and the cropped pic in your Gallery. Here's an example:

20241102_161245_copy_345x768.jpg (78.8 KiB) Viewed 770 times

That's your original photo and what you would've gotten if you cropped it in your Gallery app. As we can see, there's much more detail in the cropped photo, so it's best if you crop your plant pics before you post them on the forum. Which brings me to the other thing...

Plant identification is really important for a couple of reasons:

• Cacti -- genus and species of the cactus tell the grower a few things. First, most genera are easy to grow, but some aren't for beginners. Even within a given genus, most species are easy, while there may be species that'll give beginning growers a hard time. A good example is Astrophytm -- capricorne, myriostigma, and ornatum are easy, but A. asterias requires some experience to keep it alive and growing well over the course of more than a year or two. Second, this gives us an idea regarding the growth rate that's normal for the species of cacti being grown -- some are fast growers, some are slow growers, and a few have growth rates that are positively glacial. (The slowest is Aztekium ritteri with a normal growth rate of 1 mm per year!) And third, it tells the grower about the plant's type of root system:
  
  https://succulentalley.com/cactus-root-systems/
  
  Know the genus and species, know what type of root system it has, and growers will be able to determine the correct pot size for the plant. By the way -- while that article is generally useful, I do disagree with what it said about "Cutting into this natural root cycle should only be considered as a last resort and requires careful consideration." When cacti become root-bound, there's nothing at all wrong with judicious pruning of the feeder roots unless the cactus is old.

• Succulents -- proper plant ID tells growers which of their succulents are summer growing-winter dormant and winter growing-summer dormant. Once the grower knows the genus, he or she can use this handy guide:
  
  https://www.succulentsandsunshine.com/s ... ncy-table/
  
  (The "Grow mostly in spring, summer and fall" list includes cacti.) I used to grow succulents in my younger days, and I found them to be generally easy. The only exception -- Lithops, which I could never figure out. Beginners trying to grow Lithops are in for a challenge, but they'll get a leg up with advice coming from more experienced members on the forum.

I'm assuming that the cacti and succulents you have in your collection didn't come with plant name tags. If that's the case (or the tags are gone and you can't remember the names), you can post cropped photos in the Cacti Identification and Succulent Identification forums:

https://www.cactiguide.com/forum/viewforum.php?f=3

https://www.cactiguide.com/forum/viewforum.php?f=10

I get Aiko's reasoning behind why members should do some basic research before they post, so his ID rules for posting include a couple of links that'll help without you having to spend a whole lot of time on it. But if you'd like to dig deeper, try this:

http://www.llifle.com/Encyclopedia/CACTI/Genus/

http://www.llifle.com/Encyclopedia/SUCCULENTS/Genus/

When members respond with IDs for your plants, knowing their names will come in handy as you learn more about the best practices for growing them well under your local conditions.