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[MadPlanter]

A many question series here for you greater cacti peeps!

What in general causes random rot that wasn't started from a point of damage?

If you have rot what are your best defenses?

Cut it out or not to cut it out? Does it mostly pertain to how bad the rot spot is?

Why would a cactus randomly break out in mini to large rot spots all over? It hasn't been watered excessive or anything. It is a regular bridgesii. Had tons of nice roots when it arrived and looked generally good for some time. Now rot, rot, rot, and more...rot all over. To embarrassed for pics...

Another bridgesii "SS" is still totally fine under the same conditions and probably has had more water than the other. The TBMs all get watered often too but no rot on any three of those.

The last standard bridgesii I had in the past suffered the exact same fate no matter what I did or hard I tried. What's the deal?

Thanks for any advice!

[TBM]

Were they all potted using the same soil? Does it smell like rot? I had a similar sounding rot issue with Psychotria nexus before where I had to keep trimming the pieces to save them and rot would return.... turned out it was my doing by using old sour soil.... maybe it's something like that?


I'm not sure what advice I should give though

[nobody]

Sounds like a fungal or bacterial infection (would need pics to be sure). This tends to happen when bridgesii is planted in soil that does not drain well and / or has too much organic matter that is still decomposing. I had the same problem with bridgesii for a while. Kept potting them the same way I do all Trichocereus and that was the problem.

hope this was some help,
nobody

[MadPlanter]

Yes all cactus I have are in a similar custom made mix. Its rot for sure. Its a black and gooy inside the spot before I opened it up to clear some gunk. I have been potting bridgesii just like everything else. Soil probably doesn't drain well enough but then again it isn't watered much. It did probably start not too long after watering it though. The soil its in is pretty sandy and is primarily a cheap potting mix that's less peat based mixed with 50% sand and a bunch of perlite. Same mix works great for all other cactus it seems. I start peyote seeds in the same mix too and it works great. An adult diffusa rotted out in this mix once but other than that only regular bridgesii seems to dislike it.

I have a larger loph w that's in a mix that is primarily the same but has small gravel and a little lime in it. Its been OK in that mix for some time but doesn't seem to grow much. Just hanging in there I guess. The mix over time got so hard its almost like cement lol. Peyote still seems fine in it and water does soak through this mix but I feel its far to hard at the surface at least. Any good ideas on a yote mix? I have looked a lot online but most mixes aren't that far off other than minor ingredients people add. Probably should figure out a better mix for that too before I loose it!

If I need to change the bridgesii mix from the nix I use for pedros etc. What's the stuff I should do different? I don't think there's that much organic matter in the current mix. Not a bunch of woody pieces, peat, or anything.

 Thanks

[nobody]

For adult Lophophora, because of the climate here I use a mix with no soil. 1/3 coarse pea size river sand, 1/3 pumice, 1/3 coarse river sand, and the last third is a 50/50 mix of vermiculite and perlite. I found out the hard way, the hot temps and the long rainy season here leads to rot in soil based mediums. This mix means I usually water once a week in the hot season and once every 3 weeks in the monsoon, have had no rot problems since. For most any potted Lophophora the mix should be one that drains freely, if watered from above it should take no more than 8 - 10 seconds for the water to start pouring (not trickling) from the bottom.

For the bridgesii, I use the same base mix as with all my other Trichocereus (mostly potting soil and river sand) and mix it 50/50 with pumice. I have not had any rot with this medium in a few years of using it.

The root system on bridgesii seems a bit more sensitive than with other Trichocereus, mine really disliked fine sand.

nobody

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[happyconcacti]

Does it look like this?

If so, an old-timer cactus grower told me his theory of how these spots form. He said that Trich's (in my area) are particularly susceptible to it during colder temps  (40's to 50's) and when humidity is in the 40% - 60% range.

As far as recovery goes, I just leave em. Yes, they make for crappy looking cacti but in the long run, they seem to heal up nicely and not be bothered.

For prevention, the old-timer recommended spraying them with VERY dilute mixture of bleach water when you know the temps are going to be low with "high" humidity. I have not tried this but it would be good to know for us all.

I'll definitely be taking Nobody's advice and trying a faster draining soil with the bridgesii. It's difficult though because I live in an incredibly dry environment, for the most part, and getting enough water to Trichs is the biggest concern.

Also, more spots tend to show up after a few days of getting bridgesii in the mail. Anywhere the skin has been damaged (i.e. by other spines), the spots will form there as well.

I'll dig around on another forum, I've seen more information on exactly this problem.

The first two pictures, you can see what older spots of infection start to look like.

In the third picture, there's a new infection on top and a more healed one below.

1 Like MadPlanter likes this.

[New Wisdom]

Bridgesii are extremely prone to getting black spots, scars, pits, ect...  They are harmless 95% of the time and is just natural scaring due to environmental issues.  You see it in penis plants and bridgesii alike.  You don't want to go cutting on them whenever you see spots of black or tan unless it starts to get squishy and has a large area.  Trichs in general will sometimes get harmless black spots as well.  When I first started growing I flipped out over some black spots on my T. pachanoi.  I stopped feeding, watering, and I even took a knife to them.   I ended up harming them more than the black spots did since I later learned there was no harm being done.

If the spots are actually rot or they are squishy there are a few things you can do.   Slow down watering. Find a less humid spot. Dust sulfur powder on the infected areas.  If it starts to become a very large area that looks like it might take out the whole plant you can start cutting.  Some people recommend just to leave them alone and see what happens, but if it is something you don't want to loose then you can chop out the infected areas and dust with sulfur.  If it is so bad it's all the way through the plant you can chop it up into several cuttings, but remember to dust any open wounds with sulfur to stop the spread.  A lot of the time rot will start in the roots. If that happens then you're pretty much screwed a lot of the time.  Because even if you try to cut it out it will come back through the vascular cambium. 

Personally I have just been leaving plants alone that are rotting.  Not taking the knife to them.  I will dust the plant with sulfur and stop watering for a bit, but that's it.  Sometimes it's best just to let the plant's immune system take care of itself.

New Wisdom

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[happyconcacti]

Oh, and another way that I've caused black tips:

Once I had brand new cuttings, potted them, the got "distracted" for a few hours and left them in direct sunlight. The tips burned badly. At this point, the skin became squishy and had clear liquid oozing out wherever I squeezed the skin.

They I made another mistake in my state of panic & confusion: I took them inside, pulled them out of the soil, and placed them tip-down in a box. The next morning, I pulled them out and they all had black tips.

Eventually, they healed, scarred over, and were left with thick brown skin where the tips had been blackened. New growth came out of the tips and left scars on about a 2" length of the columns. Unfortunately, I didn't take pictures of this string of incredibly stupid mistakes.

Hcc

EDIT: I also sunburned the tip of a T. pascana and it turned black. The spots didn't form on the rest of the cactus luckily and it recovered nicely as well.

[TBM]

I've had black spots form on a T. bridgesii just from poorly transplanting it, I had the pot the cactus was in on it's side and I was slowly moving soil away from the roots to loosen everything up when the whole thing quickly dumped out unexpectedly causing the cactus to get buried upside down in the soil I was trying to uncover it out of. The cactus itself actually got a little bit bent from it and it started to show bruises/black spots all over the one side, but they haven't spread at all since then so I don't worry about the blemishes, it seems like all it needed was time to heal.

[MadPlanter]

HCC that is pretty much exactly what's happening! One spot is really bad and has probably compromised the mid section of part of the cactus which is fairly tall. May have gotten through the whole vascular ring but idk for sure. Its probably way too humid where it is and maybe it would help to move it. I'll try and move it to a dryer location and leave it be. Seems like everybody seconds leaving them be so I'll just let it chill.

Thanks all you guys for the input!

1 Like happyconcacti likes this.

[MadPlanter]

Well a bad story got even worse. When you guys were saying humidity could possibly cause the rot issues I ran out to the greenhouse to put the cactus outside because its humid in there. I hadn't rained for days so I just stuck it out in the yard not expecting rain. Now its pouring balls on the cactus! Can't catch a break with these bridgesii! Its probably gonna rot even faster now that its soggy wet...damn.