Whitesloanea Crassa - black spots, squishy

[kal9988]

This Whitesloanea Crassa was in the mail for 1-2 weeks. It has black spots at the base, and the bottom portion is a bit squishy. However, the base (the part with the spots) feels solid, it's just the area above it that's squishy. Is this rot or just being in the mail?

[Aiko]

I know Larryleachia and Pseudolithos can become very squisky when they are very dehydrated. I have less experience with Whitesloanea, but I would not be surprised if they have the same tendencie when dried out. Although it should be the whole body that is soft and squisky, not just the bottom part.

Well, if it is rot, you will soon find out, as it will probably rot at great speed. But I doubt it would rot just for being in the mail for two weeks.

[kal9988]

Thanks! The whole body is soft, just the bottom half is more so than the top. I'm hoping the black spots are not a problem. I just potted it and I'll wait a week then give it a DROP of water bec. I know these are not meant to get much water during the winter.

[Aiko]

I don't know how literaly you mean 'drop'. But I would go for a light splash. They are (should be) warm after all, so need regularly a bit of water or they dehydrate too much. The water should be able to reach the roots. But also dry out again quickly. Nice balancing...

[kal9988]

By a drop of water, I meant enough to get the roots wet. It's in a 65% pumice/perlite mix, so it's pretty fast draining.

The plant feels more solid after a few days in the soil (no watering yet), so I'm hopeful rot is not the problem. I want to spray fungicide on the black spots to be safe, but which fungicide should I get? I have seen different ingredients in products: Copper Fungicide, Neem Oil Fungicide, Sulfur Fungicide, or something else?

[greenknight]

Fungicides only prevent fungus, if your plants have a fungus infection already they won't help.

[kal9988]

How do you deal with fungus then?

[greenknight]

They only way to get rid of it is cut it off. The black spots may not be fungus, though, or they might be a fungus that won't spread. There are fungi that produce dry black patches of dead tissue which cacti are able to wall off and stop from spreading. The fungus produces a crop of spores and dies, the plant can survive indefinitely with those dead patches. Whether this can affect Asclepiads, I don't know.

I don't know if you can cut and re-root these plants, either, but I doubt it would survive that - only as a last resort would I try it. If those spots aren't mushy, I'd just watch and wait.

[kal9988]

The rot took it

[BarryRice]

So you were asking about how we grow the plants at UCDavis. It's not like our Whitesloanea are award winners, but we do keep them well, and they occasionally flower for us.

The biggest observation we have is that, while we give it bright light year-round in general conditions that work for many other sensitive plants, we don't let it dry out quite as completely between waterings as many other succulents. Yes, the medium is very well-draining, and the air circulation in our large greenhouse is great, and the lighting is uniform. We don't like the temperature to drop below 70F, or even 75F.

Just some thoughts.

I think that, if you got a plant with black soft spots on it, your plant was doomed from the beginning....

B

[kal9988]

Thanks, Barry! You're right, I'm pretty sure the black spots were fungus. Any chance you could post the photos of the UCDavis Whitesloanea's?

[BarryRice]

Sure, but it will take a few days before I can get to the collection.

[kal9988]

Sounds good.