My dead astrophytum

[Shim]

Hi buddies,
I'm a beginner but cactus lover in South Korea and I have my small cactus collections.
Summer is just started here and I found one of my Astrophytum was dead a day ago.

I had experience in dead cactus but I haven't seen like it.
I bought it from online shop in Italy last winter and one thing I worry about is that it arrived in dead.
It took a month to ship and didn't look dead at that time, though.

I potted them 5 months ago but root hasn't grown as you can see from the picture.

Can any body identify the cause of its death and advice me how to prevent it for future?

Thank you.

[Salazar]

I'm not sure but it could be frost damage since you ordered it in winter.

[hegar]

Well, by looking at your images, your plant died because of a "root rot". This is most often caused by overwatering the plant. I do have quite some experience with this condition, because most of my plants that died expired because of this reason.
The plant does look fine one day, and a few days later you notice a color change. By the time you notice that change, the plant is usually already gone, because the rot organism has spread throughout the cactus.
The genus Astrophytum seems to be more susceptible to root rot than some other cactus genera. Do not be too upset, because having some plants die happens also to somewhat experienced cactus hobbyists. If I can ever figure out, how to prevent this problem, I shall definitely post recipe here on CactiGuide.

Harald

[Shim]

Thank you for the comments.
It might be 'root rot' or 'frost damage' since I potted them early in January and watered them last February.
I should have been more patient and ordered them in Spring. I'll looking forward to your posting.