Mangroves don't always grow on mud
I was messing with mangroves and noticed they don't seem to consistently grow on mud.
working:

not working:

Even with the random tickspeed up and the same sized platform, it doesn't seem to grow. The second grew without issue once I turned the platform to grass blocks using /fill.
More tests may need to be done to see if there is an exact reason that I haven't pin pointed yet, but currently this seems wrong.
Linked Issues
Created Issue:
Mangroves don't always grow on mud
I was messing with mangroves and noticed they don't seem to consistently grow on mud.
working:
![]()
not working:
![]()
Even with the random tickspeed up and the same sized platform, it doesn't seem to grow. The second grew without issue once I turned the platform to grass blocks using /fill.
More tests may need to be done to see if there is an exact reason that I haven't pin pointed yet, but currently this seems wrong.
is duplicated by
Does MC-250070 describe your issue?
Thank you for your report!
We're tracking this issue as MC-250070, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as Won't Fix, which means this is considered a bug but won't be fixed. The description of that ticket or the comments might explain the rationale. Please do not leave a comment on the linked ticket.
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Does MC-250070 describe your issue?
I was unable to reproduce this in either a normal or superflat world, is the build in the screenshot of an elevated/raised platform? See MC-250070

I did more testing and believe I have learned something of value. A solid block must be beneath the mud (not even necessarily directly below (but it can be), a small gap seems to work as well). My guess is this has to do with how it grows and replaces mud with muddy mangrove roots. I assumed the roots stopped at the mud and then replaced mud with muddy roots, but they actually grow through it, replacing what they pass through. This means this behavior may be intended.
Sometimes even when there are solid blocks underneath the mud, the propagule fails to grow.
This has more to do with how the roots detect a proper 'stopping' place. The mud itself is not detected as a 'stopping' place because, as Sniper1.1 says, it can be replaced with muddy roots instead. There also needs to be room for the roots to grow properly out in horizontal directions, which sometimes fails on platforms or ledges, like this. I don't think this is a bug, but rather just very picky tree gen.