xmass moss if brown means koyak, should be green like any other plant. but brown doesn't mean the end, be patient and the green moss will grow out in time.
But sometimes it's simply cuz the moss you bought from nature is green on top and brown below,if you manage to transport it as one full piece and slowly open up the piece to plant upright, you'd see green, if like me you mix the piece up and slowly tear clumps to plant, you'll end up with brown bits mixed with green, ie. some are upside down, but doesn't matter . I bought 2 batches from nature, 1st batch didn't plant very well, was brown (upside down) but eventually grew ok. the 2nd batch I learnt my mistake and was more careful in unfolding the mat of moss to plant upright.
Bookmarks