Moss, of course

I’m considering top dressing my bonsai trees with moss. Good idea or mistake?

Understand the benefits are that moss keeps tree roots cooler in summer, encourages greater root growth in the top layer of soil, and provides better retention of water near the surface.

Is this a good idea for all bonsai or just selected species? Assuming a moss surface is desirable, I prefer tight moss such as Kyoto Moss, which seems to absorb water well rather than force it to run off. Is there any source to obtain sheets of Kyoto moss (or something similar) or should I try growing it using Kyoto Moss Spores, which are readily available for sale? I understand the process is slow.

Or, is it best to use moss from the garden, though there are many kinds to choose from. To create a moss surface, a trusted source suggested I combine shredded live moss collected from my garden with shredded sphagnum moss, moisten and place on top of my bonsai mix at the soil surface. Was told over time the moss will grow/spread.

Which approach is best?

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Was this trusted source named Ryan Neil? :joy:. There’s a video in the archive called top dressing creation, I believe is the name of it. You should look it up and watch it. But yea get sphagnum moss and shred it up. Collect some living moss, look for it on agregate surfaces like concrete, rock, asphalt. These surfaces are the most similar to bonsai soil so you know you will be collecting species of moss that will grow well. Mix some of the live moss into the shredded sphagnum, apply it to your soil surface dry, it’s easier to just sprinkle on than trying to get it wet first and put it on in clumps.

You really don’t need a ton of live moss to get moss to grow. Actually a lot of time, if I have a lot of repotting to do, I will just put sphagnum on first. As this functionally does the job. And then later on I will come back and sprinkle living moss, not even that much, into the surface of the sphagnum. A month later i’ve got a pot covered with moss. :sunglasses:

Try not to over think it. The sphagnum is the most important part of the equation for functionality. Don’t bother with Kyoto moss, there’s plenty of lovely native moss species that will do the job with one tenth of the effort and time put in.


I highly recomment the stream “spring fundamentals” for this purpose. Ryan discuss the use, benefit and limits of moss in detail.


Wish I could watch it, but I am not tier three! I agree with using moss collected on an aggregate. I have had best luck with moss from brick sidewalk or landscape stone and walkways.
I mix the sphagnum and collected moss while dry, and apply it to the surface, then lightly water to moisten the dressing and then once wetted, water the tree very thoroughly.:nerd_face:
. Good advice from experienced practitioners. I love the forum :heart_eyes:

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I collect a large tray of moss in the spring from any SHORT growing clean spot. Dry and break it up into small chunks (sieve). Spores. Rub the sphagnum through a 1/2" sieve, leave it largish chunks. Mix. Sprinkle. Grows moss OK. Usually dries out in heat of summer / dry days.
Have always used top dressing. Have always kept moss on most smaller bonsai for moisture. Not completely covering.
Will sometimes transplant thumbsized chunks of live moss. Grows moss faster. Use tweezers. Trick is the top dressing , pushing the moss INTO the surface soil, and water in. Just laying large plates of moss on the surface doesn’t look natural.


the "spring fundamentials stream is for free on you tube!

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Thank you one and all for reinforcing what I sensed was the better approach, and for reminding me that Ryan had touched upon this subject in “Spring Fundamentals”. He was not the trusted source I referred to. Had he been that person , I would have no reason to post since I trust his knowledge implicitly.

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Necro-post! All of these were potted this year, so here’s about half a year’s worth of development.

Here are three trees I experimented this year. I collected moss from my neighborhood, shredded it in to small chunks and let it dry for a week in my garage. Then I mixed in shredded died sphagnum. It was about a 60/40 mix, mostly sphagnum. I then put it all in to a blender I bought as a garage sale. I spin it for about 2 minutes and it was almost a powder.

note on died sphagnum. I shredded up a couple quarts of sphagnum moss, then added about a table spoon of sumi ink I purchased on amazon.

First pic was planted in May. Second pic was planted in July. Third tree had moss already, but I added a good handful of the powder I made. It’s super lush!


Dang, looks like pulverizing the mix really worked! Oh, and you’re also in Seattle. Here in SC I’m counting my lucky stars and super thankful that I got any moss lol.

It struggled in the summer. But, as soon as the rains came it sprang to life!

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My moss generally dies in the summer here in Portland, but comes back pretty quickly.

One thing I have found, moss that is grown in the above way comes back quicker than collected moss placed right on the surface (like for show prep or something). I think it’s mostly because the adhesion to the soil is much better when the moss is grown in place, and thus makes the moss much healthier and more likely to bounce back.

I grate my moss and sphagnum through a 1/4" screen. Haven’t really tried placing pieces of moss. Isn’t that more of an action to take just before a show?

Yeah and it’s not ideal to leave it on your trees long in my opinion. It never seems to last.

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What’s going on when moss turns black? I have a juniper that had lush moss in the spring. It seems that over the summer, the side that was more shaded has turned black. The rest is still a nice vivid green.

On other trees where moss hasn’t thrived so well, it’s more dry-looking and brown, but this seems different. Maybe it was too wet in the shade? I have rotated it so it is now facing the sun and it is now sort of crispy but still very dark in color.