Perlite as Pumice in a bonsai mix

[Clicio]

Yes you can! I've had little issue with the floating, I mean yes it will tend to 'rise' to the top in the highest inch or two of substrate but this isn't anything that bothers me as I'm developing trees so the aesthetics of my substrate is of zero consequence (I wouldn't advise perlite for showing a tree of course, but for growing it's great stuff!)

Thanks for sharing your helpful experience, @SU2 , I will consider using it in a mix with relatively high proportion of organics.

 

[Mitty]

I know you wish to keep on the organic trail ; however Perlite and Pumice are both from volcanic sources. I have found Perlite to be very difficult to manage as it floats up to the top when watering. I have just started using a good Lava Rock and that is also from volcanic sources. Now , this really does retain water. You can pound the lava with a hammer to produce the right size granules to use. . I feel you would be better off trying Lava rather than worrying too much about Perlite / Pumice. Lava is known to be ideal for keeping Bonsai trees moist, the Japanese use this and I myself find it is ideal for providing moisture. I found the red Lava better than the black , but either should really help to absorb water for your Bonsai trees.

 

[Harewood Hobbyist]

I am extremely new to small potted trees but

If it is a deeper pot where I am afraid of over watering it, I use half perlite and half diotomaceous gravel. It sets up, holds its shape and doesn't float away under the sprinkler.

I have a lot of miscellaneous plants in very shallow pots, 3 cm at most. For these I do not use any perlite as it will float away.

 

[Clicio]

I know you wish to keep on the organic trail ; however Perlite and Pumice are both from volcanic sources. I have found Perlite to be very difficult to manage as it floats up to the top when watering. I have just started using a good Lava Rock and that is also from volcanic sources. Now , this really does retain water. You can pound the lava with a hammer to produce the right size granules to use. . I feel you would be better off trying Lava rather than worrying too much about Perlite / Pumice. Lava is known to be ideal for keeping Bonsai trees moist, the Japanese use this and I myself find it is ideal for providing moisture. I found the red Lava better than the black , but either should really help to absorb water for your Bonsai trees.

Well, perlite and lava are way different, as pumice and lava are different between them.
Yes, perlite floats.
Yes, I've been using it in a mix that also has lava rock. And I mix perlite with peat, and after layering down the soil I cover the surface with lava, which keeps the floating perlite under control.
We can't get horticultural pumice in Brazil, but I guess it floats also, no?
Thanks for commenting.