Similar but different enough I figure everyone has their reasons for choosing one over another.

Curious what you prefer and why.

I tend to use pumice. It's cheap, and helps me regulate drainage and water retention.

I've read Vermiculite can help add nutrients to the soil over time and should probably try it again.

As far as I know both Vermiculite and perlite require a lot of heat during manufacturing, so pumice (while not perfect, still needs to be gathered somewhere) seems to have a smaller eco-footprint.

My apologies if this has been discussed before.

It depends upon what you are trying to accomplish. Vermiculite adds water retentiveness but perlite and pumice add air spaces so both aid in drying.

I find vermiculite to be fairly fragile and ends up being really tiny pieces that act like glue. Great for water and nutrient retention, bad for drainage and air space. Mixed with perlite makes a good seed and cutting mix. Toss in a little sand for 'tooth' and substance.
Perlite is great for opening potting soils up and allowing air in. So lightweight that a lot of it ends up on top and not helpful, though. Kind of brittle like vermiculite but still more substantial.
Pumice is like heavy, sturdy perlite. Most of it stays in the soil mass doing its job. Much less "artificial" blinding white like perlite, too. Gets stained by organics in the mix fairly quickly to blend in and look more "normal" than perlite. Yes, much more eco-friendly than either of the other two.

My preference has always been pumice since it is heavier than perlite. Oftentimes perlite tends to float especially if other soil materials are heavier and then gets soaked, perlite ends up floating upwards and then washed away. Pumice also helps hold down top heavy plants better. In some areas pumice is not readily available so it becomes a costlier alternative to perlite. Thankfully I can easily get this here in NorCal.

I don't use vermiculite since it is more water retentive. My plants are mainly succulents and drought tolerant plants that needs faster drainage and good airflow at rootzone so pumice is my first choice to add in my media mix. Even if I already use cacti mix, I still add a bit more pumice since most of my plants stays outdoors during winter..and winter is our rainy period, so I have to make sure media drains fast enough and continue helping roots get air at the rootzone especially when soil gets soggy from being wet after it rains.

CPPgardener said: Gets stained by organics in the mix fairly quickly to blend in and look more "normal" than perlite.

Yeah!

I've had monstera cuttings and aloe brevifolia with heavy pumice, and now that you mention it it does take on color very quickly.

Do you think that's good or bad, and why?

I''m guessing, but if it can act as a nutrient sink that could be beneficial.

If it becomes another rotting nutrient source, I assume that'd be bad.

CPPgardener said:
Gets stained by organics in the mix fairly quickly to blend in and look more "normal" than perlite. Yes, much more eco-friendly than either of the other two.

Thanks.

It's not just me. Good to know.

I would not use vermiculite in a "permanent" planting at all because it collapses when wet.

Vermiculite is useful for starting herbaceous cuttings. But I agree with above opinions, def not good for potting soil drainage. I'm often confused about why your opening sentiment is so often expressed: "Similar but different enough I figure everyone has their reasons for choosing one over another." Vermiculite is similar to perlite only in that it is a heat-treated mineral, otherwise it has completely opposite qualities. I don't like the floaty dusty nature of perlite and prefer pumice in potting soil, although it is kinda heavy in larger pots.

After reading this thread I bought some pumice because some of my plants are not draining quickly enough. For repotting what percentage do you use?

It depends upon what plant you are repotting and what potting soil you are using.

Humboldt, the staining is from soluble organic humid acids and won't add the decomposable matter. Possibly a VERY slow source of nutrients.

NMoasis said:I'm often confused about why your opening sentiment is so often expressed: "Similar but different enough I figure everyone has their reasons for choosing one over another." Vermiculite is similar to perlite only in that it is a heat-treated mineral, otherwise it has completely opposite qualities. I don't like the floaty dusty nature of perlite and prefer pumice in potting soil, although it is kinda heavy in larger pots.

Thanks for your response. Agreed, when I water anything with perlite it's by hand to avoid washing it out.

I figure larger pots are going to throw my back out anyway, don't think it's the pumice.

By similar I just meant appearance...small, white, puffy.

Different as in in "completely opposite qualities" like you said.

I see them recommended and used in similar ways that don't always make sense, just wanted other opinions.

DaisyI said:It depends upon what plant you are repotting and what potting soil you are using.

Yep.

Also depends what you're adding it to.

Succulents I go heavy, same for cuttings.

Non-succulents, would depend on the plant.

CPPgardener said:Humboldt, the staining is from soluble organic humid acids and won't add the decomposable matter. Possibly a VERY slow source of nutrients.

Good to know, thanks!

But why does pumice seem to discolor faster than perlite or vermiculite?

IDK but if perlite was a darker color, I wouldn't be so repulsed by it.

Humboldt said: ... By similar I just meant appearance...small, white, puffy. ...

Not to belabor the point, but are we talking about the same thing? Here are the perlite and vermiculite products that I have


I know vermiculite is also available in a coarser texture, but I think it's basically the same color.

Humboldt said: I see them recommended and used in similar ways that don't always make sense, just wanted other opinions.

That's where I'm confused, too. I also see recommendations implying they can be used interchangeably. Am I missing something?

Those writing about interchangeability are the parrot-type writers, repeating what they've heard, not actual gardeners sharing experiences. It's hard for new gardeners, and sometimes old gardeners, to tell the difference. There are so many parrot-type plant websites. An all-too-common clue is when they are talking about one plant but have a pic of another plant. I see that often.

Those working with vermiculite should investigate the potential hazards of the dust.
https://www.epa.gov/asbestos/i...

NMoasis said:

Not to belabor the point, but are we talking about the same thing? Here are the perlite and vermiculite products that I have


I know vermiculite is also available in a coarser texture, but I think it's basically the same color.

Very dramatic difference, given.

I've seen much lighter vermiculite https://www.google.com/search?... but it has been a while since I've purchased it.

purpleinopp said:

Those working with vermiculite should investigate the potential hazards of the dust.
https://www.epa.gov/asbestos/i...

Good call, same for sharp sand.