Are you talking about growing in very large lava rock/s?

I use small lava rock (Scoria) as a planting medium all the time. In fact, my Pachira
is in a mix of lava rock, perlite, and bark. There might be some pumice, too.

You need to make sure that moisture and nutrients are provided.

Josh

Thanks Josh! Yes I meant very large lava rock though. Take a look at the link.

Here is a link that might be useful: {{gwi:106220}}

the plant in the picture was rooted in a depression in the rock. The rock was partially submerged in a weak nutrient solution with the rock wicking sufficient water & nutrients to keep the plant happy, or grown under very high humidity with the rock being spritzed regularly with water & nutrient solution. Either method provides a favorable environment for the development of healthy roots - requisite for healthy plants.

This planting is similar, though there is a very small amount of soil in the very small depressions in the rock:
{{gwi:3244}}.

It gets watered with a contact lens solution bottle filled with distilled water or nutrient solution, depending on the plant's needs.

Al

Al, that looks amazing! Did you grow that yourself? Oh no! I feel a new obsession coming on!

Yes, I planted it & maintained it until it outgrew the rock after 2-3 years. It's a piece of lava my brother brought back from Hawaii. There are several succulents, Carissa, and Hedera (ivy) all mixed in on the same rock, and many are plants you wouldn't normally find growing side by side ..... 7 or 8 different plants if you look closely.

Al

That is the coolest thing I've seem! How'd you attach them at first?

Some are in tiny pockets of soil & others are simply stuck into very small holes in the rock. I put the whole planting in a 10 gallon aquarium I often use as a propagation chamber, with a glass cover and a double 24" bulb fluorescent fixture for light. The aquarium was slightly vented so humidity was high but there was still some air flow, & I misted only the rock daily or twice daily until roots had grown into the rock pores to the extent they would support the plants.

Al

{{gwi:3266}}

{{gwi:13099}}

Joe, glad you broahed this subject. In 2010, I got an Anthurium but it's growing in wood, not lava rock. I don't know its proper care.

The instructions said to mist, but I wonder if spraying is enough moisture. No mention fertilizing.
Or, what to do when roots take over.

Here's an older pic of mine..it needs work.

{{gwi:106222}}

Hope you get an answer on care, etc. Toni

Al, I am beyond impressed with your work! So thoughtful, creative and just cool! Toni, I wish I could help lol. I'm clueless with these anthurium Plantings!

{{gwi:3243}}

The next two are the same plant, a snapdragon before & after pruning. Thanks for the kind words, btw. Plants that don't lend themselves to being instilled with a personality just don't interest me much. In order for me to want to grow something in a pot, it has to be something I can manipulate into something attractive or unusual.
{{gwi:3254}}
{{gwi:3253}}

Take care.

Al

Al, would should compare notes! I love your style! I actually did my best at starting a schefflera and a anthurium in lava. Going to take pictures right now and post them in another followup here.