I love the idea of a rock/water wall.
>From the plants I grow maybe I can offer you a few suggestions.
I think you could use many of the epiphytic
ferns. Some that would 'work' well would be species of Microgramma,
Asplenium, Elaphoglossum, Davallia, Pyrrosia, Microsorum, Polypodium, etc.
There are several species of Microgramma that sty miniature in size and will
develop into an attractive blanket of tiny fronds.
You might want to consider other ferns too, like
Pteris, Adiantum, Blechnum, Microlepia, but beware of Nephrolepis.
Nepholepis tends to become a weed and will either
over spore on to your rock surfaces or send out it's thin stolons that produce
tubers and will become next to impossible to remove once the
tubers grow in between the rock crevasses.
Selaginella loves moist rocks and there are several
species offering different looks, colors and growing patterns.
Lycopodium, the epiphytic types of club moss, would
also do nicely.
If you want aroids, the Homalomena love water and
some species stay low growing. Cyrtosperma enjoy being wet too, and
so do the Spathiphyllum. The species Spathiphyllum florabundum stay small
You might want to try something like Rhipsalis
too. Small cuttings could be tucked into the spaces between the rocks and
it will grow nicely, being epiphytic and would look good being
Rhizomatous Begonias do really well growing around
moist rocks, and they offer some beautiful foliage color and patterns as well as
tall flower spikes. Some are also miniature, or small growing so
they won't crowd out other plants.
Re: Carnivorous plants, could a Nepenthes be
used? Although I grow Nepenthes mostly in hanging baskets I know in
nature they ramble on the ground around rocks and such. I recently planted
one to grow around some Volcanic rocks outlining a planting area and it seems
happy growing and creeping around.
I hope some of these plants will give you more
ideas for your wall, and when it is complete you will share some images
PS If you need species names
or pictures, just drop me a note.