Yes, I found the info on line, so figured why not try it
Went to the produce section of the grocery store and bought a $3 container of water cress ... it was just the greens, no roots, etc ... threw the sprigs into a bowl of water. I didnt follow the directions very well ... the site said to change the water daily, or the water would go green ... yup, green slimy water, and some of the sprigs wilted/rotted and smelled really bad ... but after maybe 5 days, they did have nice little roots started ...
I ended up with maybe 8-10 healthy rooted sprigs, put them all in one pot ...
Then threw the pot into a wet area to harden the plant off ... again, poor care ... didnt put it in a sheltered area, just right out into full summer sun, exposed to wind, etc ... it fried a little, but then bounced back.
The plant growing on the left side of the waterfall is the same plant... picture taken in Sept. It was VERY happy to get planted at the waterfall and started to spread.
These are pictures taken this morning ... the first picture shows one of the guilty fish who was eating it til they spotted me. Just for size comparision, this butterfly is 18-20 inches (no more than 20") ...
This picture is just to show the floating roots that WERE under the rock til a certain few started tearing the plant apart LOL,,,
taken from a different angle, you can see the lighter green, new growth trying to get going (if the fish would stop eating it LOL)
I keep meaning to grab another container of water cress sprigs from the grocery store, to start a few more plants. I want to get some growing on the right side of that waterfall, and more or less cover the rock wall under the marigolds ... it seems to grow the same way as creeping phlox ... any crevice in the rocks is fair game for the roots to take hold. A nice bonus here (zone 6) is it stayed green through the end of December, and even when it was totally encrusted in ice, it didnt die completely, just went a really dark green, almost purple. Here's a picture taken Dec 30th. Not the best, but you can make out some ice on it ...