Sounds like it will make a fine container. Your soil mix is probably much more water retentive compared to the small surface area of the lava rock. Please post a pic when you have it planted with something.

I agree with Brad, and I've done your idea, Penny, but it was too much work. I now just grow in random piles of rock, but I'm considering building a cairn this year and plugging it with Semps and Sedums. I have a good supply of rockage, but what's in short supply is young back.

MY young back needs a forklift.

Love that this topic has just come up - I've just started to work on rock cairn-like structures to grow a cliff-dwelling cactus (Cleistocactus colademononsis). My goal is that the stems will drape down the cairn similar to how they would do so in the wild...I'll let you know how it turns out!

I have no clue why my husband did this out of the clear blue sky. I guess he's sort of "helping" me with my hobby. Today he found a bunch of pots for me in the garage. I'll take photos of the rock after he finishes drilling the small hole. Then I'll plant a Sempervium in it I think. It should work fine.

Penny

{{gwi:3244}}

Al

Al is my hero. Really cool work there bud!!!

I have many Sempervium planted in lava rocks. Some plantings are over ten years old. I replace a few every once in a while after they bloom and die, but they usually fill in again on their own. I never took the time or effort to drill holes, just placed a little soil in a natural hole and then started a plant in it. I have rarely had any die, so your Sempervium should do very well. I will post pictures tonight when I have time to find them. Good luck, I am sure they will work beautifully.