I love that tiny treasure of a garden, David!
Chelle, I found a pic of the nursery's deep gravel bed. The plants aren't watered or fed. The plants grow how they would in nature, I guess!
The nurseryman told me that when planting in gravel the one thing you must not do is to leave peat-based potting soil on the plant's roots. The peat dries out and the plant shrivels before it has a chance to root into the gravel. If the plant is grown in a soil-based mix, however, it will establish itself in gravel easily.
