This group of Needle junipers on a large rock by Norboru Kaneko won first prize at Sakufu-ten #12. It originally appeared in Bonsai Today issue 24 (long out of print). It also appears in our Bonsai Today Masters’ Series Juniper book (still in print).
Root-on-rock vs root-over-rock
The bonsai shown in this post are all root-on-rock, which means that the roots are growing in soil that is in pockets in the rock. Root-over-rock is where the rock sits in soil in a pot and the roots are trained to grow down over the rock and into the soil. We’ll do a post on these later.
Here’s another Needle juniper (with an azalea and some others) by Noboru Kaneko. Also from Bonsai Today 24 and our Juniper book.
And one more. Same artist, same place.
Root-over-rock. Here’s a somewhat fuzzy example of root-over-rock (as contrasted with the root-on-rocks above), that comes from Noelanders Throphy XI – A Film by Merlin. You can see one root (with the white stripe) than snakes down the side of the rock. It’s actually functioning as trunk now; roots that are exposed to air will grow bark and become part of the trunk. This only works if the tips of the root are in soil. If the whole root, including the tips, is exposed to air for more than a few minutes, tips and all will begin to die.