This is a great time of year to go hunting at local garden centers and home improvement stores for nursery stock trees that will make incredible bonsai for your collection for only a small financial investment. We have been discussing this some on the RMBS members forum, and a recent blog post on RMBonsai.org outlines my method for selecting this material (huge thanks are due here to Ryan Neil of International Bonsai Mirai for the knowledge).
Nursery Stock Sabina Juniper Part One: Root work and potting
I happened to be at a large orange-colored box store this weekend to get some gravel for my garden and just couldn’t stop myself from picking through the stock of medium sized junipers there for sale. I happened upon a tree that was suitable, and the price was right. $25 all in. If nothing else, stock junipers are great to get “some turns” for wiring practice and make very attractive trees, even in small size.
I have never worked with juniperus sabina before, but I think that the common juniper bonsai techniques will apply. I have seen some Sabina juniper bonsai from Europe that are very desirable specimens.

Typical nursery tag with very little usable horticultural information.
I chose this tree because it had a single trunk (not a clump) and the trunk made two very distinctive movements that added interest, and an overall style that lends itself to a semi or full cascade (which I have very few of in my garden). Beyond this, there is very little to recommend this tree or distinguish it from the 30 others I reviewed on the shelf. It will make a good bonsai, not an exceptional one. All told, I will likely have a tree worth a couple hundred dollars from an investment of about one tenth of that.

Looks like every other bush on the rack at the box store.

At least the trunk has a bit of interesting movement. Not much else to recommend this stock.
Step one: Assemble tools and usable workspace. Knock it out of the nursery can and start reducing the soil mass with a chopstick. As will most nursery stock, this tree was completely pot-bound, with numerous large roots encircling the can. This tends to be easy work, and you should work starting at the top and pull radially from the trunk toward the outer ring of the root mass. You should start from the top and work down to identify the true nebari (basal root flare). You will need to remove diminutive roots that emanate from the trunk above the larger basal root flare: this is easily accomplished with scissors. As with many stock juniper, the nebari on this tree was not readily apparent, but I was able to get to some large roots all emerging from about the same area. This was about 1/3 or a bit more down into the nursery can.
Step two: Once you feel you have identified the true basal root flare, start working the bottom and sides down to a reasonable mass with the same inside-to-outside chopstick technique and removing unwanted roots with a scissor, assuring sharp clean cuts. It was helpful to have identified a usable cascade style pot and to dry fit the root mass periodically to see if I had reduced enough. I think all together, I took off about 50% of the existing root mass, focusing on removing long, stringy roots that were coarse and without a large mass of fine feeder roots.

Root mass after working, prior to potting. Lots of fine roots remain. Basal flare identified.
Step 3: Prepare the pot with drainage screen and tie down wires. This pot posed a problem (which is a common one) with only a single drainage hole at the bottom and no other areas to string tie wires. I will omit the primer on proper potting here but show you how I tied this tree down using a bar of heavy gauge copper wire, clipped to length and stainless-steel tie-down wire (will not stretch). I inserted a chopstick into the root mass above as an anchor to tie half the tree down (again, a topic for another message).

A common tie-down wire problem: remedied.
Step 4: I potted the tree with a layer of coarse aeration soil at the base (same composition as the rest of the soil, just a fraction larger). I tied the tree down loosely, then filled the pot with soil. Pushing the soil first in around the tree with my fingers to “bulk-fill” the spaces. Then I tightened the tie-downs snug once I had the tree at the angle which I thought was suitable for the next 2-5 years of training. After this, I filled the pot with more soil and chopsticked in the rest of the soil to eliminate all of the empty space in the container. I top-dressed the surface with mountain moss (to keep the soil from