A good nebari (exposed roots just above the soil surface) and a large trunk base are perhaps the two most desirable features we all wanted for our bonsai. However, they take a long time to develop. Many of us buy pre-bonsai. At the nursery, we may dig below the soil level, hold the tree up, turn it around and tilt it at various angles to choose the best possible material but it is rare to find one with both a good nebari and a large trunk.
In this post, I want to share my experience building a good nebari, at least to my eyes, and a large tapered trunk for a Ficus microcarpa pre-bonsai. I bought this ficus about 9 years ago from a gift shop of a local Chinese restaurant. As in all mass-produced pre-bonsai, they usually have messy or unattractive roots and a typical S-shape trunk. What attracted me to this tree was the large trunk base, however, it has a nagging thick root, about 2″ diameter, growing on the convex side of the trunk’s first curve, and plunging down into the soil like a large inverted J-hook. Nevertheless it was a good starting material.
When we begin to train our tree with a faulty root such as this one, uneven trunk movement or branch placement, it is imperative that we correct them as early as possible. If not, they will stay with the tree and may beome more troublesome to correct at a later date. We have to decide how we want our bonsai to look like in 5, 10 or more years down the line. There is no short cut unless you want to spend big bucks buying a “specimen” tree from bonsai professionals.
This is how this ficus looked in July this year after defoliation and wiring. The root spread is about 10″ at the soil level and the trunk diameter is about 4½” above the root base.
I do not have a photo of this pre-bonsai ficus when I bought it. The 2007’s first repotting photo gives an idea of how it looked after removing the ugly high up thick roots and cutting back all the excessively thick and unwanted roots.
Below are the 2007, 2010 and 2016 side-by-side photos showing where the cuts were made, where aerial and adventitious roots were used to fill the gaps and to create the nebari, and where the apex was allowed to grow freely, chopped, grow a new leader again to create the taper.
The above composite photo is pretty much self explanatory. I will add a few notes:
A – where the ~2″ diameter large protruded side root was removed, wound callused with the help of aerial roots.
B – this root was bent sideways so that it does not project straight out to the viewing front.
C – as the ficus root thickened, it also bulged up like a knee; the bulge was removed and finally healed to give a smoother transition.
D – branch near inner curve was removed.
E – leader was allowed to grow and thicken, then chopped back; a new leader was allowed to grow freely to develop good taper at the top.
F – I should have removed this back branch and allowed the frontal small one to grow. Now the back branch has grown too thick for a branch located at this height, I can now go ahead and remove it, just leaving a larger wound to heal.
As I grow the nebari and a fat trunk base, like the proverbial saying: “As we grow older, we loose our shapely curves”. With a well spread rootage, a fat trunk base and taper, this ficus looks very stable. Now I have to work on the branches and their ramifications.
A few more notes about the first repotting and root corrections:
I wired and spread the roots outwards.
I also sealed the large basal wounds with Top Jin cut-paste which contains antifugal chemical to prevent them from rotting since those wounds were below soil level.
Last but not least, fertilize, fertilize and fertilize! I just use cheap composted chicken manure as my main fertilizer, $7 for a 40 lb. bag. People were surprised and always ask isn’t chicken fertilizer too hot for the tree? Well, it is composted and I have yet to have my trees burnt. The other good reason is squirrels do not like chicken manure. I once bought an 18 lb. tin can of imported organic fertilizer; the ferilizer balls were all stolen by squirrels. I also supplemented with foliar feeding of seaweed emulsion and humic acid.