This article is reproduced from the American Bonsai Society Journal;  Volume 44; No. 1 (Winter 2010) under author reproduction rights.  Note that this is a more complete version.  The magazine published article contained only seven photos. Additional photos and text comments are added to this Fuku-Bonsai website article to provide additional insights. ~~~DWF
REFINING MATURE DWARF
SCHEFFLERA BONSAI
By David W. Fukumoto (Kurtistown, Hawaii)
From left, Ron Davis of Montana and Phil Bill from California as they begin work on this Dwarf Schefflera bonsai.

        Training and refining tropical bonsai can be reduced to a set of principles. Each tree should celebrate the unique horticultural traits common to the specie. Dwarf Schefflera, Schefflera arboricola, has extraordinary banyan traits so the challenge is to feature aerial roots!  The top photo shows the tree after several years of rampant growth in a very shady location next to thick shrubs.  That very high humidity situation produced an abundance of very desirable aerial roots that fell dramatically from branches.

 

 

 

 

 

 

        The class was scheduled for planned visits by Phil Bill of California and Ron Davis of Montana.  Both had visited several times previously and had taken various workshop classes. First remove all leaves and locate and mark the overall apical point. Second, locate and mark the ends of the lower branches.  With thin sticks, connect the points, then prune off all growth above the points. A lot takes place before Ron snips off the apical growth to complete the transformation a few days later! This article gives an insight into refinement principles that upgrade good quality bonsai into masterpiece bonsai!
CONTROLLED RAMPANT GROWTH

       Rampant growth is a valuable development strategy and technique. Skilled bonsai trainers can immediately sense the growth rate of any bonsai and can control the growth rate to achieve objectives.  Some hobbyists are so focused on reducing leaf size that their plants become stunted and trunks and branches stop developing. What good are small leaves on thin, spindly trunks? Others want optimum healthy growth and wonder why they cannot create fine detailed twig ramification. The ability to control grow is essential.

      A period of rampant growth is needed to rejuvenate bonsai that have been stunted by being pot-bound, due to excessive leaf or twig pruning, or after a prolonged period of being insufficiently fertilized. Repotting or planting in the ground will rejuvenate the tree, produce more vigorous growth, and help thicken trunks and branches.
        The Chinese often begin training by collecting a tree from the wild, reducing it to a compact root system with just a few inches of trunk and allowing it to sprout all over. While in the ground, new apical growth is selected and allowed to grow vigorously until the base of the new growth is half the size of the reduction cut.  It is then reduced, branches selected and shortened, and allowed another period of rampant growth. After several months or years,  the plant is dug up, potted, and the best trunk and branch framework is selected. This development strategy would be less effective with slower growth in the pots.
        In the case of this Dwarf Schefflera, rampant growth was desirable to thicken existing roots and to develop new fee-falling aerial roots dropping from branches far from the main trunk.  This was a greater challenge as the branches of the rock planting were extra high and creating free falling aerial roots was significantly more difficult. To achieve the desired results, a shady, high humidity location was selected in which light would only reach the plant from one side. Over five or six years, aerial roots developed in the shadiest areas. They were carefully guided down until they contacted the ground, got established, and naturally pulled taut. 
        (Fuku-Bonsai's senior plant manager assisted in repotting.  The tall rock weighs over 70 pounds.  It was mounted onto a concrete base that holds it upright in the pot.  In the many years since the plant was repotted, a lot of roots have gone under the concrete base. In the photo below,  Ron and Phil complete the root pruning, then repotting.  After the start of cleaning up the root patterns by pruning, the workshop for the day ended.)
        (Handling aerial roots is initially difficult as in the beginning,  many want to preserve and save every root!  But, if you're able to develop a lot of aeral roots and preserve everyone,  you'll end up with a lot of small roots that cross each other giving a very messy appearance.  So I try for fewer roots that are allowed to stay exposed and grow heavier and in a more orderly manner.  Note in the photo taken after repotting was completed that aluminum foil columns filled with media allowed the aerial roots to reach the ground.)
       "RAINFOREST BANYAN" styling is the most difficult of all banyan bonsai styles!  Aerial roots drop from branches straight down to the ground and far from the trunk.  This will only happen in humid rain forests as the roots will shrivel and never reach the ground in dry areas.  In this very rare bonsai,  aerial roots drop from almost the apical growth and the longest aerial root is 33" long!  The total height of the tree from the pot rim is 40"!
 
 
RAINFOREST BANYAN ROCK PLANTING
REFINEMENT PRINCIPLES

            Use wire to spread or to pull roots together so each is as vertical as possible.

           Aim for "visual simplicity."  Rampant growth produces a large amount of branch and foliage growth that can be removed and a proportionately large amount of roots can also be safely removed.  I generally favor retaining older, thicker roots and removing most of the younger thinner roots. Remove crossing roots and those that cross over the surface of the rocks to allow the rocks to be seen.

       While the principles are simple, the work is time consuming and detailed. Refinement includes repotting and placing the tree into an environment with more even light. 

 

 

        Ron was involved in the entire two-day workshop and was able to be exposed to concepts and practices still being developed at Fuku-Bonsai.  With a different bonsai background, he saw things from a different perspective and we learned, too!  We leave the main central apical growth on until the very end so we are aware of the high point of the crown while working on the tree. So our guest Ron Davis had the honor of snipping off the last apical growth to end the workshop!

                    Within a few months, the bonsai has leafed out.  This tree is displayed mounted on a turn-table so visitors can appreciate it form all sides.  The rock planting was made in 1975 when two multiple trunked trees (that were already 3 years in training) were rock planted.  It is 40" tall overall with the width of the foliage crown about 55" across.  The fiberglass pot is 34" in diameter and 3 1/2" high.

                   (NOTE:  Dwarf Schefflera (Schefflera arboricola) is endemic in a range of variations from southeast Asia.  Like plants in the Ficus family, they are lumped together under a common botanical name but observant bonsai specialists recognize major variations. There are two distinctive forms. One form tends to have smaller more disciplined leaves but tends to have less vigorous growth and fewer aerial roots.  The other form has larger leaves, more robust growth, and more aerial roots. 

                    In Hawaii, certified export nurseries were being discussed in the late 1960's as a possible new industry for the state.  With a tropical climate, the proposed industry would specialize in tropical houseplants.  Fuku-Bonsai founder David Fukumoto participated in developing the protocol that formed the Hawaii State Certified Nurseries. When California approved it, the Fukumotos moved to the Big Island of Hawaii to form Fuku-Bonsai as Hawaii's first certified nursery. Hawaii introduced Dwarf Schefflera nationally and in the trade the plant is known as the "HAWAIIAN UMBRELLA TREE."  The bonsai featured in this article is amongst the oldest known Dwarf Schefflera bonsai.

You are cordially invited to visit:
FUKU-BONSAI CULTURAL CENTER &
HAWAII STATE BONSAI REPOSITORY
          PO Box 6000 (17-856 Olaa Road), Kurtistown, Hawaii 96760
          Phone (808) 982-9880;  Email:  sales@fukubonsai.com;  URL:  www.fukubonsai.com

 

                                          American Bonsai Society and Fuku-Bonsai, 2010-2011