On March 26, 2019, at the Luther Burbank Art and Garden Center, Santa Rosa, California, Randall Lee conducted a demonstration working with Shimpaku juniper. Randall began his demonstration by identifying the various types of junipers used for bonsai. These included Shimpaku, Kishu Shimpaku, Itoigawa Shimpaku, San Jose, Prostrata, Procumbens nana, Buffalo. Sources for purchasing these junipers are bonsai growers and vendors, local nurseries and Home Depot.
Randall described the soil mix he uses as 1/3 Akadama, 1/3 pumice and 1/3 lava rock. He will use a wetter soil mix, 40% pumice and 60% Akadama, as well.
He said organic fertilizer for slower growth. However, since he is using young plants and may want to have more growth, he will use chemical fertilizers, such as Apex, Power Gro, Romeo water soluble fertilizer. He does not use fertilizer cakes and tea bags filled with fertilizer due to rodents being attracted to them.
Randall began working with the Shimpaku demo tree by examining and evaluating the inside of the plant. He could observe many small branches at or near the base of the plant. Some larger branches appeared towards the top portion of the plant. He cut and removed the large, unwanted branches first. His design would be a small bonsai or Shohin classification. He paid close attention to the base of the plant and followed the trunk line from the base of the plant to the apex. He selected a potential front view of the bonsai.
In removing the unwanted branches, he created jins or deadwood features in the bonsai design. Upon removing the largest branches, the Shimpaku juniper began to take shape, thicker at the base and thin towards the top or apex.
Randall emphasized cutting back on the foliage. He removed more than one third of the plant’s foliage at this point. By cutting back on the foliage, he would have the plant back bud on the interior. He said this was important since the Shohin style or small bonsai design required small branches close in to the trunk.
Randall began to place aluminum wire on the small branches. The wire was used to create movement and interest in the setting of the branches. Some branches were too soft and young to wire at this time, but would need wiring when they harden off more. He described the selection of branches to remain on the plant must be in proportion to the trunk of the bonsai.
Care for the Shimpaku juniper post demonstration included keeping it out of the direct sun for few weeks. “Let it grow and relax” according to Randall. He removed a lot of foliage and the plant needed to rest for a while. He would not fertilize for four to six weeks.
Upon completion of the demonstration, a raffle for the newly created bonsai was held. REBS member Diane Matzen purchased the winning raffle ticket for the Shimpaku juniper.