Repotting the California Juniper #418
By George Haas
On September 29, 2024, at the Bonsai Garden at Lake Merritt, Oakland, California, a special team was assembled to take on the task of repotting a giant California juniper (Juniperus californica), estimated to be over 1,000 years old.
The team leaders were Peter Tea, a notable bonsai professional, and Bill Castellon, a well-known Japanese landscape contractor.
The subject bonsai is #418, California juniper, 58 inches in height, 36 inches in diameter, informal upright style. “Yamadori” means in Japanese “collected from the wild.” This tree was collected sometime in 1980s by Ray Thieme and Richard Ramirez of the Fresno Bonsai Club. Presumably, Harry Hirao escorted them in search of the bonsai material at Jawbone Canyon in the Mojave Desert, located in southern California. It was then six feet tall with a 36-inch diameter trunk. Once collected, it was placed in a 48 by 48-inch wooden box to recover from the digging.
The tree was initially styled by Harry Hirao and Jack Sustic at the 2003 Golden State Bonsai Federation (GSBF) Convention in Fresno, California. Styling took four men most of the two-day event, and still required many more hours of detailed wiring. The demonstration tree was displayed at the convention next to its future pot, a 48 by 35-inch rectangle clay container. The large pot was purchased by the GSBF Fresno convention.
The impressive California juniper bonsai was donated to the Bonsai Garden at Lake Merritt by Ray Thieme in 2004. The tree is located outside the bonsai garden’s perimeter fence, next to a large limestone boulder or Chinese Gongshi (also known as scholar’s rock). The giant bonsai beckons visitors to the bonsai garden.
All bonsai require re-potting from time to time. A general rule for a large bonsai tree would be five to seven years due to the following factors:
- Age of the tree
- Size of the tree and pot
- Breakdown of the soil or compacted soil
- Root growth or root bound
- Water flow decreases
The last time this California juniper was re-potted was 16 years ago.
Peter Tea was requested to repot the California juniper. The task would require the assistance from his apprentice Travis Hendrix, clients and helpers Bob Ricker and Tony Henninger, and volunteer Michal Tiede.
Bill Castellon brought a metal tripod for lifting the giant tree and root ball from the pot.
The wooden flatform required repairs by placing new boards to support the weight of the tree and pot.
The tripod was positioned directly over the tree and pot. Then, a large amount of soil was removed from around the root ball and container in order to free up the tree and make it easier to lift the tree and root ball from the container.
Peter described the overall health of the tree as good though he expected more root growth considering the tree was in the pot for 15 years or so. When removing the soil to get the tree out of the pot, he did notice that the soil was very wet. He used a thick layer of pumice on the bottom of the pot to keep it a bit dryer. The soil mix for the rest was large 33% Akadama, 66% pumice. As he moved to the topsoil, a smaller soil was of the same mix percentages. He also added starter fertilizer on different levels of the soil to help the roots recover from the repot. Peter would recommend using some sort of spray irrigation instead of the soaker hoses because the soil is now so porous that they may not give enough coverage of the soil. Also, the core of the tree was fairly dry so getting water closer to the center would be helpful, especially since the center is where all the roots are now.
1 Tripod positioned directly over the juniper
2 Work begins to remove soil from root ball and container
3 Removing soil to free up the juniper and root ball
4 The tripod and hoist made it easy to lift the tree and root ball from the container
5 The juniper is freed and wheeled into the garden’s workshop area where work would take place
6 Work on repairing the wooden platform is undertaken by garden handyman Fabian
7 The pot is cleaned thoroughly and drain holes are screened off
8 Tie down wires are inserted in the holes through the bottom of the pot
9 Soil mixes are put through a sieve to remove fines
10 Steps are taken to replace the large pot on the newly repaired wooden platform
11 The juniper is again lifted and returned to its pot
12 The tripod is removed and work on replacing soil begins
13 Soil is replaced using a measured amount of sieved pumice and Akadama
14 The work of adding soil mix is crucial and overseen by Peter Tea
15 After a thorough watering, (L to R) Travis Hendrix, Peter Tea, Bob Ricker, and Tony Henninger pose for a photograph and job well done!
16 Bill Castellon gives a thumbs up to the completed task!
17 Thanks to Yuri Aono the automatic drip irrigation hoses are hooked up to water the juniper
California Coast Redwood
Gary Tom and his assistant Lucky Fung making a tree healthy and beautiful
Gary Tom and his helper Emma Interi making a tree healthy and beautiful (2017)