Bay Area Satsuki Aikokai

Satsuki Azalea Bonsai Club

Category: Uncategorized (Page 1 of 2)

BASA Annual Satsuki Bonsai Show

Repotting Guidelines for Satsuki Azaleas

The following instructions have been provided by Darren Wong to insure our satsuki azaleas are repotted properly for health and vigor throughout the year:

• Start in February.  Begin with the “narrow leaf” varieties first.  In March continue with all other varieties.

• Kanuma size is important;  use 100% small size for shohin, for larger trees use a 50/50 mix of medium and small.  The larger the azalea, the less small size you use.

• In general remove approximately 50% of root ball and 1″ from sides. Typically work down 3/4 to 1 inch on the surface. Sides should be flat with slightly brushed edges so that a very, very small root end is exposed.

• Be extremely careful in combing out surface roots. If you use a rake turn it so the tines are parallel to the roots to prevent tearing. A better solution is a fine root hook or chopstick.

• Use large drainage mesh on bottom of pot for everything except shohin. This helps water drain better in the pot.

• Use a layer of larger kanuma on bottom of pot for trees larger than shohin.

• Create a cone of soil in the center of the pot so that the tree can be ‘screwed’ into the soil to reduce air pockets under the tree.

• If repotting a bare-rooted tree, or one with open space on the bottom of the tree, be sure to all all holes with kanuma. Leave no air pockets which will result in dead roots = dead branches = dead trees.

Editor’s note: Jonas Dupuich just posted an excellent article on repotting satsuki where he recommends turning the tree upside down, filling all holes between roots with kanuma and working it in gently with a chopstick, then moistening the soil to keep it in place when the tree is turned upside down to go into the pot.

• After tying tree into the pot add kanuma slowly and work into the roots as you go, leaving no voids around the roots, but do not over work the chopping-in process which will crush the kanuma and impede proper drainage.

• Fill pot with kanuma once soil has been properly worked into the roots, and top off with a layer of mountain moss – yamagoke.

• After repotting products like Hormex® can be added to provide health to the trees and resupply beneficial bacteria which may have been killed with a prior year treatment of Subdue®.

• Be mindful of watering after repotting and don’t overdo it.

• Keep trees protected from excess wind, cold and ‘Atmospheric Rivers’.

• Wait for at least 30 days to begin fertilization.

Second Editors Note: In a discussion with Peter Tea about the problem many have with root rot he suggested adding some pumice to the kanuma soil mix to create a drier mix which could reduce or eliminate the problem. Darren has not tried this and his take was to add about 20% yamagoke to the kanuma which might accomplish the same goal.

At our February meeting Bob Gould suggest that if the above method is tried with pumice that the drier mix should only be used on the bottom 1/4 or 1/3 of the pot.

24th Annual Satsuki Azalea Bonsai Show

24th Annual Satsuki Azalea Bonsai Show

Recharge – Professional Strength Microbial Superpack

Warning: For your consideration, while bacteria and fungi of this product are beneficial to your plants, the same is not true for you. Those agents can be infectious for humans. They are common and we unknowingly encounter them in our gardening and potting of plants. Practice standard sanitary procedures to protect yourself. This product is dry and a bit dusty, be careful when handling that the dust or the liquid mix does not get in your eyes, nose or mouth, or cuts or sores you may have on your hands or arms. Just use reasonable precautions when using the product. Always read the instructions and caution labels.

Mary purchased a new product which has gained wide use by members of the North American Clivia Society. Clivias, even more than azaleas are subject to root rot, and this seems to be an important step in controlling the problem. It is produced by Real Growers (link below) of Fort Collins, Colorado. That is the home of Colorado State University (the old Colorado A&M), an important research university. I am sure, with Colorado’s legalizing marijuana, that this product was developed for that market. It is called ‘Recharge – Professional Strength Microbial Superpack’. I believe it could be quite useful to California azalea growers as our climate is very favorable to the growth of the various fungi that may cause root rot. Its best use is as a preventative, or after the application of anti-fungal chemicals that often deplete the soil in pots of the good fungi as well as the bad. The product is fairly expensive, the basic containers 8 ounces, 16 ounces and 5 pounds, and is used at the rate of 2.5 grams per gallon of water, applied I noted that the label calls for continuous or frequent use every 7 to 10 days. And I also think that is intended for the commercial growers, probably using flow through watering and fertilizing systems. For our purposes I think use with regular periodic feedings would be very adequate. All we really need is the agents be introduced into our potting soil. They should be self-sustaining and in fact thrive unless there are unusual circumstances such as extreme temperatures or the introduction of fungicides or anti-biotics. One 16 oz. container will make about 160 gallons of solution.

Perhaps we could find a way to split a container among those that might be interested. The contents include spores of six fungi and starting colonies of four bacillus. I’m going to use some of Mary’s on my azaleas, particularly as I repot them, or if any show signs of trouble I’ll keep a record so I can report in the product efficacy from my experience. From the label – “This product is intended to be used as a soil amendment to establish colonies of beneficial bacteria (and fungi) in horticultural systems.” Also available from Amazon, but what isn’t!
– – Don Meeker


Recharge is loaded with mycorrhizae and Trichoderma fungi as well as the strongest microbe package available anywhere. We add organic goodies including kelp, molasses, humic acid, fulvic acid and amino acids to develop a healthy colony of living soil microbes. Undiluted, uncut and delivered at true professional strength concentrations.




Engraved Brick Fundraiser

The Bonsai Garden at Lake Merritt has been raising funds for its Garden Revitalization Project (GRO). This project aims to upgrade the display benches and stands, watering system, pathways, and much more, in order to meet the challenges of caring for and maintaining the historic and legacy bonsai collection in a professional and museum quality manner.
As part of this, they have initiated a recognition brick fundraiser drive in which individuals, clubs and businesses can purchase a variety of state of the art engraved bricks, and the proceeds will go towards the GRO Project. GRO projects include laying cement pavers for all pathways within the Bonsai Garden, and the engraved bricks will line a special pathway.
For information

Example: personal engraved brick

Secrets of Bonsai: Uncovering the mechanism of root regeneration

ReIncreased levels of AUX/IAA19, which indicate an activation of auxin signaling, were observed in the cut-end of root-cut plants compared to intact plants. Scale bar = 0.1 mm. Credit: Xu D. et al., Plant and Cell Physiology, September 1, 2017.

The molecular mechanism behind root regeneration after root cutting in plants has been discovered. A finding which could lead to the development of new methods for regulating plant growth in agriculture and horticulture.

A plant’s root system is highly regenerative. It plays a critical role in absorbing water and nutrients from the soil and therefore its loss can be an immediate threat to their lives. The plasticity of the root system also helps plants adopt to adverse conditions such as draught. An agricultural technique called root pruning, or root cutting, uses this natural robustness to control plant growth. It has also been used in horticulture to control plant size and vigor as seen in Bonsai.

Previous studies have suggested that root regeneration occurs through the induction of lateral root (LR) formation, and that auxin, a well-studied growth hormone involved in various processes of plant development, plays a role in the process. However, the molecular mechanism behind root regeneration has remained largely unknown.

According to a new study published in Plant and Cell Physiology, scientists have identified for the first time that YUCCA9, one of the eleven YUCCA genes involved in auxin synthesis, plays a primary role in root-system regeneration.

Using Arabidopsis as a model, the research team led by Associate Professor Masaaki Watahiki of Hokkaido University found that root cutting induces both LR formation and the growth of existing roots. Experiments investigating gene expressions and using mutants identified YUCCA9 as the primary gene responsible for auxin biosynthesis during root-system regeneration after root cutting. In collaboration with Professor Masashi Asahina of Teikyo University, the team also found an evident increase in the level of auxin after cutting.

Auxin commonly shows an uneven distribution in plant bodies as a result of polar transportation, leading to gravity – or light-induced bending of the plant. The team found that the polar transport system is required for root regeneration as well.
Interestingly, the team revealed that the defective LRs of some auxin signaling mutants can be recovered by root cutting, suggesting the robustness of the auxin signaling induced by root cutting. They also showed a redundancy of auxin biosynthesis genes by mutant analysis.

“We identified the primary gene of auxin biosynthesis which is responsible for root regeneration upon root damage. This finding could lead to the development of new methods for suppressing or enhancing root regeneration, and thus controlling plant growth in agriculture and horticulture,” says Masaaki Watahiki

More information: Dongyang Xu et al, YUCCA9-Mediated Auxin Biosynthesis and Polar Auxin Transport Synergistically Regulate Regeneration of Root Systems Following Root Cutting, Plant and Cell Physiology (2017). DOI: 10.1093/pcp/pcx107

Provided by: Hokkaido University

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