Club News – August 2021

We are expecting to have about 200 trees and 50+ pots plus books, magazines and stands.
The Plant Sale Catalog will give you an idea of what will be available at the sale.

2021 Plant Sale

More information at – 2021 Plant Sale

Monthly Tasks

Each month there are a number of tasks you need to do to your bonsai – from repotting, to fertilizing to spraying for pests. We have put together a checklist, customized for the San Francisco Bay Area to help you. This checklist is adapted from earlier work by Mitsuo Umehara. 

This month: August Tasks

August and September are usually our hottest months here in the SF Bay Area. And now we’re in a drought again! Here are a couple of articles that might be helpful.

Summer Care – how to handle hot summer weather

Bonsai Care in the Time of Drought – some suggestions about how to care for bonsai during drought conditions

If you’re using timed-release fertilizer you should remember that it releases more as the temperature rises. Remove half of your timed release pellets to reduce the possibility of burning your trees.

Club Show Now Available

Normally at this time of year we’d be welcoming the public to our annual show at the Lucie Stern Community Center in Palo Alto. But as we all know this isn’t a typical year so instead we’d like to welcome you to our show online. 

Visit Our Show

Recap of July Meeting

As Idris Anderson said, Eric Schrader gave us a “very compelling” demonstration on styling a redwood at our July meeting. Eric has been working with redwoods for the past eight or nine years. He credits Tim Kong of BSSF for getting him started with this species.

Eric purchased his demo tree from Bob Shimon who is well known for redwood collecting. This tree has a unique trunk with a circular natural bridge feature to it which would have been buried when it was collected.

What is the best use of this material?

Eric with his natural-bridge redwood after styling
Eric with his natural-bridge redwood after styling
  1. Traditional straight bonsai with a “funky” trunk, or…
  2. Focus on the “funky” trunk and create a shorter tree

Eric chose option #2 and removed about 90% of the trees original foliage. He will wait until January to repot. By February it may be growing new foliage and Eric wants to time the repotting just before that happens.

When entering Big Basin from the North, you drive through groves of redwoods that have “weeping” branches on them. Eric chose to replicate this image in his design because this makes the tree branches match the old growth look of the trunk. You want the branches on a redwood to reflect the age of the trunk. So mature redwoods should not have branches going upward. 

In the future, Eric plans to create a new top for the tree starting at the left top-most branch seen in the photo above. Notice this branch is positioned to match the taper of the natural bridge of the trunk below. Eric expects to build about five to six inches of additional height to this tree over a course of the next few years. Eric will also carve off a portion of the current top of the tree and create deadwood that has an appropriate taper for the resulting tree. Eric says that normally you avoid adding height to your original composition but this composition is unfinished. It’s also challenging to fix a taper situation when you cut off the top of a tree.

Eric answered questions throughout his demo and left all of us much more informed about redwood care.

Pruning and Pinching Redwoods

Pinch tips of new growth while the new growth is still light green and soft. Mature foliage will have hardened off and be dark green. Pinch the new foliage by holding part of it with one hand and pinching (gently pulling) off the end with the other hand. You will want to remove from one-half to two-thirds of the new growth on the new branchlet. New buds should form at the pinch site and possibly further back. Elongation will also stop at the pinch site. Pinching causes compaction of new growth and a growth pattern that is visibly different. For example, needles will be opposite each other versus staggered on opposite sides.

Rather than pinch, you want to cut mature foliage. After cutting, it’s highly likely you will see die-back to the next junction along that mature branch or even see die-back all the way to the trunk itself. If at the trunk, you should get new buds on the trunk in that area. If at a junction, you should see new buds further back from that junction. Don’t be discouraged by this die-back.

When pruning redwoods, focus on what the foliage looks like versus what time of year it is. Redwood care doesn’t follow a strict timeline like pine bonsai care.


Eric uses shiny aluminum on young trees because it is visually easier to notice when the wire needs to be removed. For mature trees, Eric uses copper wire.

Styling and Controlling Growth

The arrangement of branches and the thickness of branches is critical on deciduous material. But for redwoods and conifers, Eric doesn’t think the thickness of a branch is as important as the quality of branch ramification and the placement of the branches with respect to the overall silhouette of the tree. If you do want to thicken a branch on a redwood, Eric suggested letting the branch elongate for a year and then shorten the branch and focus on ramification along that branch.

In response to Donna Farmar’s question about the eventual height and the apex of the tree, Eric said he likes height in redwoods and that carving out a redwood looks less contrived if you grow a new apex that is eventually higher than the carved area. Marsha Mekisich offered some comments about proportionality between upper and lower parts of the tree. And Charlene Fischer asked about grafting. Eric said this is certainly an option for this tree and that people should consider grafting more often. Grafting opens up so many opportunities to improve our trees that we normally probably don’t consider. Eric said he has even written an article about this subject. For redwoods, he recommends doing an approach graft. He also pointed out why other types of grafting don’t work well for redwoods.

While Eric said most people end up doing some carving on redwoods that they have topped, he himself is not a big “sawdust guy” and prefers to get assistance with carving from other more experienced bonsai enthusiasts such as Jay McDonald from BSSF among others. So don’t “not consider” carving if it’s a technique you’re not comfortable with. Just ask for help.

Going forward, you need to continue to remove new growth that is not part of your design, and make sure the desired growth is not shaded and gets the proper amount of sun. Allowing a clump of branches to come out in one place on a tree would also lead to an inverse taper forming at that node.

Soil, Watering, Sunlight and Repotting

When choosing your soil medium, Eric reminded us that we want to create a rootball that can survive in a confined location for a very long time and withstand the disturbance that repotting causes on that rootball. The soil substrate must allow proper air penetration and moisture (but not too wet) to equal areas of the rootball. When you alter the soil, you must also alter how you water and vice versa. Just bumping up the amount of akadama you use is probably not the best solution.

Most club members use a soil mixture of akadama, pumice and lava. But several members commented that they plant redwoods in pure akadama. Eric said he doesn’t use pure akadama because he finds it breaks down into “too muddy” a consistency by itself. But Eric lives in San Francisco where the maximum temperatures right now could only be 58 degrees. So things take longer to dry out there versus where most Kusamura members live in the South Bay. Eric plants redwoods in a soil mixture of 60-70% akadama and 30-40% pumice.

In response to Richard Murray’s question about misting redwoods, Eric said we wouldn’t go wrong by misting redwoods, especially on really hot days. Eric has installed misters underneath his benches where he keeps his redwoods. In nature, redwood foliage condenses the water from the fog and that drops down and waters/mists the redwood foliage below. So, anytime we can increase the ambient humidity around our trees is good because that slows down transpiration.

Michael Greenstein pointed out that there is genetic evidence that 50 million years ago the coastal redwoods and giant sequoias developed separate mechanisms for survival. Coastal redwoods (Sequoia sempervirens) require the presence of fog and only appear naturally in that environment. Giant sequoias (Sequoiadendron giganteum) require significant aquifers underneath them.

The Bay Area has a mix of many different microclimates. Your apartment or house even creates a differential within your local microclimate. Consider all these possibilities when deciding on locations for your trees with respect to wind, sun, shade, etc. It is not uncommon to have to move your trees around during the various seasons even though we predominately have only a wet and dry season in the Bay Area. The location of the sun and shade is always changing.

Eric recommends that we try to keep our redwoods in morning sun and afternoon shade, especially during the hotter summer months.

Propagating Redwood

Rooting redwood suckers didn’t work well for Eric but he has had lots of success rooting lateral redwood cuttings. 

Eric recommends propagating new bonsai material so we have more “hands on” opportunities to work on material that is not costly.

Shohin Redwoods

The pinching technique is much more important when working on shohin redwoods. For a shohin, Eric would cut a branch back to no more than an inch from the trunk. You want to force the start of ramification close to the trunk and maximize use of the limited space you have. Eric also said we need to be merciless when pinching and pruning shohin redwoods.  

With regard to wiring, only wire the primary branches to set the structure. Eventually you will wire secondary branches as you get them to the refinement stage. Be especially attentive to damage to the foliage when wiring at that stage. Wiring damage can lead to die-back also.

Soil Options for Less Mature Trees

Perlite mixed with coco coir is a good substitute for an akadama, pumice and lava mixture for young bonsai material that you want to grow vigorously. Eric has found that he can get three to five times faster growth in this scenario. Young plant material includes cuttings, seedlings, trees with smaller than desired trunk size, etc. 

Coco coir is ground up coconut husks and as an organic is more environmentally friendly than akadama. But coco coir breaks down much faster than akadama and that is not good for the roots of mature bonsai.

For mature bonsai you want controlled, moderately slow and predictable growth. Our club recommended soil mixture of akadama, pumice and lava is a mixture that is predictable and stable in the long term so you are not having to repot the mature tree too often.

Everyone enjoyed seeing the transformation Eric made to his redwood! And as Idris said, Eric’s presentation was very compelling. I know everyone looks forward to when Eric can return.

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