A couple of my smaller bonsai banksias started to develop dieback in some twigs toward the end of spring.
Many people would assume that, because these are banksias, the dead shoots would be the result of phosphorus toxicity. My experience with this genus led me to a completely different conclusion.
I have noticed that banksias have very dense fine roots that develop very quickly. Here’s what I found when this one was removed from the pot.
It definitely needs repotting.
First, trim back any long, fresh shoots.
When I cut through the root ball I found exactly what I was expecting – a dry patch in the middle.
That area is dry despite a thorough water last night and again this morning. The roots are so crowded that water has great difficulty penetrating which means the tree starts each day without a full pot of water. The dead shoots have nothing to do with P toxicity. They simply show a lack of water.
The remaining roots were trimmed quite a lot.
Note that there are no visible proteoid roots on this banksia because it gets regular fertiliser. Proteoid roots appear when banksias are short of nutrients and tend to disappear when the trees are fertilised regularly so paradoxically, regular fertiliser actually helps reduce the chance of P overdose for banksias.
Then back into the pot with fresh mix.
My experience with banksias as bonsai shows that the roots grow so fast that these need repotting every year to prevent them becoming root bound and having difficulties with water absorption. Fortunately they also seem very tolerant of the repotting process during the warmer months. This repot was carried out during a string of 40+C days in early January. New shoots continued to grow and more buds have sprouted since the repot. As usual, the freshly repotted tree went straight back to its usual position on the bench. The area is covered with light shade cloth this year but no other ‘aftercare’ was given.
I’ve been experimenting with natives for quite a few years now. In the last few I’ve tried speeding up the process by trialling a few species in the grow beds and the results are starting to come onto the sales benches.
This year I have a few Banksia integrifolia trunks ready for you to take to the next level.
All these banksias have been in the pots for just on 12 months. Please have a look and see if any of these look like the right tree for your next Aussie native bonsai adventure.
After a couple of tries I’ve finally managed to get photos of the new Shibui Bonsai field grown trees. Surgery on my right hand has curtailed other activities so I’ve also managed to format them into new catalogues.
Many of the tridents look a bit sad in these catalogues. Pictures were taken straight after their first trim for the season so they do look quite bare. I will try to update the photos as they bud up but, in the meantime, feel free to ask for new photos so you can check that the trees you are interested in really are healthy.
As usual, email neil@shibuibonsai with the catalogue description and numbers to check that the trees are still available and to discuss delivery costs. I’m more than happy to send extra photos if you would like to have a look at any trees from other angles.
Last weekend Ian from Alpine Art Bonsai and I put together another good display of quality bonsai to promote our art. Weather was fine and more people through the gates so we had even more stopping to ask questions of just to admire the trees this year.
The cooler weather this year meant that my azaleas were in full bloom for this weekend.
First place in ‘flowering bonsai’ category
A tiny cotoneaster cascade missed out on a place. Maybe the judge did not see it?
Ian’s Phoenix graft juniper received a prize in the single trunk competition.
This trident maple forest also caught the judge’s eye in the ‘group or multi trunk’ category.
Here at Shibui Bonsai we have a few large trident maples in the garden. As a result we also have a plentiful supply of trident maple seedlings every year. These provide an abundant resource for bonsai projects for both me, other members of out local club and Shibui Bonsai customers. Trident seedlings are available each year from June until I get tired of digging and packing them…………………. Continue reading →
Some of you may have noted the evenly spread roots on the trident maples in the previous post. Those of you who have been following for a while or who have been back through earlier posts will already be aware that nebari like that is not just a coincidence.
Here’s the same trident maple from below. The original trunk that was threaded through the hole in the aluminium plate is still visible and functioning. As it grows a little thicker, circulation will be further restricted and it will gradually die off but the new roots above the plate are now strong and healthy enough to support the tree.
The recent workshop with Joe Morgan-Payler has re-inspired me to keep developing these small, contorted junipers.
While not everyone appreciates this style of bonsai, especially here in Australia where our relatively mild climate does not produce such trees in the mountains, they seem to be valued by Japanese bonsai artists. These trees simulate the types of trunks that the severe winters and harsh growing conditions in the Japanese mountains naturally produce.
Today I worked on a Japanese Black pine. It was grown from seed about 10 years ago and I kept it because it has a really good 360 degrees root system that should develop into great pine nebari. Despite having such a great root system the top has not developed particularly well so I have not given it much attention so it is a good candidate to show how I go about making initial styling decisions. Continue reading →