More banksias

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 found banksias to be very rewarding for bonsai. Why not have a try? Shibui bonsai normally has banksias available in a range of sizes including field grown trunks – see our banksia catalogue – hhttp://shibuibonsai.com.au/wp-content/uploads/2018/12/Banksias-2018-1.pdf

Trident winter pruning

Cold weather has finally come to Shibui Bonsai and many of the deciduous bonsai have lost leaves. I always find this a great time of year because I now get to see the underlying structure of branches and twigs that make up my bonsai. I now get the opportunity to assess the branch structure that has been hidden by a dense canopy of leaves for several months and to begin winter pruning and refinement. Continue reading

Japanese Black pines

The black pines have been growing slower than usual after summer decandling. It is possible that is a response to less fertiliser than previous years. I am pleased to have small buds on these pines but I’ll try to feed more often through next winter and see if that makes a difference next summer.

Here are the clusters of buds that are growing after candle pruning in mid December (early summer here). Note that these summer buds do not have the bare ‘neck’ that the stronger spring candles have. Not having bare sections means I can have much more compact growth and better ramification. Needles should also be smaller on these smaller buds which will add to the impression of a mature tree.

Continue reading

Trident nebari

Spreading basal roots, known by the Japanese term ‘nebari’ is considered very important for maple bonsai. Surface roots are prominent features of old maples, pines and elms so these features are also valued in bonsai of these species.

Nebari should, ideally, spread evenly all around the base of the tree, showing enough to give the tree the air of age and stability. Continue reading

Autumn pine work

The new shoots on Black pines have matured so it is time to thin out all the new shoots that have grown since decandling.

It is important to know that this is part of the technique used to REFINE MATURE pines. Younger, developing pines should be allowed to grow freely to gain strength and size and cut back hard every couple of years. Decandling is used to ramify the branches on trees that are closer to being mature bonsai. Continue reading

Twisted trunks

The first junipers I put into the grow beds were just allowed to grow freely. The result was stiff, straight branches that provided little inspiration, or opportunity, to create the sort of dynamic ‘wild’ junipers we see in Japanese literature.

About the same time Joe, nichigobonsai was talking about his experiences working in a Japanese bonsai nursery where they wired and bent large numbers of small junipers to start another batch of shohin twisted junipers. His comments showed me that junipers need to be treated differently to the other species I grow in order to produce inspirational bonsai stock. Continue reading