Acacia bonsai - Africa's pride!

Acacia in the Pierneef open umbrella style.

The following information has been copied from

http://www.zululandbonsai.co.za/

(Additional personal experience will be added in bold.)

The most successfully grown acacia for bonsai are:

• Acacia burkei – black-monkey thorn / swartapiesdoring.

• Acacia caffra – common hook thorn / gewone haakdoring.
• Acacia erioloba – camel thorn thorn / kameeldoring.
• Acacia galpinii – monkey thorn / apiesdoring
• Acacia karoo – sweet thorn / soetdoring.
• Acacia nigrescens – knob thorn / knoppiesdoring.
• Acacia robusta subsp. clavigera – narrow-pod robust thorn / brakdoring
• Acacia robusta subsp. robusta – broad-pod robust thorn / enkeldoring.
• Acacia sieberiana var.wookii – paperbark thorn / papierbasdoring
• Acacia senegal var. rostrata - Driehaakdoring
• Acacia erubscens- Blouhaak

Roots – Most acacia have a tap root system which is not conducive to bonsai cultivation.  Shortening the tap root over a period of 2-4 seasons will force a number of adventitious roots to develop. In time, this will produce a workable flat root system. Although good surface roots are rarely formed by acacia. Pieter du Plessis is experimenting on using a washer to layer of the taproot on younger trees - the reuslts are very promising. After removing the dead taproot he is planting the trees on tiles.
Bark – Most acacia bark is rough and has a tendency to flake.  The exception to this is Acacia karroo, which has fairly smooth bark when young.
Trunks – Acacia trunks are usually flexible and single when young but at a later stage split into low, heavy branches.  Healing is relatively easy if the tree in encouraged to expand.  Pruning back will, in most cases, result in a crop of new branches. Tapering may be problematic as the trees carry only a few sparse branches at a time.
Branches – The branches are often mistaken for multi-trunks due to their size and the fact that ramification is poor.  The branches are known to weaken if they are grown in a descending manner.  It is therefore in the trees’ best interest that it is treated as it is in nature with a short trunk and low, ascending branches.  There should be no evidence of a definite apex, but rather a crown formed by a multitude of branch ends.
Leaves – The species has difficulty in forming a large number of small branches, but this is compensated for by compound, bipinnate leaf formation.  Each branch bears a long leaf stalk and a multitude of leaflets which take the place of fine twigs.

In January 2014 I took these pics of an Acacia with an amazing nebari - the biggest nebari I have ever seen on the species:

20cm high Acacia senegal var. rostrata 2 years in training in the Pierneef style:

Pieter du Plessis visited our Kai on 20 April 2013 and did a talk on Acacia. Here are some of the trees he brought along:

White Monkeythorn:

 White Monkeythorn:

 Black Monkeythorn:

 This Monkeythorn is 30 years in training and grown from seed:

 Black Monkeythorn 20 years grown from seed:

African Bonsai Styles
1. Baobab Style
2. Pierneef Style / Open umbrella Style
3. Flat Top StyleBushveld or Natural Style (Shizen-zukuri)

4. Bushveld or Natural Style (Shizen-zukuri)
Images courtesy of SA Bonsai

Celtis - from semi formal to flat top.

The self sown seedling in 2009:

I chopped it and picked up a new leader for a typical semi formal tree:

I decided against that and pull the twig down. I have decided on a flat top for now:

The tree January 2011 after a cut back and defoliation:

I am very happy with the direction I took with the tree. Except for some pinching I let the tree grow freely this year:

In early August  will cut it back, reduce the roots and pot it up for the first time. I am still deciding if I am going to use a slab, a hollowed out rock or a conventional pot.

November 2012:

 

 July 2014:

 July 2014 - cut back and ready to grow:

Umbrella tree (Schefflera) - one of my exotic trees.

This tree was growing in a clay pot but over years it's roots grew through the draining holes and eventually the pot cracked because of all the roots.

Here is the tree in the broken pot and roots growing into the paving:

Here is the tree removed but not planted July 2009:

I left some longer branches because I was still uncertain which direction to take this in but in the end decided to chop them and it was potted up after the roots were reduced. Here is the tree January 2010:

 Some more branches reduced and some carving done June 2010:

i could have shortened the tree more but thinking of making a open umbrella style crown and decided against that at that stage. Here is the tree(two views) defoliated January 2011:

From the last photo taken I have left the tree to grow freely. Will update soon.

The tree August 2012:

The tree has grown out well. Waiting for warmer weather before cutting it back and defoliating it.

October 2012:

 Cut back and semi defoliated:

Not very happy with the outcome. I should have cut back the long trunks a long time ago. I will repot the tree onto a slab and place the tree in the garden as a permanent display.

July 2014:

I have left the tree to grow out freely. It has formed a lot of aerial roots - will see if I am going to keep them. I am going to start feeding the tree for the cut back end August. Will update then.

Baby Jade (Portulacaria afra prostrate form)

This is a creeping (prostrate)form of Portulacaria afra:

 I removed the plant from the container by washing it out using a garden hose. This is the same plant today:

The variegated form:

I was also very lucky to get two variations of the upright form recently while on holiday in Eastern Cape along the roadside growing naturally. The cuttings were not planted for a month while on holiday but two cuttings survived:

The cork bark prostrate form:

The nodes are shorter and the leaves are smaller on the prostrate form. They cascade easily.
 Here is one I am trying in a weeping style(March 2013):

This species is untapped as bonsai and I believe we will see them becoming a very popular beginners bonsai- they are much better than the normal Baby Jade species- smaller leaves, shorter internodes and their trunks age much quicker.

Here is a progression on one of mine. (This plant is about 15cm high):

July 2009:

January 2010 in it's new pot:

May 2010. I am trying to pull the apex to the front - doing it very slowly because I don't want it to snap:

April 2012- Free growing for a few weeks and I am thinking of making this side the new front:

The tree today(March 2014):

(Still not happy with it!)
Portulacaria afra 2-Another fun project in a Baobab style:

March 2014:

My newest fun project, a Baoabab raft style Portulacaria:

My latest fun project using this species:

I used a thick cutting because I want the new roots to grab the rock tightly. I draped the rock with sphagnum moss to keep the cutting moist and  I have also wired the cutting to the rock to keep it stable.

I will let it grow wild for a while to develop strong roots. When I am happy with the roots I will start styling the crown.

Here is another root on rock project I am busy with.

The rock:

The areas I want to grow the cuttings:

The rock planted with cuttings:

Most of the cuttings were clued to the rock.

The planting in February 2012:

I have cut back the cuttings twice in 2013 and will start styling the individual trees in September 2013.

Two others I am working on(March 2014):

When the species is actively growing in warm weather it can take a lot of water. In winter I let the soil dry out before watering again.

When I transplant the trees in summer I cut the roots and cut back the top, pot the tree up in a dry mix and only water three days later. This prevents rotting.

Twigs can be cut back to the last opposite leaves - fine twigs may die back if no leaves are left. Luckily the tree bud back profusely and twigs can be shortened over time.

To reduce leaf size old leaves can be halved as soon as the new buds are visibly growing.

The species grow very easy from cuttings, especially if they are left a few days in shade to dry out.

The trunks will fuse if the outer cells are damaged and the trunks wrapped very tightly.