The winter has been quite mild so far and this has confused many garden plants. For example I have a standard Azalea that has just finished flowering gloriously even though it should not flower until May time (see picture). It lives outside normally but the flower buds started to open in November and so I brought it into the conservatory to protect the blooms.
Make sure that flowers and/or fruit are removed so that trees and shrubs are not excessively weakened by attempting to set seed. If allowed to set and shed seed some trees may decide that they have done their job for providing the next generation and simply die.
I will have a lot of trees to repot in the spring and so I think that I will start to repot some of the evergreens such as junipers and pines, early in the new year. They will be fine as long as they are protected from frosts after repotting and it will give me more time later in early spring to repot the deciduous trees, once the buds start to swell prior to bursting forth into new growth.
For a bonsai tree to look its best it needs to be displayed in a good quality bonsai pot that suits the tree and compliments its colours and features. At NELBS we are fortunate to have China Mist Bonsai Pottery less than 50 miles away in Doncaster. Master potter, Steve Kitchman has visited our January club meeting for the last three years and has provided some extremely interesting demonstrations. He has brings pots along for members to purchase. On this occassion, Steve provided a demonstration on how to make a ‘slab’ for bonsai forest plantings, etc. This was followed by our members having the opportunity to make a slab of their own.
Although weather conditions and illness prevented a full turn out, ten slabs were made on the night and participants really enjoyed designing and making their own planting ‘slab’.
Right: Steve Kitchman of China Mist Bonsai Pottery is demonstrating how one type of planting slab is made.
As the meeting came to a close, Steve carefully packed members’ creations into his van to take back to his pottery for firing. We are all now eagerly awaiting a call from Steve to say that the slabs are ready.
The most common use of a slab is to plant a forest of bonsai trees. The quickest and often best way of creating a suitable group of similar trees for planting as a forest is to air-layer branches from a donor tree. Air-layering works on most trees but varieties such as acer palmatum and elms readily produce plenty of roots in quite a short period of time. The best time to air-layer trees is at the start of the spring, when the sap is starting to rise again.
Air-layering involves selecting suitable branches on the donor tree and removing a section of bark about the same width as the branch diameter. Rooting hormone powder is applied to the bottom of the cut-away bark and wet sphagnum moss is wrapped around the area and held in place by polythene or cling-film tied tightly at both ends around the branch. With some trees a good set of roots can develop within just a few weeks, allowing the branch (or branches) to be separated from the tree and to grow well independently.
By using the air-layering method to create a bonsai forest, it ensures that all the trees are genetically the same and should possess similar leaf size, colour, etc. I think that many of the club’s members will be air-layering this year to provide material for planting onto their new slabs.
Left: members creating their own forest planting slabs.
Now that the days are getting longer and the weather is getting a little warmer it is time to look at repotting certain trees. Once the buds on deciduous trees start to swell it is a clear sign that the sap is flowing again and so repotting should be considered. Some tree varieties benefit from regular repotting such as most Acer varieties as they produce lots of roots when healthy. Look for roots growing out of drainage holes or signs that the roots have pushed the tree upwards in the pot.
Before repotting have a good look at the tree’s position in the pot and decide whether or not it would benefit from a change of angle or sitting higher or lower in the pot. Also check if the ‘best front’ is positioned towards the viewer. It is also an opportunity to try to correct any issues with ugly and/or crossing roots and so take the opportunity.
You may decide to use the same pot for the tree but consider whether a different pot would suit the tree better; e.g. glazed pots coloured blue or green often suit flowering trees whereas unglazed dark pots often suit conifers.
You may decide to use the same pot for the tree but consider whether a different pot would suit the tree better; e.g. glazed pots coloured blue or green often suit flowering trees whereas unglazed dark pots often suit conifers.
Most trees benefit from the removal of any thick roots, particularly if growing downwards. However, be aware that you should not remove roots under the trunk area on Satsuki Azaleas as this will cause the tree to die from the top down (as I unfortunately know from previous experience). Roots growing around the pot can be trimmed and by reducing the overall size of the root ball by about a third to two thirds allows new healthy roots to grow into the areas containing the new growing medium.
Many soil mixes are used but it is essential to use an open mix that provides good drainage when watered and will absorb and retain water into the soil particles. After repotting, the tree will need protection for a few weeks from any frost and wind and must not be fed for at least four weeks, since any cut roots will burn and may damage or kill the tree. Look after newly-potted trees by regular ‘misting’ of the foliage and careful watering of the soil so that it does not dry out, whilst ensuring that it is not too wet. It is a good idea to place moss onto the soil of newly-potted trees to stop them from drying out.
May is a good month for bonsai enthusiasts as most deciduous trees have developed their fresh new leaves and flowering trees like azaleas and crab apple are starting to open their colourful blossoms. Watering and feeding are crucial to ensure that your bonsai trees stay healthy and mature into the established specimen trees for which you are aiming. Also, you need to ensure that you rotate your trees at least monthly to provide even sunlight to all parts of the tree.
Feeding regimes will depend on the development stage your bonsai is at. For instance if it needs to grow much more to allow it to be initially styled then a high nitrogen feed should be used about every ten days or so. Trees that are already styled but need to develop trunk thickness or branch ramification then a balanced feed should be used every ten days. You can extablish the balance of plant food by looking at the N-P-K numbers on a fertiliser packet; these letters represent various elements present in the fertiliser:
- (N) Nitrogen, used by trees to produce leaf growth and greener, lusher leaves.
- (P) Phosphor, used to increase fruit development and to produce a strong root system.
- (K) Potassium (Kalium or Pot-ash), used in flower colouration and size. It is also important to the overall strength of the tree.
Flowering and fruiting trees benefit from a feed content lower in Nitrogen but higher in Phosphor and Potassium, such as tomato feed. A balanced feed for example would be 10-10-10. The chemical analysis of a fertiliser is always in the order N-P-K (an internationally accepted convention).
When watering your trees you should allow the soil to dry sufficiently to allow air circulation in the soil but not so dry that the tree wilts and suffers. Equally, the soil should not be constantly wet as this will cause the roots to rot and die. Make sure that you water all parts of the soil evenly to prevent dry spots from forming, especially in the corners of rectangular pots. During hot periods it is a good idea to occasionally submerge the pot in a container of water for about half an hour to ensure that there are no dry areas in the soil and to allow the tree to replenish any dryness in the roots and cambium layer.
A tree with cones forming. Larch roots are prone to rotting if kept too wet. I feed the tree with a tomato feed from spring until late autumn to help feed the growing cones.
A tree mainly grown for its flowers and fruit. This tree likes plenty of water and a high phosphor and potash feed to help the flowers to form and the fruit to set.
Azaleas have very fine roots that like to be kept cool (hence the deeper pot). They like plenty of water and a high potassium feed for the flowers. If fed with too much nitrogen then potential flower buds are likely to revert into new foliage.
Writing this blog on the 1st of June it is cold, very windy and sheeting with rain. ‘Flaming June’ as it is locally known!
Well, so much for that so far! I just hope that it picks up soon, as we need some warm weather to provide a decent growing season for our trees. When I saw the weather forecast, I moved a few trees from their exposed positions in the garden to more sheltered areas.
One area that I use is somewhere that all serious bonsai enthusiasts should consider providing: a netted bonsai area. I built mine a few years ago using inexpensive materials and it has been really useful. It measures eight feet (2.5 metres) by ten feet (3.0 metres) and is clad in green windbreaker netting. I managed to get hold of some that had been used on a construction site. It cost me a couple of pints of beer for a builder mate who ‘liberated’ it from being thrown away after a job on which he was working. You can buy this kind of thing by the linear metre from most garden centres. I stretched it across some hardwood tall posts so that I can comfortably walk around inside it. I bought a few breeze blocks and some lengths of treated roofing lathes to construct shelving around the perimeter and down the centre. I found that in the winter, snow settled on the netting roof and eventuaklly fell in. To rectify this I wove fencing wire in different directions into the netting roof and fastened it by tensioning it between the posts. So far, it has managed to hold the weight of snow that has fallen over the last three years.
As well as acting as a very effective wind shelter, it is also an area where I keep maples that not only dislike wind but also benefit from partial shade. In addition, I find that it helps my flowering trees to keep their flowers for longer. This is very useful if we have a bonsai show coming up and I want to extend the flowering period, to ensure that my flowering trees can be shown. Another use for the bonsai netted area is that after repotting trees, they need to be protected from the wind to prevent any tree movement, which would prevent the new roots from developing properly.
Some of the trees that I currently have in my netted area are: Kiyohime Maple, Arakawa Maple, Deshojo Maple and Dissectum Maples. Flowering trees include Satsuki Azaleas, Hawthorns, Rowans and Ceanothus.
Space permitting, a netted bonsai area is a must for anyone wishing to grow and successfully maintain bonsai trees.
On Sunday the 28th June our club put on a display of members’ trees at Grimsby Garden Centre. The club has put on a display at this garden centre for many years now. Every year we wonder wether it is worth all of our time and effort but every year we have a good response from the general public about the display. It is a long day and many members bring trees to show each year and I think that we always manage to put on a good display.
I think it is something we need to continue doing for many reasons; it helps to promote the hobby to the general public and members answer lots of questions about the trees, helping to dispel many myths people seem to have about bonsai. The display also allows members to prepare their trees to a good standard for showing and to gain a sense of pride for the hard work that goes into growing and styling their trees. This helps to build confidence, team working and co-operation between club members. Most of all, it usually leads to the club gaining new members as a direct result of putting on the display.
Every year we meet local people who have often grown bonsai for years who did not know that a bonsai club existed in the area. This year we tried something different and put on a small display of trees in their early development stages, showing how trees can be cheaply created from common ‘garden centre’ material. This was successful in helping to demonstrate that exotic bonsai do not have to be imported from the Far East but that cheap British shrubs and trees can and do make excellent bonsai that thrive well in our climate. Many people we speak to say that they had previously purchased a bonsai, typically from a supermarket, that died within a couple of weeks. This makes people think that growing bonsai is a specialist thing and too difficult for them to undertake. We are able to explain about the correct care, placement and watering requirements and encourage people to give it another chance and even join the club to learn far more about this very rewarding hobby.
On the same theme as the August blog of John Willis I am very concerned this year about a garden pest that can kill bonsai trees if allowed to wreak their havoc. The particular pests that I am talking about are vine weevils, or more specifically the larvae of vine weevils. The adult vine weevil looks like a muddy brown beetle and similar to the leaf cutting bee that John Willis describes they take large pieces out of leaves. Often the first sign that you have vine weevils around is when you see large chunks missing from the edge of leaves. The adult weevil is usually active at night and so searching at night with a torch on any damaged plants is a good way of finding them. The adult damage is superficial compared to the damage done by the little white grubs that hatch out in the soil. The adults can lay hundreds of eggs into the soil near healthy plants and when the larvae hatch they feed vociferously on the roots. The problem is that you often do not know they are there until it is too late and all the roots have been eaten resulting in the death of the plant.
This year I noticed the tell-tale vine weevil leaf damage on several plants in my garden. Often vine weevils will avoid laying their eggs in open gritty soil mix such as that used for bonsai. However, I found some adult weevils hiding on a couple of my bonsai trees and also a suspicious looking hole drilled into the soil of a favourite bonsai crab apple of mine. So, what can I do about it? Well, I have bought a treatment specifically for killing vine weevils and their offspring. It has to be well watered onto the soil to thoroughly drench it in order to be able to kill any grubs. The vine weevil killer is not cheap though and as I will need to thoroughly soak all my trees (about 80 trees in total!) the costs could potentially be quite high as most of it will drain out the bottom of the pots. To reduce the waste I will use two large plastic troughs. In one trough I will place as many trees as possible and soak them thoroughly in the vine weevil killer treatment. After a good soaking I will move the trees into the second trough so that any excess treatment drains out but will be retained in the trough to use again on the next lot of trees. Hopefully this will minimise the amount of waste whilst ensuring that all the trees receive a thorough soaking. The treatment remains active for up-to six months and so I will repeat the treatment again in the spring.
Well here we are in September and autumn is nearly with us. It is a time in the garden when fruit and vegetables are ripening. It appears to be a good year this year for fruit as my apple and plum trees are really heavily laden with fruit. Also my bonsai crab apple has a really good crop of rosy red apples. The autumn change of leaf colour has also started with trees like larch and maples starting to glow yellow and red in places.
I have started to purchase a few concrete pillars to display some of my trees on. I have a contact who is making the stands for £25 each. I know that fencing posts or telegraph poles are a bit cheaper but they don’t have the same classy look as the white concrete pillars. I use elasticated bungee straps to secure the trees to the pillars so that the wind does not blow them off. The concrete pillars are quite heavy and so they should be able to stand the winter winds, although when the really heavy winds start I will probably take the trees off. Anyway, time get stuck in to a nice plum and apple crumble.
I am writing this month’s blog 34 thousand feet up in the air on board a Boeing 737-300 on my way home from holidaying in Madeira. Whilst there, as whenever I visit a warm climate country, I really admired the many varied and different trees around. I particularly admired some of the brightly coloured flowering trees with orange, red, pink, purple and yellow magnificent flowers. I have previously tried collecting the seeds from some of these amazing trees in the futile hope of being able to grow them back in the UK, even maybe as bonsais. Of course one of the main problems of growing most of the flowering trees is the fact that you cannot reduce the size of the flowers or fruits and so they would look silly as a small tree. Reducing leaf size is possible but when it comes to flowers and fruits nature will always win. Bougainvillea of course produce brightly coloured bracts (modified leaves) that most people think are its flowers. As they are a type of leaf they can be reduced in size and made into quite an attractive bonsai.
I only have three bonsai trees that will not stand being outside during a British winter. A bougainvillaea, and two different types of ficus trees. I keep them outside during the months when the danger of a frost is unlikely, and as soon as the weather starts to change I bring them inside. The bougainvillaea provides some real colour during the winter months with its bright red bracts and small white flowers. The ficus trees however are quite dull and I sometimes wonder why I bother with them. One is a twisted trunk small leaved ficus that a friend was going to throw away as it had been left in a cold porch and as a result part of it had died. I decided to rescue it and I have kept it alive for the last 15 or so years. The other is a larger leafed ficus that someone bought for me from a local garden centre at least 20 years ago. It has a trunk that resembles my belly, but other than that no real endearing features. I suppose that they are a little bit like an old comfortable jumper that you have had for so long that you just can’t bear to get rid of! Maybe I should put them on Ebay or something.
I can’t believe that November is here already. The summer was too short and seemed to pass me by. Now most of the trees’ leaves have fallen in the garden and we have short damp and cold days ahead of us.
I have been laid up with a back problem that seems to start playing up at this time of the year for some reason. It has resulted in my having to delay basic, but important jobs in the garden. For example, I have quite a lot of grass that needs cutting regularly and the back problem has delayed my getting it done. Also I like to give my netted bonsai area a good clean out once all the leaves have dropped. This helps to reduce the hiding places that bugs and garden pests have in which to harbour over winter.
One advantage of leaf fall time on deciduous trees is that you can clearly see the branch structure. It is therefore an ideal time to prune back and reshape your trees. It is also a good time to clean any moss, lichen and other debris from trunks and branches. Fig 1 (right): Cleaning up a tree’s skeleton also helps to reduce the risk of any bugs and/or diseases over-wintering on it.
At our last club meeting we had John Armitage demonstrating how to style a Shohin juniper and plant it onto a rock. As usual, John provided a very good demonstration and gave us lots of useful hints and tips. One thing that John mentioned was how in Japan they use very fine high pressure water jetting to clean their bonsai trees at this time of the year and to prepare them for showing. John mentioned that a similar device is available to buy on Amazon for around £50. I searched on Amazon and found the Wagner W-180P Set Electric Hand Spray Gun 150 Bar With Accessories for £53.50. It can also be used to spray paint, clean car wheels, remove loose paint and rust etc. John Armitage has confirmed that this is the spray gun he mentioned and so I am now considering purchasing it. If I do so I will report on how effective it is in future blogs. It can be found HERE.
On Saturday 20th November five of our bonsai club members went to Castle Howard to dig up some young trees. This was not an act of theft or vandalism, it had been organised with the Castle Howard Forestry Manager, Nick Cook. Nick initially talked us through how they collect seed from some of the trees on the estate and about the process of stratification. He then took us into the fields where various seedlings were growing. Nick explained that each year they under-cut the trees using a special machine to remove the tap roots and to encourage a more fibrous root system (ideal for bonsai). The trees included larch, pines, yews, hawthorn, crab apple, field maples and many others ranging from this years seedlings to six foot high trees that were several years old. Nick allowed us to dig up any trees we wanted for 25 pence or so for each tree, depending on the type and age. The day was very interesting as Nick provided lots of useful information about stratification, chitting seeds, growing conditions, pests, diseases and much more. Some of the trees will be on sale to our members at the next club meeting when we will have a bring and buy sale.
In last month’s blog I wrote about a high pressure spray gun that John Armitage had recommended for cleaning bonsai trees. I was lucky enough to be bought one of these recently and I can report that it works really well. Figs 1-3 (left): Before, during and after treatment
I used it on a larch tree that has lots of lichen growing all over the branches that I thought would be a good test for the sprayer. It blasts off any unwanted detritus very effectively as it can produce up to 150 bar (over 2000 psi) of water pressure in a small water jet.
I adjusted the pressure setting so that it was just high enough to remove lichen without damaging the dormant buds. It is also great for cleaning jins and shari that have turned green. I will be giving my trees and pots a good clean over the winter period whilst they are dormant. Figs 4-5 (right): Before and after treatment.