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The clothed lie about winter dormancy

By Carl Morrow

When one reads about bonsai activities in winter, it is quite easy to be lulled into a false sense of security that winter is a stagnant time with nothing to be done except drinking red wine, reading books and sitting next to the fire. This strikes me as being a very north European attitude where bonsai growers do have long periods of inactivity during their long winters.

Cape Town winters are short. They only get going in late May and then they are over by around August. It is a quieter time as far as growth of your trees is concerned, but there are still plenty of things to do. There is usually a lot of rain during this period, often coinciding with weekends. This limits access to the garden resulting in even less time available to achieve all of the important tasks at hand.

The first activity that needs to be done is preparation of soil ingredients for the soon to arrive potting season. Ideally this should be done before the rains start so that everything can be dried and sifted. I have certainly found that I run into tremendous problems come spring, when I don't have enough soil stocks for the trees that I want to pot. Your potting is delayed, and out of desperation, you resort to using unsuitable material for potting and end up regretting it for the rest of the summer season, because those particular trees don't grow properly for the whole year.

Winter pruning can be done soon after your deciduous trees have lost their leaves. What one tries to achieve with winter pruning is the refinement of the foliage structure in the tree. This pruning also stimulates the development of adventitious buds along the branches. When there are no leaves on the tree it is easier to see crossing twigs, conflicts in direction, branches that are too thick and areas that are too densely foliaged. I have found that looking down on a branch from above, while holding a sheet of paper underneath it (your hand also works very well), clearly shows the ramification in the branch and allows you to remove those twigs that are not fanning out properly. Occasionally deciduous and semi-deciduous trees hold onto their leaves through the winter. In this situation, Gail says that you should study the auxilary buds of the tree and if they are just swelling slightly then you can prune. Figs should be pruned later in the season. I have certainly found that a good winter pruning of a fig makes a tremendous difference to the neatness and compactness of the foliage masses. Further refinement can be achieved by wiring your trees at this time of year. The branches are swelling very slowly, although you need to keep a very close eye on the wire as spring approaches, because the tree can

suddenly start developing and you want to get the wire off the tree before it starts to bite too much. You should not wire the branch tips of Celtis as they are liable to die back if given this treatment.

During autumn and winter many trees shed their leaves that they no longer need. This results in a lot of leaf litter building up around the garden and on bonsai shelves. Add rain, cold weather, slugs and snails and one ends up with a horrible sludgy mess on and around your trees. This makes you trees appear even more miserable than they already look and it can also harbor bugs and disease that may emerge to infest your trees in the spring. It is a good idea to keep your shelves clean and weed free, so that pests, disease and weeds are not carried over from one season to the next. Something else that apparently makes a tremendous difference is winter spraying with dilute lime sulphur (mixed at a rate of 1 to 80, otherwise expressed as 12.5 ml made up to 1 liter with water). This kills off many hibernating problems and results in a much healthier collection the following summer.

Recently at a club meeting, I was talking to Rudi who told me, that he continues to feed his evergreen trees throughout the winter. This makes sense because it never gets extremely cold in Cape Town and so these trees (pines, junipers etcetera) do grow a little bit throughout this season. It would also build up their strength for the spring flush of growth. What Rudi does is, that he fertilizes more frequently, but with a more dilute fertilizer. The frequency is increased because of the rain that regularly washes the nutrients out the bottom of the pot. The fertilizer strength is reduced because the trees are growing slower and so they don't need as much nutrient. It probably would not cause too many problems using full strength fertilizer, it would just be a waste of money and chemicals.

Potting time starts when you least expect it! Come July you should start repotting your Celtis and the sequence after this is swamp cypresses, elms, maples and then the rest. Len carves and refines his deadwood at this time of year. You can also look at your stock trees and start deciding what possible designs can be achieved with them. You should also take the time to critically look at your established trees and decide whether they could be improved by changing branch arrangements, type of pot, potting angle or even something as subtle as potting height. The trees in your collection often develop imperceptibly and so you should periodically look at them in this critical manner so that you are not suddenly forced to do a major redesign on the tree that may set it back by a number of years. Another path of critical assessment is to bring your trees to club meetings and ask people for their comments. Not having seen the tree for some time, others often pick out small errors and problems that may have crept by without you noticing them. Obviously you don't have to slavishly follow their advice, you must decide for yourself whether the suggestions will improve the tree in your own eyes.

For some plants living in the South Western Cape, the seasons are quite different to that seen by us eurocentric individuals. Being a Mediterranean climate, plants are exposed to hot summer droughts and cool winter rains. Many indigenous trees have evolved in this climate by growing during winter and becoming dormant in the summer. One such example in my collection is the red pear (Scotopia mundii). This is also the reason for waiting for the first rains before olives and coleonemas are collected from the wild, although once they are in cultivation, I prefer to repot them in spring. Something else that always seems to happen during winter is that people decide since there is nothing happening all sorts of worthwhile bonsai and suiseki meetings get organised that take up even more of your time. I guess the conclusions that can be drawn from this discussion, are that winter in Cape Town is short and that there are many necessary activities which need to be done in preparing for the flurry of spring that will signal the start of a new and exciting bonsai season.

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Haiku

Last leaf has fallen

Tree will sleep and I will dream

Spring is tomorrow

Random Bonsai Tip

Tying roots - Rubber rings (approx one centimeter thick) cut from a motor car tube, have many uses. For example use to tie roots in a Root over rock planting - they also make good garters!