　Satsuki and Other Trees in Mack's Garden 16

Renewal January 27th, 2013

The colour changes of leaves of satsuki

When you are growing satsuki trees, you can recognise that the leaves change their colours in spring and summer, and that they do so regularly according to the change of seasons. And you have to continue to watch their colours carefully once per day because they are the barometer of their health.

Section 1. When the colours of leaves change in spring and summer

When the colours of leaves changed in spring and summer, what do you recognise? In this case, you have to consider the reasons of injured health or your careless looking after them.

A. The health injured by insects and viruses

You cannot prevent insects and viruses injuring your satsuki trees if you didn't spray suitable agrochemicals regularly. Since they often are found in Japan, I buy 13 kinds of insecticides and 7 kinds of fungicides and make a plan to spray them once per 10 days at the start of a year. I always mix 2 kinds of insecticides with a fungicide. And if you watch them carefully everyday, you can keep them in a good health.

1. When you recognise that your tree has a lot of leaves of pale green or yellowish green, and find a lot of very small black dots on their undersurfaces, a lot of lace bugs already sucked the tree sap. And a lot of very small black dots are their dung. You can see them from May to October.

2. If you recognise that a lot of young leaves turn yellowish green, and cannot find small insects on both sides of them with your naked eyes in April, it is because a lot of extremely tiny insects, mites (Tarsonemidae), already sucked the tree sap. But after May, they are red spiders. In this case you have to spray a kind of special insecticide over them because general insecticides doesn't kill them.

3. If a lot of thrips sucked the tree sap of leaves, their green turns pale green, and they are rolled inside. If you don't spray an insecticide over them, their colour will turn brown.

4. When you recognise that your tree has a lot of pale green leaves and can find a small heap of wood particles at the bottom of trunk, you have to find the small hole on the trunk to kill a larva of longicorn borer, inserting a wire or pouring an insecticide into the hole. If you don't kill it, your tree will die. Sometimes it makes holes on the large branches. Especially it likes acer, maple and rose whose sap is sweet.

5. When you can find some brown spots on a lot of leaves, you have to spray a fungicide over them. If you don't do so, a lot of leaves will turn brown and fall down from the shoots. It is a black spot.

6. If you can find some parts of leaves black, you must spray a fungicide over them immediately. It is a dangerous disease, downy mildew.

B. The health injured by yourself

It depends mainly on your careless looking after your trees that all leaves turn pale green in spring and summer though you spray insecticides and germicides over them regularly.
1. Lack of water

Satsuki trees like water. When you see the young shoots of saplings and young trees bow, you can water them. It is OK. But the young shoots of bonsai are so short, especially after pruning, that they cannot bow, but can change their colour into pale yellowish green. Take note of this condition. If this condition is repeated three times, they won't have normal leaves: will have smaller leaves. It is clumsy.

It is in winter that a lot of satsuki trees die from lack of water. When your tree is lacking in water, if you cannot recognise that the colour of leaves turned a little bit pale green and don't water it, it would be very dangerous. It is because it takes some days for the colour of leaves to turn pale green after lack of water in winter. If the error is repeated three times, it will die.

2. Wet soil in the pots

Though satsuki likes water, don't keep the soil in the pots wet for a whole day. You have to give water to your satsuki trees which they can suck in the daytime. If you recognise that the colour of leaves turned pale green and that the pot is heavy, don't water it till the pot is light: don't give a lot of water to weak trees lest they should die. Especially repotted trees.

3. A lot of fertilisers

Sometimes you may recognise that the colour of leaves turned pale green though it had been dark green after giving fertilisers to your tree. It means that you gave it a lot of fertilisers. Remove all of them immediately. If you cannot do so, wash them away lest it should die.

4. Lack of fertilisers

If you recognise that the leaves of your tree are yellowish green and smaller than average, you have to give it a small quantity of organic fertilisers and do so again in three weeks. Don't give it a lot of them at once.

5. Agrochemical damage

If you follow the dilution ratio of agrochemicals, it is OK. If you don't, the young leaves of your trees shrink. Though it is too late for them to recover, you had better wash the deluded solution of some agrochemicals away. If you spray a very strong deluded solution of some agrochemicals, the tops of young shoots will be singed in two or three days.

Section 2. The green leaves changes into various colours in autumn

All satsuki trees have a lot of coloured cleaves in autumn, which fall from their shoots when winter comes. Especially some varieties have beautiful leaves which feature their colours of flowers which they will have next May. Therefore we can remove some shoots which will have unnecessary flowers next May to make a plan of colour arrangement of flowers. Though I introduced how to prune young satsuki trees, and how to take cuttings when they have multi-coloured flowers in my previous homepage, I would like to explain the meanings of coloured leaves about Asuka, Komei and Kogetsu.

A. Asuka

Judging from the flower theory of satsuki trees, you can recognise that this tree has all flowers that the variety of Asuka has to have. Since it is young and has the various flowers, it was easy to prune it because I didn't have to consider a colour arrangement. And these flowers are very beautiful. Besides half of them are white and small-striped flowers. Please remember the places of coloured flowers.

Height = 41 cm. The photo was taken on June 2nd, 2012.

Judging that this tree doesn't have a lot of red leaves which mean Fukurin (white jewel border), I can expect that it will have a good colour arrangement of flowers next May. But yellow leaves mean red and white flowers. Therefore the shoots which have red flowers have to be removed when pruning it after flowering.

Repotted in June. Height = 44 cm. Circumference = 13 cm. The photo was taken on December 7th, 2012.

B. Komei

These flowers are very beautiful, and the colour arrangement of flowers is good because my pruning after flowering was good and some shoots of red leaves were removed in autumn. But this tree has two branches on both sides which have all pink flowers. Therefore I mustn't make them large branch pads. And it has to have more white flowers than pink flowers and Fukurin than those on the below photo to have a good colour arrangement.

Height = 55 cm. The photo was taken on May 28th, 2012.

When you see the below photo taken in autumn, you can recognise the considerable number of red leaves on the top part of trunk. Therefore if I don't remove some shoots of red leaves, perhaps the top will have more flowers of Fukurin than those on the above photo. Besides you can see a few red ones on the felt first branch pad and the back first branch pad. It is strange that you can see a few red leaves on the left first branch, which mean Fukurin though it had only pink flowers on the above photo. Perhaps it will have Fukurin at the end of next May.

Height = 54 cm. Circumference = 13 cm. The photo was taken on December 7th, 2012.

C. Kogetsu

This tree has all flowers that the variety of Kogetsu has to have. Remember the colours of the variety on the photo. I think they are very beautiful, but a lot of amateurs prefer a tree which has more red flowers and Fukurin than this tree. If a young tree of this variety has more red flowers and Fukurin than this tree, four fifths of flowers will be red ones and Fukurin in several years. Therefore I would like to show you how to remove Fukurin in autumn and winter, judging from the colour of leaves.

Height = 35 cm. The photo was taken on June 2nd, 2012.

This sapling has four shoots which have green leaves, but other shoots are red and have red leaves which means Fukurin. Generally speaking, it isn't good as a sapling of bonsai because it won't be presented on the shelf at the flower show when it grows large. It is because it won't have all colours that the variety has to have. Therefore I remove all shoots now that have red leaves and will give it to one of our relatives when it has a lot of flowers because she likes it. But I think it will die soon after the flowers wither in her room.

Height = 24 cm. The photo was taken on January 19th, 2013.

You can see a red shoot which has red leaves on the below photo. At first I have to remove it. And next I would like to remove the shoot which has several red leaves and some large-striped ones. Perhaps it will have a flower of Fukurin next May. And other shoots have a lot of green leaves and some large-striped leaves. Therefore I keep all of them because these green leaves mean that these shoots will have red, white and striped flowers. This sapling is better as a sapling of bonsai because I will choose shoots which have good flowers next May to make multi-trunked bonsai.

Height = 32 cm. The photo was taken on January 19th, 2013.

These leaves are green. Therefore this tree will have a lot of white and striped flowers, and the small number of red flowers in the near future. Now I think it is the best of all of my saplings of Kogetsu. If I hadn't taken the new shoots by a red flower as cuttings, it never will have only red flowers in the near future. Or even if it has white and small-striped flowers next May, I will graft three or four saplings of red flowers on the branches when it is completed as bonsai.

Height = 31 cm. The photo was taken on January 19th, 2013.

Judging from the nature of Kogetsu, if we remove the unnecessary shoots of saplings or young trees in winter, we will be able to grow them as bonsai more quickly than when we prune them after flowering. We can expect to have a good result by pruning of them twice in a year. And the same concerning a lot of trees which have multi-coloured flowers.

When you sowed a lot of seeds of satsuki, you have to pick up all red shoots which came from the soil. You mustn't expect them to have good flowers.

And when the coloured leaves in winter began to turn to green leaves in spring again, these satsuki trees already sucked water and are making their new roots. Before then you have to give them fertilisers. Please watch them carefully.