This is the time of year when we travel to the mountains to gather trees. It is also a good time to think about plans to repot your bonsai, cut them back, place styling wire, feed with 0-10-10. Leaves should be turning into fall color. Some will be brown and crisp while many will be turning red or gold. Move your trees to spaces where they get more sun.
Make sure you mark your calendar to spray with dormant oil in December and then again in January. This will stop most fungus and a lot of the small bugs that will want to attack your bonsai in the Spring. See you at the GSBF Convention in Sacramento!
We have experienced the very hot (100 degrees and above during the day with nighttime lows of about 75 degrees) weather of our typical July/August days. Some of the trees are suffering and some are happy about the heat. Maples, Elms, Crabapples, Oaks, Beeches and some Boxwoods will have brown leaves or the leaf margins will be burnt. Not to worry. Look for the emergence of small green buds below the damaged tissue and you will see them coming out behind the ones that are dead. Some bonsai people call this process defoliation without scissors.
On the other hand Pines, Junipers, Holly, Ficus and Pyracantha are quite happy as the heat gets hotter. The hot days and nights seem to agree with their individual needs and they tend to grow most when our deciduous trees are basically stopped. Just remember to water well. Take off the crispy leaves and the bonsai will look niceras the new leaves emerge.
Our president Paul has provided a lot of good information regarding summer care. I would like to offer a few more tips/observations that might help.
1). On a hot afternoon, say 103 at 4pm; if your clay pot is sitting in the sun the external temperature of the pot can be over 120 degrees and the inside of the pot above 130 degrees. This heated clay is right next to the most tender shoots that are feeding your bonsai. These feeder roots are killed by the high heat and although the tree is getting plenty of water it is still fading away. When those root tips (they are the white or cream colored part right at the very end of the root) die or are damaged it does not matter how much water you put into the pot it aint going to get into the tree.
Here are some suggestions:
Obviously the best solution if it is possible is to move your bonsai into an area with afternoon shade. – Get some material from a swamp cooler (it looks like a big sponge) and cut it out to fit over the pot and will reduce the temperature. – Wrap the pot up (don’t plug up the drainage holes) with an old rag or towel and it will help a lot. – Some people put ice cubes on their bonsai soil in the hot afternoons. I have not done this but heard that it works ok.
2). The EID is requiring me to reduce my water consumption by 30%, so while I continue to water the bonsai every day I have started watering the stock plants every other day. Many of them are wilting or dying from lack of water. My plan has always been to place the trees into a fast draining material and water frequently. Now that I can no longer do that I am going to have to plant my stock trees into a denser material with more organic matter, and Akadama, in it to retain the water longer.
3). For our smaller bonsai we have placed them into/upon large (20″x30″) bakers trays with Hyuga, or other fired clay, about 1″ deep on the bottom. The little bonsai sit in this wet rock most of the day and they seem to do quite well. It is not uncommon for us to lift up one of the little pots and find roots 18″ long growing out of the drainage holes and through the gravel.
Finally, each of us is faced with cultural problems that are unique to our own bonsai collection. Is the property flat or sloping? do you face east or west? are there big trees where you keep your bonsai? how do you water? what fertilizer do you use? how big is the pot in relation to the tree? and on and on.
The proper care and maintenance of bonsai is a lifetime learning adventure. Enjoy and see you soon
Shimpaku is also known as the Chinese Juniper, an excellent choice for bonsai. This evergreen is highly tolerant of various soil types. Interesting, Shimpaku is also dioecious, meaning it has separate male and female plants. This naturally, irregular shaped tree that grows in mound shape. The nice thing about using the Shimpaku tree for bonsai is the year round foliage with dark, green needles, beautiful to look at and soft to touch.
Because the Shimpaku is so easy to grow and maintain, it is perfect for beginner bonsai growers. With more than 500 species of evergreen in the Juniper category, you will certainly find the exact one that suits your needs. Typically, Shimpaku trees in Japan have been collected from mountains, dating back more than two centuries.
The Shimpaku does best in full sun although those with scale-like foliage do like a little bit of shade. In the winter, you want to protect the Shimpaku from frost. Although not recom- mended, when growing this type of tree indoors, the key is to make sure the tree has lots of good lighting, excellent humidity, and adequate air circulation. Without this, you would have a very difficult time growing it.
To water the Shimpaku, you want to keep the soil barely moist. Watering too much could lead to root rot, which is a problem the Shimpaku is prone to developing. In addition, you should mist the foliage several times a week to help keep pores free from dust in that this tree needs to breathe. To feed this bonsai tree, you want fertilizer every other week, containing high nitrogen. This should be done from the early part of spring to midsummer. Then from late summer through the winter months, feed the Shimpaku with low nitrogen fertilizer.
The Shimpaku needs to be pinched back continually throughout the growing season, helping to keep the foliage dense and compact. The key here is to use only your fingers, never scissors that would cause the foliage to turn brown. Then, do not pinch anything off one month after any visible growth is seen in late spring. Then, you want to thin out the foliage, helping to reduce the volume of older growth in the summer.
Now for repotting your Shimpaku, this should be performed every two years until the tree reaches age 10. At that point, you would only repot as needed. The best type of soil for this bonsai is soil that is free draining. Just make sure all stone or grit used in the soil mix is cleaned prior to using. This will get rid of any alkaline deposits that would cause stress to the tree.
To propagate the Shimpaku, you can air layer or use root ripe, woodcuttings in the fall. When it comes to styling for bonsai, the Shimpaku works exceptionally well with all styles with the exception of the broom. Then, this particular tree is virtually disease free. However, you would want to check occasionally for scales.
It is the time of the year when insects, diseases, and various fungus begin to use our trees for groceries. Each of these problems has a specific host that it prefers and a place it likes to occupy. There are literally hundreds of books on these subjects so I am just going to hit the high spots for what we find here in our nursery.
1). We who have oaks on our property will probably see little green worms hanging from fine silk threads. These are the larva stage of the oak moth. They will crawl around and make a green mess, eat like pigs and then build a small house where they change from a worm into a flying insect (the moth). The moths flutter all over the place, the birds have a feast, and then after the party the moths lay the eggs that will become next year’s worms — and then die. Ah…..the glory of life.
2). Aphids are quite happy to be gathering on the most tender parts of our plants. They don’t bother pines or junipers much but they love roses, crabapples, elms, oaks, and any other plant that is producing a soft green, new growth that is easily penetrated by their sucking mouth parts. Look around for shiny leaves that have sticky stuff on them (this is called honeydew and is aphid poo). Ants love the poo and the ants come with sooty mold fungus on their feet and then you have all kinds of problems. Mix 1 ounce of alcohol and about 8-10 drops of baby shampoo with 16 ounces of water and then spray; it will make them go away. Be nice to lady bugs; they are champion aphid eaters. Also praying mantis are voracious eaters of other insects.
3). Scale insects are very busy right now. They are difficult to detect because they don’t move around and are often given an appearance that makes them look very much like the bark they are stuck to. They live inside a hard shell and don’t respond well to insecticides. We use a toothbrush or small pick and squash them and then gently brush the area with Volck oil. Don’t get oil on any leaves and don’t use Malathion because both of these will burn your trees. Look closely where the branch leaves the trunk; look for a little bump that should not be there. If you can squish it, you have scale. If you see one scale there are always many more. Be vigilant.
4). Various mildews, molds, whorls, and other stuff will turn up from time to time. For these conditions and most fungus, the best offense is a good defense; so spray with dormant oil in December and then again in February. If you do this for a couple of years these kinds of problems will decline dramatically.
Those of you who attended our last meeting experienced how bonsai can be created from superior material. One of the things that we try to convince our new members of is: please try to acquire good material for your bonsai. Please don’t start purchasing a bunch of $25-$35 stuff in 3 gallon containers with the hope of turning it into a bonsai as soon as you find some time. It won’t take long for you to realize that you have set a trap for yourself. When you go out to water your plants after a year or two you will find that you have 50 small containers of potential (with the accent on potential) bonsai material, it is all you can do to water them and keep them alive, and instead of bonsai being a source of joy and satisfaction it has simply become another “chore” that somehow must be accomplished. Work with us to get fewer trees but focus on quality not quantity.