The following article has been compiled from the notes that I took when Marcus Watts first came to talk to us.
Many of the members are still finding difficult to get their head around the way to look after Chinese (soft needle) junipers, and are in some cases combining old with new due to confusion rather than being clever. Thankfully, our Chairman was kind enough to bring one of his trees along and allowed those who wanted to, a chance to practice. Many of the confused members reported feeling much happier, but things are always different when you get home again!
There are two main types of juniper, a soft foliage that looks like it has reptile scales for leaves (such as our club tree shown below, a Juniper Media Blaauw) and a needle juniper. Each requires very different pruning and training.
Chinese/soft junipers
Morten Albek wrote an article (see link below) Stop Hurting the Juniper! It is on pruning this type of juniper and clarifies how to prune the softer variety, often just described as Chinese Junipers. He gave me permission to put the link to his article on our site. Please click on it to read the article which is in English and is on the Shohin Bonsai Blog. He has also published an excellent book on shohin sized trees: Majesty in Miniature: Shohin Bonsai: Unlocking the Secrets of Small Trees, it is now out of print but must be pretty popular as it can still be found but at rather silly high prices, so worth a bit of searching around to find a more reasonable (used) copy perhaps.
http://shohinblog.com/2016/02/25/stop-hurting-the-juniper/
For both types repotting in Autumn is fine, as long as it doesn’t get waterlogged or frozen. Repotting in Spring can set the tree back 4-6 weeks.
Fertilising: We were advised to use organic fertilisers. In fact he almost felt that you could not overdo organic fertilisers. He stated that these can take up to 6 weeks to start having any effect so get it on early and keep topping up. If you are using chemicals however, be careful not to get carried away. If you have had the same wet summer that we have had, fertilisers will easily wash through the pots and so you think that you are feeding your trees well, but in fact they’re getting none of it. Consider protecting from rain if there are prolonged spells.
Soft junipers do not backbud readily, and certainly not away from an existing joint. You therefore have to view each branch as temporary, and always be developing the branch from within so that you don’t end up with a little pom-pom of foliage at the end of a long bare branch. At this point, half our members who were present were now in shock! Little did they know that there were more shocks to come!
The new shoots that we have all been so carefully removing from the joints over the years, are in fact the future of the branch! Choosing these shoots carefully will ensure that a nice branch will develop. Once this has developed sufficiently cut off the old branch. The next shock to everyone’s system was that we should not be pinching the new growth with our fingers. Pointed sharp scissors poked into the foliage to cut the little stems, is the way to go. Any particularly strong shoots can be removed at the base, however anything that comes “out of line” should be scissor cut. Pinching effectively kills that shoot off. The goal is to create new growth. Pinching back in the vain hope of backbudding is never going to work, as we have now learnt that soft junipers only throw shoots from joints! Keep feeding the tree until new shoots develop, and only remove the strong shoots. Try not to hit one area hard when pruning. The trees strength is in its foliage, not its roots.
When designing a soft juniper tree, think of rounded foliage pads, a rounded overall shape, and create smooth/rounded jins and shari. Sharp lines will not look right on a soft foliage juniper. Always plan 3 years ahead. This is important when considering displaying the tree, as with this planning you will not be able to display the tree year after year.
Remember it is not just about the branch you have now, but the branch that you are developing to take its place. This way you will always keep neat, compact growth, rather than a leggy branch with a pom-pom on the end!
Needle Junipers
Needle Junipers shown below, as the name suggests have needle like foliage. For design purposes, sharp lines, with jagged sharis and jins will work much better with this foliage.
Needle junipers are usually quite happy to backbud anywhere along a branch, but they are top dominant, and if you don’t keep this area in check, bottom branches can become weak and eventually die off. For this reason, you need to balance growth all over the tree.
In spring, do not be too eager to pinch off the new growth. Each shoot has a predetermined length (clever eh?!). So when you think that it has stopped growing, then using scissors, cut back the strong growths to 2mm (1/16″) from the base of the new shoot. This will encourage new buds to develop. You may want to leave the weaker growths all together. Prune off any unruly growth, pruning for shape at all times. On the buds that develop, pinch out the tips, and continue to pinch throughout the season until the tree stops actively growing. In our mild climate here in South Devon, you may only stop pinching off new growth around now (September).
Another important thing to remember about needle junipers, is that their sap lines (the pathway to get food from the roots to the branches) run almost in straight lines up the trunk. In other words, you will find a major root directly below each branch. If you were to remove that root, its branch is likely to die off. Unlike pines that are able to spiral their food around a trunk, needle junipers are not so clever! This is also an important consideration when considering creating a shari on a trunk. Making sure you do not cut off a food super highway is incredibly important when designing a shari. It also would mean that the live veins (those that feed the branches) would continue to swell, whereas the trunk would not. For this reason, do not create a shari until the trunk is the diameter that you want it.
South Devon Bonsai Society 