Uneven needle length


Hi, after decandling hoping to make the needles length shorter but instead, it gets longer after a few months, see attached pic for info.

I search the site but don’t seem to get the answer how. So can anyone pls. advise :slightly_smiling_face:



(Jonas Dupuich) #2

Two comments: If you want the trunk to grow larger, decandling will slow down development. If you want to keep the trunk the current size and add new branches, then this year is good for decandling.

As for what time of year to decandle the tree, June or July would likely be a good time. Here’s some info on decandling that might provide some context: https://bonsaitonight.com/2016/07/22/decandling-black-pine-bonsai-overview/


Also, did you fertilize a lot while the new needles were coming in? Fertilizer timing can affect the size of the foliage.


Hi SAL, no, i actually never apply any fertilizer on it.


Hi Jonas, actually i just want to keep the pine small and keeping the needles shortest possible. But instead needles grow longer after decandling :-).

can i just trim those long needles in the circle to control the length. Also, weahter here is always hot all round, there is no four seasons in my country :-).

(Jonas Dupuich) #6

Where do you live? Knowing your weather might help us recommend a protocol for reducing the needles.

Am also curious how pines naturally grow in your climate. Do the pines grow dormant at all, or do they grow year round?

(Frank Corrigan) #7

It would help to know the type of pine you are working with. Needle length will be affected by a number of factors as well as genetics.


HI Frank, I was told by the nursery it is a JBP from Japan.


Hi Jonas, it is always hot here in Singapore, a topical country. temp ranging from 27~33C (typ.).
Pin tree is not native and hardly you can spot them even in the garden/park and pine trees i spotted are not growing well (just my personal opinion, but i could be wrong).

(Jonas Dupuich) #10

Ah, I understand. There are a few things you can try. You can cut the needles so they are all the same small size. This will slow down the tree’s growth. You can also make sure the tree doesn’t stay too wet. Too much water will make the needles grow longer. Too much fertilizer after decandling will also make the needles longer.

It might help to focus on improving the branch density first and work on the needle length after you have more branches on the tree.

If you have more than one pine, you can try different experiments. It might help to decandle the tree two, or maybe three times a year if it is healthy.

(mac4) #11

I would add to Jonas comments. Over Watering: You live in a very high humidity area. Pines can absorb water from the atmosphere around them. A foggy night and they are taking water in. You need to monitor the watering more closely.

Branch Density: The more growing points the more energy that has to be produced to support them. If you have few growing points, that is candles, the amount of energy the roots produce is divided among them. I’m seeing four points, one a very tiny one where the trunk divides. If you increase the number of growing points, branch density, the energy is divided up between all of them. Same amount produced but spread out between more growing points to consume it. If you decandle the three bigger branches and allow two buds to develop on each of them then you’ll have seven growing points demanding energy to support them. The energy is not so concentrated in three buds and the needles will not grow as long.

Cutting the existing needles shorter should wait till you have new buds growing at the point you candle prune. Those longer needles will demand energy and make a little less available to the new buds that start growing. Once the new buds produce needles and they harden off then remove the old longer needles. This makes even less energy available to the new candles and hence shorter needles. When new needles harden off, get stiff, they cease getting longer. That’s when you remove the longer older needles.


thanks you for your advice, mac4 and it does sound logical to me, will think carefully to see what is the next step and circle back here later.


(mac4) #13

To monitor the moisture in the growing medium, I keep a standard bamboo chopstick stuck in the pot. When I am watering my trees I pull the chopstick out and look at it. If it is wet, I don’t water that tree. If has what I perceive as good moisture in the planting medium I don’t water that tree but will check it again later in the day. If it is just damp but with no medium clinging to it, I water then. Never let it dry out completely. It takes at least daily or in some cases twice daily checks of the chopstick to closely control watering. You can check the moisture in a pot very quickly and don’t need to dig your fingers down in the root zone to get a good idea of what you can’t see otherwise in the pot.

The chop stick is stuck in all the way to the bottom of the pot. By doing this you also can pick up on if there is water collecting in the bottom of the pot from poor drainage or deterioration of the planting medium. You’ll catch on quickly as to what the water needs are of each tree after a few days of checking that chopstick. Don’t ever assume that because the chopstick was wet yesterday it doesn’t need water today. Look!