I have both grafted JWP and some on their own roots. I have several Zuisho and Kokonoe that on their own roots via layering. Several of my JWP appear to be seedlings.
They all pretty much drop their one year old needles. Maybe it’s because of my climate, fertilizing, and watering, I don’t know.
I give my pines full sun. They’re in bonsai pots, so their root growth is inhibited. They’re not over potted. All this contributes to moderate candle growth in the spring. Sure, some candles are stronger than others, especially those in the apex.
The approach I take is to pinch the too strong candles to make them match the weaker ones. If a terminal grows more than two new candles, I will reduce them to two in the spring. In the strong areas, I’ll remove the strong candles. In the weaker areas, I’ll remove the weaker “excess” candles. If there are two candles, and one is stronger than the other, I’ll pinch back on the stronger one to have it match the strength of the weaker one. If one branch produces stronger pairs of candles than the others around it, I’ll pinch both candles to have them balance out to be similar to the other candles all around. This is all spring work, done while the candles have just started to create the needles. Doing it at that time allows the tree to heal the pinched tip, and create terminal buds for next season. Waiting until later in the summer could cause a problem... the tree may not produce a new terminal bud.
Some varieties, zuisho and Kokomo, and others, are “dwarf varieties”, and they can produce many small buds at each terminal. I have to go thru them to thin these areas to two shoots.
It’s difficult to teach, “Do this, don’t do this...”. There’s so many variables. The various cultivars vary. Climates vary.
I’ve had to learn what works for me by working my trees.
