I’ve had this Black Pine for about 3 years and the branches are starting to get leggy. The tree is far from refining and I need some guidance on developing the branches! Any feedback is appreciated!!
Austrian BP, or Japanese BP. Either way, watch the Mirai videos. Long needle single flush vs short needle multiple flush.
The quick summary is to pump it up and get it growing really strong to initiate back buds and then cut back the new shoots appropriately to encourage those back buds to expand. The videos have lots of great information, but I think Kurt was referring to long needle multiflush like Japanese black pine. They can become shorter needle with the appropriate technique, but are naturally long needled.
Thank you so much for the clarification. So should I continue to fertilize this tree from spring to fall for a few years? What NPK would be best for this type of development?
I wood fertilize fairly strongly (mostly if not all organic) for the entire growing season. This will pump up the tree and should drive the development of back buds. It will also drive the development of long needles, but what we need now is foliage mass to get the back budding. You can switch to fertilizer timing and candle/shoot pruning for shorter needles once you have more buds and shoots.