Black Pine

Maggiolo72 wrote: Where do you live ? I am in the warm part of the Switzerland...
Just to have an idea about the timing

You should be a bit colder than here then (Italian/Slovenian border here, by the sea).
I have no JBP but I do have a JRP, and I decandle in early July.

Note however, that timing also depends on the goal.

In my case reduce needle size: you push decandling forward in the season so the plant has less time to grow new ones before approaching winter dormancy => smaller candles/needles in the second flush of growth.

If the only goal is to reduce strength on parts of the plant to reinvigorate others, timing becomes somehow less relevant.

Hi, the goal is mostly backbudding and reduce apex strenght

Btw I live in Basel, one of the most warmest part of Switzerland... We are really lucky here with the clima, Except these day where the weather is totally crazy