This Black Pine came to us in spring for maintenance pruning. It was too soon to do that just then (see post of 19th of April).
Now we are nearly two months later and the tree progresses well but it is still not ripe enough for pruning. Timing is one of the most important factors to be able to work on bonsai successfully. With this tree the maturity of the new buds determines when to start trimming, in this case within a few weeks. If the time of pruning is correct the results will be very positive after one summer.
Remember well: It is all about timing and observing and not just about pruning because it is in a certain month of the year.