wabashene

Japanese White Pine
Results of Care Survey

Over the past few weeks have carried out some research on the care of Japanese White Pine for locales Zone 7 or warmer in an attempt to come to some general conclusions about what can seem to be a mystery tree at times.

The research covered

A Bonsai Forum
2 major UK importers/ vendors
1 European Expert Site
2 Japanese Expert Sites
3 USA Expert sites

Topics studied/ asked about were:-

When to prune
Candle pinching when/why
Needle pulling when/why
When to wire
When to re-pot
Fertilising regime
Soil & watering regime

Findings

There was general agreement on soil & watering i.e. fast draining soil & watering carefully with the Europeans/ Japanese recommending pure medium/large grained akadama where of course it is cheap & accessible.

All agreed on wiring in late autumn up to early spring with only one recommending anytime.

All agreed on re-potting in spring with half suggesting late summer if necessary.

Also agreement on fertilizing to an extent. i.e. balanced type with an acidifying agent 2-3 times a year or regularly with 1/2 strength Miracid or similar. One major UK importer recommended an application of trace elements mid season.

Fertilizer type was different however with the Europeans and Japanese recommending rapeseed cake over manufactured chemical based types.

Two thirds (6 of 9) recommended heavy pruning for structure in winter/late autumn. One USA source said spring and one European said early summer. There was general agreement that light maintenance pruning could be carried out at other times.

Regarding candle pinching, some sources were more specific than others. The bonsai forum site and a USA expert site said take off 1/3 – end of story. (using the same source info?) Most of the other advice revolved around the general idea of pinching strong areas more than weak areas to balance growth and reducing strong areas to 2 buds. One UK site was very detailed about how much to pinch and where, dependent on how far back on the branch the shoot was.

One USA site stressed that candle pinching of JWP was the opposite of 2 needle pines in that you start with the strongest candles first to balance the energy.

Another USA site suggested removing all new shoots every other year if a tree was strong whereas one European expert was quite specific that a JWP should never be completely de-candled.

Does this constitute totally contradictory information?

Apart from this last point, we have nothing controversial really and the JWP doesn’t appear t be any different from any other pine species – so why all the fuss?

Only 2 of the 9 sources surveyed covered needle plucking specifically (1 Japanese expert and 1 UK vendor) and on questioning it turned out that the former had trained the latter!

The advice was to pull needles on strong shoots in winter to balance the tree’s energy and to thin growth to allow light into the tree, promote back budding etc.

On a personal note, the needle plucking regime was the hardest idea to envisage but now that I have done one tree once I’ve kind of got the drift.

This is not a totally exhaustive piece of research but may help Japanese White Pine owners or perhaps confuse them even more.

Does anyone have anything to add?

TimR

__________________
If I knew the way, I would take you there.

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