Tree of the Month – September 2022

FEATURED TREE

 Pinus Thunbergii

JAPANESE BLACK PINE

Type: Japanese Black Pine is an evergreen conifer and is considered to be a two-needle variety of the Pinaceae genus.  

Style: Any style except broom.

Summer Placement: Full Sun. Spray foliage on hot days. 

Winter Placement: Protect against severe frost and cold winds.

Watering: Water when soil becomes dry. Water sparingly in winter.

Feeding: Every three to four weeks during the growing season.  Use acid-based fertilizers such as Miracle Grow. If you choose to feed more frequently remember to fertilize weakly weekly.  Use organic fertilizer cakes on more refined trees. 

Wiring: Wire in late fall into winter. Do not leave for more than six months.  Watch closely in the growing season and remove if wire begins biting into branches.

Pruning: Pinching and pruning vary according to the stage of development of the tree.  Younger trees may be allowed to grow more freely without a great deal of candle pruning or pinching while older, more refined, and ramified trees require more attention. 

With a more refined tree candle prune in March those candles are longer than 1”.  In June all new candles with needles at 45 degrees angle to the shaft are ready to be completely removed.  Leave ¼ “ stub on weak areas (inner and lower branches) of the tree. Thin needles of terminal candles to 2-4 sets of needles.  Depending on strength of the tree you may thin to 6-8 sets for weaker trees.  In late August to early September thin out new buds at each candle that was pruned to three or four buds.  In mid-November thin the needles of the tree for the winter by half depending on strength of the tree. (Quatelbaum)  

Repotting Season: Repot every three to five years in spring. 

Soil Mix: Use a free draining soil mix. Include some old soil containing mycorrhiza, a beneficial fungus that appears white in color.  

Container: Unglazed pot, slab, rocks.