is a busy time of the year in the garden.
There is a plethora of planting, including annuals, perennials, trees
and shrubs. The education staff is busy
teaching students all about our world and the plants inhabiting it. Live at the Garden is ramping up for a busy season, and weddings are constant. All of these activities are vital to the
garden and its continued growth, but in my humble opinion (granted that it is
VERY subjective), one of the most important tasks to accomplish during this
busy month is the pruning of the Japanese Black Pine.
| || Pinus
thunbergii is a gymnosperm (non-flowering plant) native to the coastal areas
of Japan and Korea, tolerant of the constant salt spray that accompanies these
sights. The needles on this pine occur
in pairs and are dark, lustrous green, ranging from 2 ½” – 4 ½” long, and
typically persist on the tree for 3-5 years.
There are a handful of cultivated varieties (cultivars) in the trade,
with one of the most popular being “Thunderhead,” but it is this gardener’s
opinion that the straight species is the most typical to come across, easiest
to grow, and the easiest to work with.|
of the pine trees located in Seijaku-En, The Japanese Garden of Tranquility
at Memphis Botanic Garden, are Black Pine, but we also have specimens of Pinus densiflora (Japanese Red Pine), P. strobus (Eastern White Pine), P.
parviflora (Japanese White Pine) and peripheral plantings of native P. elliottii (Slash
Pine) and P. taeda (Loblolly Pine.)
do we prune Black Pine during this busy time year you ask? The simplest answer is that the candles, new
growth, are elongating and we can control the trees growth, and more
specifically their direction of growth, by either shortening or removing
them. Candles on Black Pines typically
come in groups of 3-4, though on more aggressive areas of growth, such as the
top of the tree, you can see bundles of 5 or so.
why bother to prune the trees? For one,
it regulates the size. Black pines, if
left to their own accord, can grow to 40-50’ tall with long sections of
growth. The pines in our garden range
from 2’ -25’ tall, so we want to keep them small with more compact growth. Secondly, we want to style the tree in a
Japanese fashion in that they look similar to what you would see along a sea
coast; contorted by the constant harassment of the elements. This makes the trees look windswept, dwarf
and contorted. Pruning also helps different
parts of the tree either grow or not grow. Realizing that this might not make a whole lot of sense, let me
explain. The top growth of trees is
typically the most robust. It has the
most dominant leaders (growth) and receives the most amount of sun. By thinning (pruning) the trees, we open the
canopy up, letting rays of sunlight hit the lower branches and in turn producing
more growth. Having this more open
canopy also allows more air movement which helps with pest and disease issues. The overall effect of the pruning on the tree
is a dwarfing similar to what you see in bonsai.
have only scratched the surface of this whole process in this blog post. There are many other elements to consider
when pruning that are only learned through rigorous study and practical
experiences. If you are interested in
learning more on the art of pruning Black Pines, please feel free to contact me,
as I am always looking for volunteers. (I have a lot of trees to prune!!)