by
Grant Davison
In the Maple tree family there are numerous species which in their own way are beautiful trees.The Japanese Maple, Acer palmatum, has become one of the most popular smaller trees in landscaping today.These trees are highly regarded for their fall color and picturesque upright spreading vase shape.There is some important information regarding the planting of Japanese Maples that one should know about before planting it.When it comes to winter exposure, Japanese Maples are best planted along the eastern side of buildings or dense evergreen plantings.This will provide protection from the winter winds as well as the winter sun. The only exception to this is when they are surrounded by large established trees.Natural “microclimates” like these provide for warmer temperatures and less temperature fluctuation.
Japanese Maples also have specific soil needs.They must have a well-drained soil, which would result in fast and healthy growth, as well as more resistance to pests and winter injury.Before planting, it is best to add organic matter like sphagnum peat in a diameter of 5 feet around the tree.A three inch layer of mulch is needed after planting to provide moist conditions as well as winter protection for the shallow root system.Watering of Japanese Maples should be done uniformly throughout the growing season and more during summer heat.Major pruning should be done during the dormant season.
Propagation of Japanese Maple trees is done by seed and by grafting.Seed propagation is fairly simple and can be done at home by anyone.The first thing to be done is to collect the seeds from the tree.Seeds ripen in the fall and when they turn brown they are ready to be harvested.They will be attached to a wing, but it is best to break the wing off before storing or planting the seeds.The seeds of the Japanese Maple come with a very hard outer coating and if they are not harvested would take about two years to germinate on the ground.A person can improve the odds of germination and shorten the cycle by following certain directions.
Once the seeds are picked and the wings have been removed, place them in a bag and store in a cool, dry place until desired.About 100 days before the desired planting date, take the seeds and place them in a container that can withstand hot water.Pour warm to hot water on the seeds and let them soak for around 24 hours.At first most of the seeds will float, but near the 24 hour mark most will have settled to the bottom, then drain off the water.The next thing to do is to place the seeds in a plastic bag with a mixture of sand and peat.It should be moist but not soaking, then poke holes in the bag so there is circulation and finally place the bag in a refrigerator for 100 days. After 100 days the seeds can be planted outside (during the right season).To plant the seeds just sow them on top of a bed of well drained topsoil and cover with approximately 3/8” of soil.Water thoroughly, but allow the soil to dry out completely before watering again.
Once they start to germinate they need about 50% shade to keep from sunburn.
The other method used to propagate the Japanese Maple is by grafting.Some upright varieties that are known to hold their color real well are usually propagated by grafting a piece of the desired plant onto a small Japanese Maple grown from seed.For years the accepted method of growing Japanese Maples has been grafting and that is still the case today.
Below are some pictures of how to graft a Japanese maple onto another plant:
These
steps are basically what happens in a graft.A
thin piece of scion wood is grafted onto the rootstock of another type
of Japanese Maple.The
following list is comprised of a few different subspecies and descriptions
of the Japanese Maple or Acerpalmatum.
Acer palmatum:
-‘
-‘Bloodgood’-
Upright purple-red variety.Large
leaves hold color well through growing season.18’
tall
-Bonfire’-Leaves
start out crimson,go
bronze, and then turn fire red in the fall.Very
shrubby and reaching 12’ tall.
-‘Burgundy
Lace’- “Ribbonleaf” group with very lacy foliage.Foliage
is dissected burgundy red and will burn in full sun.12’
tall and 15’wide.
-‘Butterfly’-Leaves
are streaked with irregular blotches of white.9-12’
tall.
-‘Fireglow’-Foliage,
color, and growth similar to Bloodgood,
but fall color is more vivid.
-‘Kamagata’-Leaves
in spring are light green with red edges which fades to bright green and
in fall leaves turn yellow and orange. A
dwarf tree reaching 4-6’tall.
-‘Oregon
Sunset’- Red-leaved form with bright normal color.Dense
and 12-15’ tall.
-‘Red
Pygmy’- Dwarf plant with red-maroon leaves that are deeply divided.5-6’
tall.
A Fullgrown
Japanese Maple:
Basically
the only future work needed is to keep propagating these beautiful trees.A
new method of propagation is in the works called intermittent mist.There
was not enough information about rooting percentages or if any have even
germinated yet, but it is still in the trial stages right now.Maybe
in the future this will be the most productive method of propagation.For
now seed propagation and grafting are the two most commonly used methods
of propagation for the Japanese Maple.