Caring for My Japanese Maples

November 13, 2024

This time of year, my grove of Japanese maple trees is aglow with autumn color - bright yellows, oranges, and reds.

Many of my Japanese maples are varieties of Acer palmatum - trees that have been cultivated in Japanese gardens for centuries. Over the last several years, I’ve planted many of these trees in one section of a shade garden not far from my chicken coops and tropical hoop houses. They were planted in honor of my late sister, Laura Plimpton, who adored these trees. These specimens provide countless variations in size, leaf shape, and color, creating a landscape of beauty and texture that gets better and better every year. This week, my outdoor grounds crew turned their attention to this grove, adding nutrient-rich composted mulch to each specimen, covering their bases just to the root flare, so they are all well-protected during the colder season.

Enjoy these photos.

: Every year, all of us here at the farm wait for this woodland to burst with color. With more than a thousand varieties and cultivars including hybrids, the iconic Japanese maple tree is among the most versatile small trees.

: Japanese maples are native to areas of Japan, Korea, China, and Russia. In Japan, the maple is called the “autumn welcoming tree” and is planted in the western portion of gardens – the direction from which fall arrives there. I love the contrast between the bright reds, oranges, yellows, and greens in this grove. The heavy leaf cover on the ground also enriches the soil and adds even more fall color.

: But those brilliant fall colors aren’t a guarantee. The colors are a result of climate, weather, and environmental conditions. Here in the Northeast, fall weather usually arrives in September, with temperatures cooling off rapidly at night even when the days are still warm. These cool nighttime temperatures trigger the leaf-changing process. Unusually warm early fall weather may even prevent the leaves from turning red. This is because the color changes occur with gradually cooling temperatures – not cold snaps.

: The deciduous trees above have already lost all their foliage leaving all the gorgeous colors down below.

: Leaf color best develops when nighttime temperatures remain above freezing but below 45-degrees Fahrenheit. A sudden cold snap could turn the leaves more plum-brown seemingly overnight, skipping the vibrantly red stage altogether.

: This year, the warmer weather lasted longer than usual, and it’s been unusually dry, but we’ve watered where necessary and these trees are still giving a good show.

: Red leafed cultivars are the most popular, followed by green shrubs with deeply dissected leaves.

: I also have more rare varieties. These leaves are deeply divided, but each lobe is also dissected, giving them a lacy effect.

: This compact Japanese maple has narrow, sword-like leaves that are deep red to plum in color.

: Japanese maple forms can be weeping, rounded, dwarf, mounding, upright, or cascading. Japanese maples typically grow about one-foot per year for the first 50-years, but they can live to be more than a hundred.

: Many of the Japanese maples with green spring leaves will eventually turn to an orange color in the fall. This orange can range everywhere between a darker burnt orange and a bright, almost florescent orange.

: With the right conditions, the fall colors of the Japanese maple may last for several weeks. Unfortunately, as it gets colder the colors begin to dull.

: My crew is busy adding composted mulch to the base of every Japanese maple in this grove. I am fortunate to be able to make lots of compost here at my farm.

: As each wheelbarrow is filled, Alex manually drops a certain amount around each tree depending on its size. The composted area around a tree should extend to the drip line of the branches, or at least cover a four to five foot diameter area around the trunk.

: The crew is doing this just in time. They noticed a couple of trees had lost soil around their bases caused by run-off. Composting now ensures all the trees will be well-protected during the cold season.

: Here, José uses a hard rake to spread an even layer around the tree base.

: It is important to only cover up to the root flare. The root flare is a swelling at the base of the trunk where the roots begin to spread out. It’s usually visible at or near ground level.

: When mulching, start the layer about four to six inches from the trunk and spread it out wide. The mulch should be just a few inches thick, and not mounded directly around the trunk.

: Adding composted mulch is good to do in spring and in the fall. Not only does this look great, but it prevents weeds, gives the trees essential nutrients, and insulates the roots.

: Looks great, José and Alex! This week, daytime temperatures dipped into the 50s, so it was good to get this task done.

: As the weather cools even more and daylight hours shorten, the leaves of the trees continue the autumn process of drying out, and falling off until the tree bare. And then come spring, new leaves emerge again.