The Katsura tree (Cercidiphyllum japonicum) is a great shade tree with four season interest. It’s also a tree I WON’T let my wife talk me into planting at our new house (more on that below).
Katsura tree = Year around interest
The Katsura tree can make an excellent specimen or shade tree in landscapes. According to the green industry bible, the Manual of Woody Landscape Plants, this is one of tree guru Michael Dirr’s favorite trees. In fact, he likes it so much he says if he could use only one tree this would be his first choice.
I can understand why. It has clean fresh looking foliage throughout the growing season. It has an attractive pyramidal form when young that will spread as it ages. They also have good Fall color and an attractive bark.
Katsura trees provide interesting foliage year around
One of the best things about this tree is it’s foliage.
It has heart shaped leaves much like a red bud are only about a third of the size. It’s leaf color varies throughout the growing season to provide a source of visual interest in the landscape.
In the Spring, it’s leaves emerge reddish-purple. They then change to nice subtle blue-green color as they mature. In the Fall, they again change to a rich buttery yellow to apricot color.
Besides looking attractive, the Katsura has this neat trick of giving off a subtle sweet smell as it turns colors in the Fall. To me it smells like cotton candy.
What makes it more interesting is it hard to locate. You can pick up individual leaves and try to smell but you won’t be able to. Instead you smell it when you walk near the tree as it’s subtle aroma drifts through the air. I have to admit that it definitely adds pleasure to raking up their small leaves in the Autumn.
I imagine jumping into a pile of them from a large Katsura tree would be a joy for children (and adults) of all ages. So much so, I planted one at my old house just for that purpose. While it didn’t get big enough to make large piles of leaves to jump into, it did add the sweet smell to parts of my yard every autumn.
Hardiness Zones: Zone 4 – 8
Exposure: Full sun.
Mositure: Moist well drained soil.
Height: 40 – 60 feet
Width: This varies some trees may only get 20 – 30 feet wide while others will grow as wide as they are tall (40 – 60′).
Features: Clean disease free leaf foliage with Medium – fine texture and a blue-green Summer color. colored, sweet smelling fall foliage. Attractive slightly shaggy bark with age.
Growth Habit: Pyramidal to wide spreading with age
Fall Color: Buttery yellow to apricot orange.
Native: Nope, it’s not a North American native, it is from China and Japan. It grows in woodlands in Japan but in China it is mainly found in open areas with rich moist soils.
Wildlife value: Minimal. Not invasive.
Katsura Tree Care and Growing Tips:
The Katsura is a tree that like birches, must only be dug to be planted in the Spring. If it’s in a container or was dug in the Spring waiting patiently to be bought at a nursery, that’s OK and they can be planted anytime, but ideally they will be dug and planted in the Spring.
They do require well drained, rich and moist soil. If you have dry sandy soil, this is not the tree for you. Ditto with sun baked hard dry clay.
They are tolerant of different soil pH but they may have better fall color on an acid soil according to Dirr.
The key thing to remember is they will require supplemental water during hot dry periods for the first few years after planting. After they are established, they should only need supplemental water during droughts.
They can tolerate pruning fairly well (I had four at Anderson Japanese gardens that I used to take care of). I however think they look better if allowed to grow to their full size instead of trying to keep small to fit the scale of a Japanese garden. They do have a tendency to grow multiple trunks, so some training during their early years can help to provide a strong single trunk if that is the look you want.
The Kastura tree has several neat cultivars that might fit you landscape better then the species. These include:
Cercidiphyllum japonicum ‘Pendulum’ – This is a weeping form that will grow to 15 to 25 feet tall and a bit less wide than tall.
Cercidiphyllum japonicum ‘Morioka Weeping’ – This is another weeping form whose branches are more upright growing when young and has large leaves. It should grow to about 20 feet tall and 15 feet wide in a garden setting according to Iseli Nursery.
Cercidiphyllum japonicum ‘Heronswood Globe’ – This very interesting hard to find cultivar was introduced in 1991. It has dense globular habit. It is slowly growing to 15-20’ tall. I have seen this one and it has a rounded head form that looks like a miniature version of a full sized shade tree.
OK, so why won’t I plant one?
As a non native, it supports very little wildlife. This is a minus for me as well as others who are interested in supporting the biodiversity of our local wildlife. It is also a tree that is not drought tolerant (especially in it’s younger years), so it will require supplemental water during droughts.
Given my new small lot size and the fact I already have a large Honeylocust shading my backyard, I have limited space for shade trees. If I do plant a shade tree, it will be a native that supports our local wildlife.
So do you recommend the Katsura or not?
Although as a non native it does not support our native insects and the birds that feed upon them, there are cases where it is a good choice. Even though it is a non-native tree, it is highly ornamental that not only looks good but also helps our environment. For instance, the Katsura tree does:
- Provide shade which can lower energy costs and fossil fuel usage.
- Sequesters carbon through it’s growth.
- Lacks serious pests and is also from Asia so there is less likelihood of an exotic insect from Asian (like Emerald Ash Borer) devastating it due to total lack of resistance.
- Not require pesticide treatments.
- Not have invasive tendencies. So you won’t likely see it displacing native trees and shrubs in natural areas, unlike for instance the awful Norway maples (Acer platanoides) that nurseries still sell by the boatload.
So while the Katsura tree is not one I will be planting in my yard anytime soon*, it might be just the tree you are looking for.
*Well, maybe if I run across a ‘Heronswood Globe’ ?