Cercidiphyllum

( ser - sid - ih - FILL - um )

At-A-Glance Information

Known commonly as the Katsura Tree or Caramel Tree, this genus of fast-growing deciduous trees needs full sun to light shade and regular water to perform well. Depending on the species, these trees can reach up to between 33 and 148 feet tall at maturity. Katsura trees have foliage that smells of burnt sugar, caramel, or cotton candy in autumn before leaves fall. These trees are deer-resistant and make great additions to many landscapes as shade trees, specimens, and do a perfect job adding color to fall landscapes.

Cercidiphyllum Species and Varietals

The genus Cercidiphyllum is the type member of the plant family Cercidiphylllaceae and includes just 2 species. The genus name refers to the fact that the trees in this genus bear leaves that resemble those of Cercis (Redbud). The best growing zones for Katsura Trees are USDA hardiness zones 4-8 or Sunset growing zones 2b-6, 14-16, and 18-20. To find your zone, click here: Zone Map.
Cercidiphyllum japonicum (Katsura, Caramel Tree, Japanese Judas Tree, Candyfloss)
​These trees are native to China and Japan, and reach around 40 feet tall. Katsura trees have a delicate branch and leaf pattern. New foliage is red-purple and mature to blue-green before turning light orange in the fall. Foliage of some varieties smells like brown sugar in warm fall weather and when leaves initially open in springtime. Some species are single-trunked, but most are multi-trunked, and all are vigorous growers.
'Heronswood Globe'
This variety tops out around 25 feet tall.
'Rotfuchs' ('Red Fox')
New foliage is dark purple.
'Amazing Grace'
A weeping variety of Katsura Tree; does not usually form a central leader and has a more rounded habit.
'Morioka Weeping'
This variety has pendulous branches and a strong central leader. Reaches up to 82 feet tall.

Cercidiphyllum magnificum (Large-Leaf Katsura, Magnificent Katsura, Caramel Tree)
These small deciduous trees do not usually exceed 32 feet tall at maturity, and have pyramidal to broadly cone-shaped crowns. Leaves are heart-shaped and emerge bronzey, maturing to green before turning brilliant shades of yellow, pink and orange red in the fall. These trees are most commonly seen as single-trunk specimens, and grow better in higher elevations than Cercidiphyllum japonicum trees.

Caring for Cercidiphyllum

Cercidiphyllum trees will grow best when planted in full sun to partial shade. For optimal fall color and performance, make sure these trees will be getting between 4 and 6 hours of sun each day. These trees thrive in areas with mild summers and cool winters. In warmer climates, Katsura trees may need some protection from late afternoon sun to prevent leaf scorch. These trees prefer soil that is loamy and well-draining, with a slightly acidic pH (between 5.0 and 6.5). Amend soil with plenty of organic matter such as compost before planting if local soils are clayey or dense; these trees dislike waterlogged conditions. Mulch the area under the tree with a 2-3 inch layer, ensuring that it does not touch the trunk. This will help suppress weed growth, retain optimal soil moisture, and manage soil temperature. Water young or newly installed trees regularly. Trees over three years old can tolerate some dry conditions, but overall will perform better with regular waterings during warm, dry periods of the year. These trees are drought-sensitive, and a lack of water for any amount of time can lead to leaf scorch or early leaf drop for the season.

Cercidiphyllum trees do not require much in the way of fertilization; in early springtime each year, simply apply a layer of compost around the base of the tree and work into the soil. Prune in late winter or early springtime before new growth pushes out for the year, removing dead, damaged, diseased, and crossing branches. These trees will develop beautiful silhouettes naturally, and minimal pruning is needed. They tend to sucker at the base when they reach maturity, forming a multi-trunked tree. In these cases, pruning to maintain a single stem is not advisable. Simply allow the tree to take the form that it desires; it will be much healthier. Katsura are considered very long-lived trees, and can survive in the landscape for hundreds of years before needing to be replaced if cared for properly.

Propagation

Cercidiphyllum can be propagated either by using cuttings or from seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the cutting method. If you would like to experiment and see what plant you can grow from seed, just keep in mind that it will not necessarily be the same as the parent plant. To propagate your tree or shrub, follow the instructions below:

Propagating Cercidiphyllum by Cutting
  1. Gather your materials. You'll need a clean, sanitized, sharp pair of garden shears, rooting hormone, a pencil, and a 3-inch pot filled with well-draining compost or other organic material. A good substrate for propagation of cuttings is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
  2. In spring or early summertime, choose the plant that you'd like to propagate. Ensure that this plant has had a good watering the night before, as this will improve the chances your cutting will take root. Cut one or more 6 inch semi-hardwood portion(s) of the end of a non-blooming branch  about a half and inch below a node and strip the leaves off of the lower half. Make a hole in your planting medium by pushing your pencil into the soil. Dip the end of the stem in rooting hormone, and plant it in your pot. Fill in soil around the cutting to support it, but do not pack it down too much.
  3. Moisten with water, and ensure that the pot has good drainage. Your pot should be kept in warm, sunny conditions indoors (and not in direct sunlight). Water whenever your soil is dry under the top layer. After about three to four weeks have passed, your cutting should be rooted. When you notice new growth, you'll know you have roots. 
  4. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring, when you can transplant it to its new home. Ensure that the last frost of the year has occurred before doing this, as it can seriously damage your new tree.

Propagating Cercidiphyllum by Seed
  1. Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. The best potting medium for seed germination is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
  2. Harvest your seeds. The seed pods are pretty easy to spot, they're large and form on branches, left behind after flowers have faded. Once they have dried out and begun to split open, you can harvest the seeds inside. Cut them off of the plant, placing them in a paper bag. Harvest as many as you can, and place the paper bag in a dry, cool, dark area. They will begin to split open and release the seeds contained inside. Once they have been released, take them out of the bag and put them in a container so you can work with them.
  3. Water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them with soil and water with your spray bottle. Place your tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window with a heat mat will do just as well. Germination usually takes about 10-20 days from sowing.
  4. Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home.
Katsura tree seed pods dry on the branches, and open to spill their seeds in fall and winter.
Katsura tree seeds are light and small, with wings on one or both ends which assist with wind dispersal.

Problems and Pests

Katsura trees suffer from issues with the following pests and diseases:
  • Purple Scale
​For more information, see the following pages:
​

Gallery

Katsura trees are lofty and heavily foliaged from spring through fall.
These trees make a statement against otherwise monotone backgrounds.
Katsura trees are beautiful, and their foliage will turn colors with cooling temperatures.
These trees have heart-shaped leaves, similar to those of Cercis (Redbud), though the two genera are not related.
These trees often form multiple trunks, and pruning out additional trunks is not recommended, as it can weaken the tree.
Foliage turns various shades of yellow, orange, red, and pink.

Videos

Learn all about these beautiful, fragrant trees.
Follow a Katsura tree through the seasons.
Learn all about Katsura trees from the Morri Arboretum.
Take a look at the Weeping Katsura Tree.
Watch the crew from the New York Botanical Garden move an established Katsura tree.

Resources

How to Take Care of a Katsura Tree
How to Grow and Care for Katsura Trees
How to Grow Katsura Tree
Wikipedia: Cercidiphyllum
The New Sunset Western Garden Book: The Ultimate Gardening Guide (2012) - Pages 232 - 233, Cercidiphyllum japonicum