Koelreuteria bipinnata (Chinese Flame Tree )


Michael's Opinion

Koelreuteria bipinnata is quite the statement plant. It is known for its beautiful yellow flowers in the summer and pinky red fruit in the autumn months. The time that it is flowering and producing fruit far makes up for the months where it is only sporting its green foliage. They are not seen as invasive so it would be a lovely addition to any residential or landscape projects as it is quite tolerant to varying soil conditions. Its large spread crown is perfect to use for shade in parking lots, roadside plantings or even as a specimen plant as described earlier. It’s ability to grow almost anywhere that gets full sun and its natural aversion to almost all pests and diseases makes it extremely valuable. - Jayme Wallace

Botanical Information

FamilySapindaceae
GenusKoelreuteria
Speciesbipinnata
CategoryWoody
TypeTree (deciduous)
ReferencesGillman, E. F., & Watson, D. G. (1993). Koelruteria bipinnata Chinese Flame Tree. Forest Service Department of Agriculture. Bridwell, Ferrell M. "Chapter 10 Medium trees." Landscape Plants, Their Identification, Culture, and Use, 2nd ed., 2nd ed., Delmar Learning, 2003, p. 429+
OriginThis plant originated in Southern China. There does not appear to be any continental distribution (NC State Extension, n.d)
Ethnobotanical Uses
Disclaimer
The yellow flowers are used for medicinal purposes by creating yellow dye from them. The black seeds that come from the fruit are often used as beads for various religious ceremonies or celebrations. (UFEI, n.d) The papery fruit capsules are also dried and used for long term floral arrangements. (Edward F. Gilman and Dennis G. Watson, 2014)

Details

USDA Hardiness Zone7a - 9b
USDA Hardiness Ref.
Canadian Hardiness Zone6b - 9a
Canada Hardiness Ref.
RHS Hardiness ZoneH6 - H3
RHS Hardiness Ref.
Temperature (°C)-4 - -18
Temperature (°F)0 - 30
Height12 - 18 m
Spread4 - 7 m
Flowering PeriodJuly, August

Description and Growing Information

General DescriptionThe Chinese Flame Tree is a medium sized tree that can be quite widespread. It bears green leaves that have a beautiful yellow autumn colour. It bears yellow flowers in the late summer/early autumn, and it will also produce fruit with gorgeous pinky red paper like seed pods. The bark is smooth when young but becomes rigid as it matures. (NC State Extension, n.d)
ID CharacteristicIt is easily identifiable by its beautiful pink fruit seed pods which can be found in the autumn months and its large yellow flowers in late summer to early autumn. The rest of the year it can be identified by its compound bipinnate leaves with ovate shape and serrated margins, that are green or yellow in autumn. (Bridwell, Ferrel, M. 2003)
ShapeFor the most part this tree grows upright and has a round shape but on occasion you will find it growing spreading and open. (Bridwell, Ferrel.M, 2003) When the tree is young it tends to grow quite irregular but becomes symmetrical as it ages. (Gilman, Edward F, 1997)
LandscapeThis tree is used in a variety of different ways. It is pollution, salt and poor soil tolerant, so it is perfect for roadside and urban planting. It is also used as a specimen tree for its beautiful flowers and fruit produced toward the end of the year. It would be suitable for parks strictly for its beauty but also for shade as the crown can be quite wide. The tree is a benefit for wildlife habitat, as the crown can be used for shelter and the berries for food. (Edward F. Gilman and Dennis G. Watson, 1993)
PropagationScarify the seed surface by scratching the seed with sand paper. Soak the seed in water for a day before planting. This will help soften the outside of the seed and kick start the germination. Using a mixture of potting soil, peat moss, compost and sand or grit is the best medium when starting from seed. Misting the container you’re using helps ensure it gets the humidity it needs. Using a heat mat also helps the process as the temperature it needs should be at least 20°C. Germination should occur during the first 9 weeks. (Bonnie Grant, 2021)
CultivationThis plant loves to be in full sun. Its ideal soil condition is loam, sand or clay but will make do with whatever it is given (UFEI, n.d). It is also drought and pH tolerant which helps it withstand areas that get less water or areas with more acidic soil. (Bridwell, Ferrel.M, 2003)
PestsThere are no major pests to report. On occasion the older trees can be subject to root rot and the bark can develop cankers. Verticillium wilt is the common disease for this tree and can be terminal. Sadly, there is no solution to verticillium wilt. (Gilman, Edward F, 1997)
Notable SpecimensYou can find this stunning tree at The Margaret Grigg Nanjing Friendship Garden at the Missouri Botanical Garden in St Louis, Missouri, United States of America.(Missouri Botanical Garden, n.d)
HabitatThis tree is typically found in areas that can provide moist soil with clay, loam or sandy texture as well as lots of full sun. Although not native it was introduced to the United States of America in 1809 and is typically found along coastlines in California. It also enjoys deep watering so it would thrive in areas with excess water such as a swampy area. (UFEI, 2021)
Bark/Stem DescriptionThe bark is quite smooth when the tree is young, but it becomes rigid as it begins to age. It is thin and can be damaged easily. The bark looks anywhere from light green to light brown and develops cankers as it gets older in age. (Gilman, Edward F, 1997)
Flower/Leaf Bud DescriptionThe flower bud is a small ovate shape that comes to a point on one side. It grows a short green stem out of the end before the flower is produced. The bud looks to be quite smooth and displays a brown/red colour. They grow closely to one another so when the flowers emerge, they are in clusters. (Natusfera, n.d)
Leaf DescriptionThe leaves are green until they turn yellow in autumn. They have an oblong, ovate shape as well as being bipinnately compound and arranged alternately. The leaf margin is serrate and has pinnate venation. The leaf size ranges from 5-10 cm and starts leaf abscission in the autumn months. (University of Redlands, n.d)
Flower DescriptionIn late summer this tree produces gorgeous yellow flowers that have a pleasant fragrance and are quite showy. The flowers have 4 petals, are quite dense, grow in pyramidal clusters ranging anywhere from 20-50 cm in length. This tree also does a fantastic job at attracting pollinators like bees. (University of Redlands, n.d)
Fruit DescriptionThe fruit produced is elongated and oval. They can vary anywhere from 2-7 cm in length and the covering of the fruit is considered dry or hard. These pink, three lobed papery capsules have hard seeds on the inside growing anywhere from 5-10 cm. The seeds tend to drop and open on the ground leaving quite the mess. The paper capsules are quite the specimen though as they are often referred to as “Chinese Lanterns'' due to their shape resembling the Chinese lanterns that we all know. (University of Redlands, n.d)
Colour DescriptionThe leaves start out green and turn yellow during autumn. Yellow flowers bloom in the summer and pinky red fruit capsules also bloom in autumn. The seed that is produced is a black. The bark is a light brown or greenish in colour and stays the same throughout its growth. (University of Redlands, n.d)
Texture DescriptionFine-medium texture that does not tend to change over the course of the plant’s life or from season to season. (Bridwell, Ferrel.M, 2003)

Photographs