When Does the Paulownia Tree Bloom? A Full Guide to the Latest Blooming Periods
The paulownia tree, also known as white-flowered paulownia, big-fruited paulownia, hollow paulownia wood and so on, is a deciduous tree of the genus Paulownia in the family Scrophulariaceae. It grows fast, is widely distributed, has good-quality wood and many uses, and is suitable both for greening around the four sides of villages and for block afforestation, as well as for building farmland shelterbelt networks and crop-paulownia intercropping across the vast areas of North China and the Central Plains. Let us take a look below at when the paulownia tree blooms!
When does the paulownia tree bloom?
The paulownia tree usually blooms from March to April, and the blooming period lasts about 1 month. The paulownia flowers are borne 3 to 5 together in small cymes, with or without a common peduncle, but because the leaf-like involucre and bracts from the winter drop off, most of the small cymes form a large inflorescence. The lateral branches of the inflorescence axis vary in length, making the inflorescence conical, pyramidal or cylindrical. The corolla is large, purple or white, funnel-shaped bell-shaped to tubular funnel-shaped, with two longitudinal folds on the belly (only the white-flowered paulownia has no obvious longitudinal folds), often with dark purple spots inside, and yellow at the raised part of the longitudinal folds.
Growth habits of the paulownia tree
The paulownia tree is a sun-loving species, growing best in well-drained sandy loam or gravelly soil with deep soil layers and good aeration. It prefers moist, fertile soil, with a pH of 6 to 8 being best, and tends to selectively absorb elements such as magnesium, calcium and strontium. Paulownia has strong adaptability and can generally grow in strongly acidic or strongly alkaline soil, or in relatively barren low hills, hilly areas or plains, but it dislikes waterlogging. Its temperature tolerance range is also fairly wide; in the north it can withstand low temperatures of -20°C to 25°C, and it can grow from southern Liaoning in northeast China, North China, Central China, East China, South China and the southwest to parts of the northwest, with species adapted to the local ecological environment found in every region.
Variety classification of the paulownia tree
1. Southern paulownia: The southern paulownia has a conical or broadly conical crown, heart-shaped circular leaves, and the underside of the leaves densely covered with dendritic hairs and sticky glandular hairs. The panicle branches are broad and large, and the fruit is elliptical, setting much seed. It is distributed from Zhejiang and Fujian in the east through Jiangxi to northern Guangdong and Hunan, as well as the mountainous areas where the four provinces of Sichuan, Hubei, Hunan and Guizhou meet. It grows wild in the hilly and mountainous areas of Zhejiang, Fujian and eastern Sichuan.
2. White-flowered paulownia: The white-flowered paulownia has a straight, tall trunk, long ovate heart-shaped leaves, and the underside covered with long-stalked dendritic hairs. The inflorescence branches are narrow and small, forming a cylindrical or narrow conical shape, and the corolla is white or light purple. The white-flowered paulownia is the most widely distributed species in the south, found throughout the area south of the Yangtze River, from Taiwan in the east to the Gaoligong Mountains at the westernmost part of Yunnan in the west, and south to Guangdong and Guangxi and on to northern Vietnam and Laos.
3. Catalpa-leaved paulownia: The catalpa-leaved paulownia has a relatively straight trunk and a small branching angle. Its leaves are long ovate heart-shaped, nearly twice as long as wide, and the underside is densely covered with short-stalked dendritic hairs. The inflorescence branches are conical or narrowly conical. It is distributed from the Jiaodong Peninsula in the east, along the Yellow River basin through the Taihang Mountains and Zhongtiao Mountains south to the mountainous areas of western Henan, and west to the lower reaches of the Luo River in Shaanxi, reaching Beijing in the north and the Huai River basin in the south.
4. Lankao paulownia: The Lankao paulownia has a trunk of the intermittent trunk-extension type, ovate heart-shaped leaves that are entire or sometimes angled at the base, the underside covered with stalkless dendritic hairs and the upper side hairless. The inflorescence branches are conical, and the fruit is elliptical ovate. In North China it often sets very little fruit, but in the Yangtze River basin the fruit set increases markedly. It is distributed from the middle and lower reaches of the Yangtze River to the middle and lower reaches of the Yellow River.
5. Sichuan paulownia: The Sichuan paulownia has an umbrella-shaped or conical crown. The mature leaves are ovate heart-shaped, entire or slightly wavy, and the underside is yellow. The inflorescence branches are broadly conical, the flowers are purple or white, the base of the corolla suddenly enlarges into a bell shape, and the capsule is ovoid. It is distributed on the southern slope of Shennongjia in western Hubei, the Yichang area and western Hunan, as well as the mountainous areas of Sichuan, Guizhou and Yunnan, and is mostly wild.
6. Taiwan paulownia: The Taiwan paulownia has an umbrella-shaped crown, ovate or broadly ovate heart-shaped leaves, broadly conical inflorescence branches, cymes without a common peduncle, and ovoid capsules. The fruit shell is thin and shell-like. It is distributed in the southeastern provinces south of the Yangtze River, including Zhejiang, Fujian, Taiwan, China, Guangdong, Guangxi, Jiangxi and Hunan, and is also found in southwestern Hubei and southeastern Sichuan.
7. Tomentose paulownia: The tomentose paulownia has an umbrella-shaped crown, broadly ovate heart-shaped leaves, broadly conical inflorescence branches, cymes with a common peduncle nearly as long as the flower stalk, and ovoid fruit with a thin, shell-like shell. The tomentose paulownia is the most widely distributed species in the north, cultivated across a vast area from north of the middle and lower reaches of the Yangtze River to southern Liaoning, Beijing, Taiyuan and Tianshui, and has often been introduced south of the Yangtze River.
8. Smooth paulownia: The smooth paulownia is a plant of the genus Paulownia in the family Scrophulariaceae, a variety of the tomentose paulownia. Its main difference from the tomentose paulownia is that the underside of the mature leaves is hairless or has extremely sparse hairs, and the base is rounded to shallowly heart-shaped. It is distributed in Shaanxi, Gansu, Shanxi, Hebei, Henan, Shandong, Hubei and northern Sichuan, cultivated or wild, at elevations up to 1700 m.