When do pear trees bloom and what are the common grafting rootstocks?

The pear tree is a perennial deciduous fruit tree of the genus Pyrus in the Rosaceae family. It is a tree that is widely distributed around the world. The fruit of the pear tree is edible and has high nutritional and medicinal value. So, when do pear trees generally bloom? What are the common grafting rootstocks?

I. When do pear trees generally bloom?

Because pear trees have a wide distribution range, their phenological periods vary greatly. As far as the flowering period is concerned, in Huili, Sichuan, pear trees generally bloom in early to mid-February, while in Yanbian, Jilin, they bloom in mid-May; Yali pears bloom in early March in Changsha, Hunan, and in early May in Beizhen, Liaoning, with a difference of nearly two months in flowering periods among regions. For pear trees cultivated in the same area, phenological periods also differ depending on the species and variety. From bud break to flowering, varieties of the Ussurian pear group are the earliest, varieties of the white pear group are slightly later, varieties of the sand pear group are later than the white pear group, and European pear varieties are the latest, with a variation range of about 10 days.

II. What are the common grafting rootstocks?

(1) Pyrus betulifolia: widely wild in the provinces of North China and Northwest China. The root system of Pyrus betulifolia plants goes deep into the soil and is rich in fibrous roots. Seedlings grow vigorously and have strong cold resistance, drought resistance, waterlogging resistance, and salinity-alkali resistance. It is easy to graft with white pear and European pear, and young trees grow vigorously and bear fruit early and heavily. It is the main rootstock in northern China.

(2) Pyrus calleryana: wild in the provinces of North China and South China. The plant has strong adaptability and a deep root system, but poor cold resistance. It is suitable as a rootstock under warm and humid conditions and has strong compatibility with European pear. It is the main rootstock in southern China and is also widely used in Japan and Korea.

(3) Pyrus phaeocarpa: wild in the provinces of North China. In eastern Hebei, it is used as a rootstock; the tree is vigorous and bears fruit slightly late.

(4) Pyrus ussuriensis: most commonly wild in the three provinces of Northeast China. This species is the most cold-resistant of the genus Pyrus and can tolerate low temperatures and is relatively disease-resistant. Seedlings have many fibrous roots and vigorous branching; it is the main rootstock in Northeast China.

(5) Pyrus pyrifolia: Pyrus pyrifolia seedlings have well-developed root systems and good trunk development, and are resistant to heat and humidity; it is used as a rootstock south of the Yangtze River. The disadvantage is poor cold resistance.