How Tall Can a Longan Tree Grow? Detailed Explanation of Flowering, Fruiting Time and Lifespan

Longan, also known as guiyuan, yizhi, or sanchi nongwei, is an evergreen tree. The longan tree usually grows to over 10 m, with occasional large trees reaching up to 40 m in height and 1 m in trunk diameter, featuring buttress roots. Its flowering period is between spring and summer, and its fruiting period is in summer. Longan is rich in glucose, sucrose and protein, and also has a relatively high iron content, which can boost energy and supplement nutrition.

1. How long does it take for a longan tree to flower and fruit?

After the longan is planted, following 3-4 years of proper cultivation and management, it has basically formed a canopy that fruits early and yields well, along with a well-developed root system, and has acquired the nutrient conditions for flowering and fruiting, beginning to enter the young fruiting stage.

2. How long can a longan tree live?

According to Mr. Zhang, a grower in Fujian, a longan tree generally lives for several decades; if a fruit farmer plants one, it is no longer wanted once the peak fruiting age has passed. In Chengtian Temple in Quanzhou, Fujian, there is an ancient longan tree over 200 years old, which is the oldest surviving 'Dongbi' longan tree. Today, the 'Dongbi' longan has been widely propagated in Quanzhou and other longan-producing areas of the province.

3. How do longan trees get through the winter?

In winter, as temperatures gradually drop, the longan tree needs to enter a relative dormancy during the overwintering period, with vegetative growth temporarily slowing and stopping, accumulating sufficient organic nutrients, and endogenous hormone activity promoting the onset of physiological flower bud differentiation. This is an important part of achieving early fruiting and high yields the following year. Therefore, winter management of the longan orchard should be taken seriously. The main technical management measures to be adopted are as follows:

(1) Strengthen the renovation of low-yielding orchards in winter. Winter is a good time to renovate low-yielding longan orchards. Winter idle labor can be used to carry out basic orchard construction, repair orchard terrace walls and embankments, clear drainage and irrigation ditches, and build water conservancy and soil and water conservation projects. Do a good job of expanding planting holes, applying slow-release farmyard manure to improve the soil or bringing in soil to build up the soil, so as to raise soil fertility.

(2) Carry out winter orchard cleaning. In winter, low temperatures leave pests and diseases in an inactive, weakened state. Therefore, advantage should be taken of this to do a good job of cleaning the orchard, pruning off diseased and pest-infested branches, crossing branches, shaded branches and dead branches from the longan trees, and gathering them for burning.

(3) Control winter shoots of the longan. In recent years, due to climate warming, the phenomenon of warm winters has appeared, triggering the sprouting of winter shoots on longan, which consumes the nutrient components of the longan tree and is unfavorable for flower bud differentiation.

The methods for controlling the sprouting of winter shoots are as follows:

1. Deep plowing to cut roots and air-dry the roots. For trees with relatively vigorous growth, deeply plow the root zone (deep plowing 20 cm) or dig a deep trench 30-50 cm deep around the outer edge of the canopy to cut off part of the root system, sun-dry for 2-3 weeks, then fill in soil and miscellaneous fertilizer to promote flower bud differentiation. However, for old and weak trees, too much root damage should be avoided.

2. Remove winter shoots. For winter shoots that have already sprouted, they can be removed manually or knocked down with a bamboo pole.

3. Chemical shoot control.

(4) Cold and frost protection for longan trees in winter. Longan trees like warmth and dislike freezing. In normal years, longan in our city can overwinter safely, but in certain years, when cold waves strike, longan orchards in low-lying areas and coastal sandy land can suffer frost damage, especially young trees, which should be a cause for vigilance. Cold and frost protection methods: build up soil at the base of the tree, whitewash the trunk, wrap and cover the canopy with rice straw and plastic film, apply heat-generating fertilizers such as burnt soil to make the plants robust and increase their cold resistance, and adopt irrigation, water spraying, smoke fumigation and other frost protection measures before frost arrives.