2019 Toon Tree Planting Prospects and Cultivation Methods Explained

Toon is a nutritious vegetable grown on trees, and in many regions of our country there is the practice of picking tender toon shoots to stir-fry with eggs. So, what are the planting prospects for toon in 2019? What cultivation methods are there for the toon tree?

1. Analysis of toon planting prospects

Toon is a precious fast-growing tree species in our country used both for timber and as a vegetable. Because of its excellent wood quality, it is known internationally as “Chinese mahogany.” Toon leaves are thick and the shoots tender, with green leaves edged in red, like agate or jade, with a rich fragrance, and its nutritional richness far exceeds that of other vegetables. Although it is distributed across more than 20 provinces and cities in our country, quite a few provinces still lack toon resources. Toon is not only sold fresh on the market but can also be supplied year-round after simple processing, and its uses are even more varied and colorful. Thus since ancient times it has been a seasoning vegetable loved by the people of our country. In view of the current preference in large and medium-sized cities for natural green vegetables, large-scale production of toon sprouts, delivered to major guesthouses, restaurants, eateries and supermarkets, has good market prospects. In recent years the United States, Germany, Japan and Southeast Asian countries have shown a particular fondness for toon and have relatively large demand.

According to industry insiders, our country's future vegetable industry is transforming toward nutrition-oriented and health-care-oriented products. Toon sprouts, as a new type of vegetable that is famous, rare, special and both medicinal and edible, are highly favored by people. Therefore, toon sprouts grown out of season using protected facilities will become a hot-selling commodity, with very remarkable economic and social benefits.

2. Cultivation methods for the toon tree

1. Cultivation methods

① Ordinary cultivation. Toon propagation is divided into two types: sowing and raising seedlings, and division propagation (also called root sucker propagation).

Because toon seeds have a relatively low germination rate, before sowing, soak the seeds in warm water at 30—35°C for 24 hours, then remove them and place them at 25°C to sprout. Sow when the radicle is exposed to about the size of a grain of rice (the minimum ground temperature at sowing is about 5°C). In the Shanghai area this is generally in early to mid-March. After emergence, thin the seedlings when there are 2—3 true leaves, and set the final spacing when there are 4—5 true leaves, with a row-to-plant spacing of 25x15 cm.

For division propagation, in early spring dig up young seedlings from the roots of mature plants and plant them in a seedling bed; when the following year the seedlings have grown to about 2 m, transplant them into their final position. A root-cutting and tillering method can also be used: in late winter and early spring, dig a circular trench 60 cm deep around a mature tree, cut off some lateral roots, then fill the trench level again. Because toon roots readily produce adventitious roots, new shoots sprout from the cut root ends and can be transplanted the following year.

After toon seedlings have been raised, they are all planted out in early spring before bud break. For large-scale toon groves, the row-to-plant spacing is 7x5 m. When planted along canals or behind houses, they are in single rows, with a plant spacing of about 5 m. After planting, water 2—3 times to improve the survival rate.

② Dwarfing and close planting cultivation. This is a cultivation method developed in recent years. Its seedling-raising method is the same as ordinary cultivation; only the planting density and tree-form pruning differ. Generally about 6,000 plants are planted per 666.7 sq m. Tree forms can be divided into two types: the multi-layer type and the cluster type. For the multi-layer type, when the seedlings are 2 m tall, the terminal shoot is removed to encourage lateral buds to sprout, forming 3 layers of scaffold branches: the 1st layer 70 cm from the ground, the 2nd layer 60 cm from the 1st layer, and the 3rd layer 40 cm from the 2nd layer. This multi-layer type has a taller trunk, full lignification and relatively stable yield. For the cluster type, the terminal shoot is removed when the seedlings are about 1 m tall; for newly grown branches only the tender leaves are picked and the terminal bud is not removed; when the branches are 20—30 cm long, the tips are pinched off again. Its characteristic is a relatively short trunk and more main branches.

③ Protected cultivation. This can also be divided into two types: one is to cover dwarfed, close-planted toon grown in a greenhouse (or tunnel shed) with film in mid-November (referring to southern North China). The other is to heel in 2- to 3-year-old seedlings that have already passed dormancy inside a greenhouse (or tunnel shed). Keep the temperature inside the room (shed) at 18—24°C during the day and not lower than 12°C at night; after 40—45 days, the tender leaves can be harvested for eating.

2. Management

Although field management of toon is relatively extensive, in order to achieve fast growth and high yield, attention must still be paid to fertilizer, water and pest and disease control. If the weather is dry, water promptly; each year carry out intertillage and loosening of the soil, and it is best to interplant green manure between the rows, turning it under in May or applying human and livestock manure and urine.

Insect pests include toon caterpillars, cloud-spotted longhorn beetles and mealybugs, which can be controlled with pesticides such as Bacillus thuringiensis preparations; diseases include leaf rust and powdery mildew, which can be controlled with agents such as Bordeaux mixture and lime-sulfur mixture.

3. Harvesting

Toon under ordinary cultivation and dwarfed close planting cultivation generally sprouts before Qingming, and around Guyu the terminal buds can be picked. This first picking is called the first-round toon sprouts; they are not only plump and tender but also richly fragrant and of top quality. Afterward, according to growth conditions, the second picking is done 15—20 days later. Newly planted toon can be harvested at most 2 times; after 3 years it can be harvested 2—3 times each year, with yield increasing accordingly. As for protected cultivation, by applying heat it can also be harvested in winter; if not heated, it can supply tree sprouts ahead of time in early spring.