Detailed Explanation of Key Technical Points for Growing Toon (Chinese Mahogany) in Greenhouses
Toon, also known as toon sprouts or toon seeds, is the tender bud of the toon tree. It is not only delicious but also very high in nutritional value, making it a much-loved home-style dish among consumers. Because toon is seasonal and can only be eaten in spring, the market supply falls short of demand, so growing toon in greenhouses has become one of the most popular planting industries.
Greenhouse Toon Planting Techniques
Toon sprouts are a woody vegetable with high nutritional value. Toon can be propagated by seed, or by division or cuttings. Toon is mostly grown in the open field, and the most widely used method is the dwarfed close-planting technique, which allows either direct sowing or raising seedlings for transplanting. The row spacing is 50cm and the plant spacing is 10-15cm. It can also be planted in clumps, with a row spacing of 200cm, a clump spacing of 100cm, and 3-5 plants per hole. When the seedlings reach nearly 200cm in height, the top shoot is removed so that lateral branches sprout to form three tiers of scaffold branches, with the spacing between each tier being about 40, 60 and 70cm respectively. This method gives stable yields and strong cold and drought resistance. To improve planting returns, toon can be grown under protected cultivation. Protected cultivation requires dwarfing and shaping of the plants.
A reasonable planting density per mu is 2000-6000 plants. For plants of the current year, when the seedlings grow to 4-6 true leaves in early May, they can be transplanted according to the wide-narrow row system, with a wide row of 80cm, a narrow row of 50cm, and a plant spacing of 16-50cm. In early July, when the seedlings reach 40-50cm in height, the growing tips are pinched off to promote dwarfed cultivation, and pinching is done again in mid-August. The exact timing of pinching for each individual plant must be handled flexibly. For plants more than two years old, the top dominance can be broken by stumping to promote the development of branches and achieve dwarfing. Generally, stumping in late June is suitable, which can achieve the effect of dwarfing, clumping, multiple branches and plump terminal buds. Toon is suitable for growing in neutral or weakly alkaline soil. Toon is a tree species that likes moisture but dislikes waterlogging, so standing water should be drained promptly after rain.
Key Points for Growing Toon in Greenhouses
1. Land preparation. Choose a deep, fertile sandy loam plot with irrigation conditions, facing the sun and sheltered from the wind. Plough about 50cm deep, apply 4000 kg of farmyard manure per 1/15 hectare (1 mu), water thoroughly, and make beds 1m wide and as long as the greenhouse is wide.
Planting. Plant about 3000 plants per 1/15 hectare, and choose sturdy seedlings about 0.5m tall with multiple terminal buds. Covering the greenhouse. It is best to cover the greenhouse from late November to early December. The size of the greenhouse depends on the area. Build an arched frame running east-west, 2-2.5m high, and cover it with straw mats at night for insulation. Water once before covering the greenhouse.
2. Management. At around 10 a.m. during the day, uncover the straw mats so that sunlight shines into the greenhouse, and the temperature inside can rise to about 20°C. At night, cover with straw mats to prevent heat loss and keep the temperature above 0°C. Generally, after about 50 days, the toon begins to sprout, and around the Spring Festival it can grow to about 20cm. The economic returns are very considerable.
Field Management
1. Fertilizer and water
After the plants are established, apply fertilizer and water promptly, and combine this with cultivating and weeding to promote rapid growth of the seedlings.
2. Pest and disease control
Toon pests include toon caterpillars, slug moths and cloud-banded longhorn beetles. During the larval stage, they can be sprayed with 800 times diluted trichlorfon solution, and during the adult stage, they can be controlled with 1500 times diluted dimethoate. Diseases include leaf rust and powdery mildew, which can be controlled with 500 times diluted triadimefon. Clean the field in winter to reduce the overwintering population of pests and diseases.
3. Pruning
Each year after the spring harvest of toon sprouts is finished, from mid-to-late June to early July, prune the main trunk (behead it) at a height of 20cm above the ground to encourage lateral buds to sprout into new branches. From late July to early August, pinch the tips according to the vigor of the new branches; those with strong growth can be tip-pinched earlier, and conversely, tip-pinching can be delayed, combined with fertilizer and water management, to promote the formation of plump terminal buds. The growth period of toon sprouts is short, so they should be eaten early, fresh and tender. There is a saying: "Toon sprouts before the rain are as tender as silk; toon sprouts after the rain are like wood." The harvest standard is preferably purple-red buds with a bud length of 10-15cm. When harvesting, pick the terminal buds first and then the lateral buds; if the terminal buds are not harvested, the lower lateral buds will be difficult to grow or will grow poorly. When picking the buds, gently snap them off by hand at the base of the leaf stalk, tie them into small bundles of 100-200 grams, put them in plastic bags and seal them to prevent water loss and wilting, improving their market quality. Each year, toon sprouts can be harvested 3-4 times, with a yield of 400-500 kg.
Processing, Pickling and Storage
After processing and pickling, toon sprouts can be stored for a long time and transported at any time. The method is simple and easy. Wash the freshly harvested toon sprouts with water, dry them in the shade, then add 20 kg of salt per 100 kg. In the jar, put a layer of toon sprouts and a layer of salt, with less salt in the lower layers and more in the upper layers. After 3-4 hours, turn the contents of the jar, and after another 5-6 hours, turn them a second time, turning a total of 5-6 times. After about 20-30 days, they are properly pickled. Take them out, spread them out to dry in the shade for 1-2 days, add a small amount of rice vinegar to increase gloss and crispness, then sun-dry until 50-60% dry, tie into small bundles of 100-150 grams, put them into a small-mouthed jar, arrange them tightly and press them firmly, seal the opening for storage, and they can be kept for 2-3 years.
Through the above content, I believe everyone now has a deeper understanding of growing toon in greenhouses. Toon is a very delicious and nutritious ingredient, and its preparation is both simple and quick. Because toon is seasonal, the time to enjoy it is very short, but growing toon in greenhouses easily solves this problem, and the yield is high, showing that toon cultivation has broad prospects.