Detailed Explanation of the Latest Cultivation and Management Techniques for Ostericum sieboldii
I. Open-field Cultivation
1. Land preparation. Choose flat, well-drained sandy loam soil with a deep, moist layer and high organic matter content. Apply 30000-45000 kg of base fertilizer per hectare and 225 kg of NPK compound fertilizer. Plow 20-30 cm deep, harrow level, and make flat beds 10-15 m long and 1 m wide.
2. Sowing. In late March, soak Ostericum sieboldii seeds in 40 mg/kg gibberellin for 2 hours or in water for 4 hours before sowing. In the beds, open shallow furrows 2-3 cm deep at a row spacing of 20-25 cm, and scatter the seeds evenly. The seeding rate is 60-75 kg per hectare. After sowing, rake the bed surface level and press it gently with a wooden board. Seedlings emerge in 15-20 days.
3. Seedling raising. After the seedlings emerge, loosen the soil and weed. From April to May, water once every 15-20 days. When the seedlings are 5-7 cm tall, carry out the first thinning; when they are 8-10 cm tall, finalize the spacing, keeping 500 plants per sq m. After final thinning, spray 0.3% urea plus 0.2% monopotassium phosphate solution twice at 7-10 day intervals. Pay attention to drainage during the rainy season, and loosen the soil and weed promptly after rain to improve soil aeration. From July to August, spray 0.3% monopotassium phosphate solution 2-3 times to improve the winter hardiness of one-year-old seedlings.
4. Transplanting. Ostericum sieboldii is best transplanted in autumn. After land preparation, fertilization, and ridging, plant with two rows per ridge and a plant spacing of 6-10 cm. Water thoroughly after planting, then water appropriately according to soil moisture. Cover the soil 3-4 cm above the growing point of the seedlings, and cover the ridge surface with 1-2 cm of rice straw or similar mulch to aid overwintering.
5. Field management. After transplanting, water and weed promptly. If there are missing plants, fill them in. 15-20 days after the seedlings recover from transplanting, apply a nitrogen fertilizer once to promote seedling growth. Fertilizer and water management in spring is the key to Ostericum sieboldii cultivation. After the soil thaws, remove dead leaves and dried plants from the field. Apply 300-450 kg of urea per hectare. In early spring, when soil temperature is relatively low, the first irrigation should be carried out when the plants are 10-12 cm tall, and water once every 7-10 days. Once the harvest period begins, apply quick-acting nitrogen fertilizer promptly. In the middle and late stages of growth, timely intertillage, weeding, and supplementary application of phosphorus and potassium fertilizers should be carried out.
6. Harvesting. When the plants are more than 30 cm tall, the leaf color begins to darken, and the broken petioles have a small amount of fiber but are still crisp and tender, they can be harvested. When harvesting, grasp the base of the petiole by hand and snap it outward, taking care not to damage the small leaflets and growing point. Tie into bundles for market.
7. Seed collection and treatment. In mid-to-late September, the seeds mature successively; harvest them in batches. After harvesting, spread them flat on a reed mat, dry them in the shade, remove all impurities, and put them into gauze bags. In mid-to-late October, stratify the harvested seeds in sand. Choose high ground that is well-drained and has good air permeability, and dig a sand storage trench 30-35 cm deep, with length and width determined by the amount of seed. Soak the seeds in clean water for 12 hours, remove them, and mix with 3-5 times their volume of moist sand, until the mixture holds together in a ball when squeezed but does not drip. After mixing evenly, place it in the trench and cover with soil 10-15 cm above ground level. Every 15-20 days, remove the covering soil and turn the seeds over once, until the ground freezes.
II. Protected Cultivation
In early March, begin covering with an arched shed. First insert shed ribs on both sides of the bed surface to form an arched shed, cover with plastic film, and seal both sides tightly with soil. In 15-20 days, Ostericum sieboldii grows to about 10 cm. On sunny days at noon, pay attention to ventilating the arched shed to avoid excessively high temperatures inside that could cause scorching. It can be marketed in early April, yielding 1 kg of fresh Ostericum sieboldii per sq m. After removing the film, do not harvest the Ostericum sieboldii that sprouts a second time that year, so as to ensure good underground growth and promote robust growth the following year. When the plants grow to 10-15 cm, apply ammonium nitrate once, at 1.5 kg per 666.7 sq m. Strengthen field management to prevent weed overgrowth and drought.