How to grow Pinellia ternata? Detailed cultivation techniques for Pinellia ternata (Part 1)
(1) Site selection and land preparation
Choose loose, fertile, neutral sandy loam soil with strong water and fertilizer retention capacity; it can also be intercropped under orchards or tall crops such as corn. Plow the soil in winter to let it weather and mature. In early spring, level the land, apply 30000 kg of barnyard manure or compost and 750 kg of superphosphate per hectare, then rake fine and level to make high beds 1.3 m wide with furrow width of 40 cm.
(2) Propagation: Generally, tuber or bulb propagation is the main method; seed propagation is also possible, but the seed germination rate is low and the production cycle is long, so it is rarely used.
1. Tuber propagation: When digging Pinellia ternata in autumn, select small tubers 1-1.5 cm in diameter that are robust and free from pests and diseases for seed use. Mix with fine sandy soil, place in a ventilated and shaded area, and take them out for planting in the same winter or the following spring. Spring planting is preferable; autumn and winter planting yields low output. Before planting, grade the tubers by size and plant them separately. Generally, sow when the average daily ground temperature in spring is about 10°C, with row spacing of 12-15 cm and plant spacing of 5-10 cm, open furrows 10 cm wide and about 5 cm deep, arrange the tubers in staggered rows within each furrow with buds facing upward. Cover with soil and level, press down slightly; generally about 1500 kg of seed tubers per hectare is used. To facilitate earthing up and weeding, double-row strip sowing can also be used, that is, wide rows of 30 cm and narrow rows of 10 cm. Autumn planting method is the same as spring sowing.
2. Bulb propagation: Each stem and leaf of Pinellia ternata grows one bulb, with sufficient quantity, high germination rate and early maturity, and it is currently the main propagation route for developing Pinellia ternata production. In summer and autumn, when the old leaves are about to wither, the bulbs are already mature and can be harvested for propagation. Dig holes at row and plant spacing of 10 cm × 8 cm, plant 2-3 bulbs per hole, then cover with 1-1.5 cm of soil and press slightly. For bulbs that fall on the soil surface, the "soil covering method" can be used for cultivation. The method is: each time a batch of seedlings falls, cover with soil once; the soil covering should be thin, just enough not to expose the bulbs. At the same time, apply an appropriate amount of phosphorus and potassium fertilizer, which can both ensure bulb growth and promote the enlargement of the underground mother tuber, achieving two goals at once and favoring increased yield.
3. Seed propagation: Pinellia ternata over 2 years old can bloom and bear fruit successively from early summer to autumn and winter. When the spathe turns yellow and droops, collect the seeds and store them in wet sand. From late March to early April, choose a semi-sunny and semi-shady plot, prepare the land and make beds, open shallow furrows for drilling at row spacing of 5-7 cm, cover with 1 cm thick fine soil after sowing, and cover with grass to keep warm and moist; seedlings emerge in about 15 days. After emergence, remove the covering grass in time; when the seedlings are 6-9 cm tall, they can be transplanted.
(3) Water and fertilizer management: Regardless of which propagation method is used, water thoroughly once before sowing to facilitate emergence. After emergence, water frequently as well; especially around "Beginning of Autumn" when water demand is high, use 1:10 manure water for sprinkling irrigation to keep the soil moist regularly. After autumn, gradually reduce the amount of watering. In addition to applying sufficient base fertilizer, topdress 4 times during the growing period. The first time is after full emergence in early April, apply 15000 kg of 1:3 human and livestock manure water per hectare; the second time is during bulb formation in late May, apply 30000 kg of human and livestock manure water per hectare; the third time is after the seedlings fall in August, when the daughter Pinellia ternata exposes new buds and the mother Pinellia ternata sheds its shell and grows new roots again, sprinkle with 1:10 manure water once every 15 days until seedlings gradually emerge after autumn; the fourth time is in early September, when all Pinellia ternata seedlings are full, apply 375 kg of decomposed cake fertilizer, 300 kg of superphosphate and 150 kg of urea per hectare, mix evenly with ditch mud, and spread on the soil surface, which serves to earth up and is beneficial for grain filling.
(4) Field management
1. Intertillage and weeding: Pinellia ternata plants are short, so during the growing period, loosen the soil and weed frequently, achieving early and small weed removal to avoid weed infestation; the depth of intertillage generally should not exceed 5 cm to avoid damaging the roots.
2. Removing flower stems: If seeds are not to be kept, cut off the flower stems when they bolt in May, so that nutrients are concentrated on underground tuber growth, which is beneficial for increasing yield.
3. Drainage and irrigation: Pinellia ternata likes moisture and fears drought; when there is a long period of clear weather without rain, irrigate in time; if there is too much rain, drain in time to avoid tuber rot caused by water accumulation in the field.