Key Points of Water Dropwort Cultivation Techniques and Detailed Field Management

Cultivation Season and Cultivation Methods Water dropwort is generally planted by arranging seedlings in batches from late August to late September, and harvested from early November to the end of March of the following year. It can be grown both in water and on dry land. Cultivation Techniques

1) Paddy field cultivation. After planting, irrigate so that the mother stems are half exposed above the water surface. Sprouting occurs in 7-10 days, then apply seedling fertilizer; after 15 days, drain the field to promote the development of stems, leaves and roots. After 30 days, when the seedlings are 12-15 cm tall, pull them up and replant them in the same place, with 3-4 plants per hole. Alternatively, when the seedlings are 30 cm tall, pull them up and replant them at a depth of about 18 cm to soften the stems and leaves. Seed-production fields must not be planted deeply, so as not to affect tillering. After heavy rain, drain promptly; in dry weather, irrigate late and drain early, and keep shallow water when applying topdressing. Stop topdressing after Frost's Descent, and gradually increase the water depth; the water depth should preferably be 6-9 cm below the leaf stalk fork, and must never exceed this fork. Before freezing, irrigate to protect against cold, with the water depth at most not exceeding the leaf tips. The harvest period of water dropwort lasts from October until bolting in early April of the following year.

2) Dry-land cultivation. ① Land preparation, making beds, and applying base fertilizer. It is better to plant water dropwort in soil or clay land with strong water- and fertilizer-retention capacity. In early August, apply 5000 kg of decomposed manure, 50 kg of superphosphate, and 1 kg of borax per 667 sq m as base fertilizer, turn the fertilizer into the soil, and then make beds. The bed surface is 1.3 m wide and 0.15 m deep. ② Planting. Divide the creeping stems into clumps of 3-4 plants and plant them at a plant spacing of 15 cm and a row spacing of 20 cm. Then cover with about 3 cm of soil, water thoroughly, and cover with a shade net or straw to keep warm. Water frequently before emergence to keep the ground moist. ③ Topdressing. Water dropwort has a relatively large fertilizer requirement, so topdressing should be combined with irrigation, 3 times in total, generally with fully decomposed organic fertilizer. The first topdressing is when the new seedlings have all emerged, applying 800 kg of 20% decomposed manure water per 667 sq m; the second topdressing is during the vigorous growth stage of the plants, with a concentration slightly higher than at the seedling stage. The third topdressing is mostly carried out in late October, when the plants have basically stopped increasing in height while the stems are filling out internally; this topdressing plays an important role in increasing yield and improving quality. ④ Earthing up for softening. From mid-to-late October, begin earthing up around the base of the plants so that they naturally enter the soil and are not bent over. The height of earthing up should preferably always leave 3-5 cm of the plant top exposed above the soil surface. Be sure to topdress once before earthing up. Make the part entering the soil soften and turn white, improving marketability. ⑤ Harvest. Generally, harvest and bring to market 25-30 days after earthing up. For those intended for spring harvest, apply less fertilizer before the end of the year, do not earth up, and after applying a heavy fertilizer once in February of the following year, earth up for softening. ⑥ Pest and disease control. During the growth period of water dropwort, the main problems are aphid damage and rot disease. For aphid control, spray with pesticides such as deltamethrin or Yibianjing; rot disease mainly occurs in the mid-to-late growth period under conditions of high temperature and humidity, overly dense plants, and poor ventilation and light transmission. It can be controlled with 1000-fold thiophanate methyl solution or 500-fold zineb solution; at the same time, strengthening field management and increasing potassium fertilizer application also help reduce the occurrence of the disease.