How to cultivate the Chinese medicinal herb fuzi? A detailed explanation of planting techniques
Site selection and land preparation
For cultivating wutou (Aconitum carmichaelii), it is best to choose sun-facing, well-drained cultivated land or virgin land. Purple soil, sandy loam, and yellow clay soil are best. Avoid land whose previous crop was a legume, a solanaceous plant, or Atractylodes macrocephala, Rehmannia glutinosa, Scrophularia ningpoensis, etc. Land that has been under rotation for less than 6 years should undergo soil disinfection.
After selecting the site, clear the weeds and plow as usual. For land that needs disinfection, use 2.5 kg of 50% thiram per mu, mix with 3.5 kg of plant ash, spread on the soil surface, then plow 3 times and harrow 3 times, and make raised beds 1 m wide. Use 2500 kg of plant ash and 75 kg of oil cake per mu, mix well, and turn into the bed surface. Alternatively, at planting time, use 1200-1600 kg of human and livestock manure water per mu to soak the holes, and add a small pinch of superphosphate per hole, at 20 kg per mu.
For planting fuzi, choose purple-red mud, oil sand soil, white soil, sandy soil, or yellow clay soil with deep, loose, fertile, well-drained soil. Purple-red mud and oil sand soil are best. Avoid continuous cropping. Rice and corn are used as the preceding crops in rotation. Generally, it is best to choose paddy fields that have not grown fuzi within 3 years. After the rice harvest, drain the field water to allow full weathering and increase fertility. Starting from Major Snow, plow and harrow several times to make the soil fine, even, loose, and level. After land preparation, use a rope to “tread the beds.” Tread them into beds with a furrow width of 27 cm and a bed surface width of about 66 cm or 73 cm. The purpose of treading the beds is to make the soil at the bed edges firm, so as to prevent the beds from collapsing after trenching and during the growing period. After treading the beds, spread fully decomposed compost (per mu, use 4000 kg of pig and cattle pen manure, 50 kg of superphosphate, and 50-100 kg of oil cake, mix thoroughly and finely, and pile and compost for about 7 days) on the bed surface, hoe it into the soil, and mix fully with the soil, then shape the bed surface into a turtle-back form, ready for planting.
Planting methods
1. Seedling and seed root cultivation: For cultivating fuzi, wutou is used as the seed stock (called wuyao in Sichuan production areas). Wutou can be propagated sexually or asexually. Wild wutou mainly relies on sexual reproduction, while cultivated wutou mostly uses asexual reproduction.
(1) Seed selection: There are many varieties of wutou. After identification and screening, the following 3 varieties with strong stress resistance, high yield, and good quality have been retained:
Nangua Ye: Also known as Ezhang Ye. The top leaves resemble pumpkin leaves, the tuberous roots are relatively large and conical, with a high processing rate, tolerance to fertilizer, late maturity, and high yield. However, its disease resistance is relatively poor. Under comprehensive control of southern blight, its yield is relatively stable. Its average wutou yield per plant is 6.5, with an average yield of 42,000 per mu, and the planted fuzi averages 490 kg of mud fuzi per mu. In extension demonstrations, Nangua Ye wutou increased yield by 23.6-55.2% compared with local mixed populations, and it is currently the mainstream seed in production areas.
Mei Ye Zi: The stem is thick and strong, with relatively dense nodes; the basal leaves are blue-green; the stem leaves are large, dark green, thinly leathery, 3-parted, with large gaps between the parted segments, and the ultimate lobes are linear-lanceolate; the tuberous roots are spindle-shaped; the average wutou yield per plant is 6.3, with an average yield of 52,000 per mu, and the planted fuzi averages 456.6 kg per mu. Its disease resistance is stronger than that of Nangua Ye, and its yield is relatively high and stable.
Hua Ye Zi: Also known as Ai Ye Zi. The top leaves extend upward, the leaves are thick and firmly papery, the leaf surface is yellow-green and lusterless, the veins are prominent and rough, the leaves are 3-parted, the base is truncate or wedge-shaped, the deep lobes are further deeply lobed, and the ultimate lobes are lanceolate-elliptic. The tuberous roots are conical; the average wutou yield per plant is 3.2, with an average yield of 27,700 per mu, and the planted fuzi averages 368.3 kg per mu. Although the yield is lower, it is more disease-resistant.
When harvesting and digging wutou, cut off the excessively long fibrous roots, leaving about 1.5 cm, and remove scorched, water-soaked, and bud-deficient seed roots, then grade them into 3 grades by size: large, medium, and small. The largest grade 1 and smallest grade 3 tuberous roots are kept in mountainous areas as wutou seed stock, while the medium-sized grade 2 is transported to dam areas as fuzi seed stock. The tuberous roots used as wutou seed stock can be planted immediately, or spread briefly indoors before planting.
(2) Planting: In Sichuan, it is done in mid-December; in Shaanxi, in early November. Before planting, use 0.5 kg of 50% thiram and 0.5 kg of urea, dilute in 250 kg of water, and soak the seed roots for 3 hours. Plant in holes. For grade 1 seed roots, the row spacing is 17 cm each, hole depth 12-15 cm, 3 rows per bed in staggered arrangement, 1 planted per hole, 12,760 per mu; for grade 3 seed roots, the row and plant spacing is 13 cm each, hole depth 7-10 cm, 4 rows per bed, 1 planted per hole, 20,000 per mu. When planting, plant 10-15% more seed roots between rows for use in replanting. After planting, cover with soil and level the bed.
(3) Harvesting, storage, and transport of wutou: Wutou is harvested after the Start of Winter in the second year of planting. Cut off the excessively long fibrous roots, pack by grade in bamboo baskets, and promptly transport to dam areas for planting. It should not be stored for long, to avoid rotting. During transport, it must not be exposed to sun or rain, and must be protected from heating and mildew. If it cannot be planted promptly after arriving in dam areas within 1-2 days, it should be spread in a cool, dry place lined with straw, about 4.5 cm thick, and turned frequently to prevent heating. Storage time should not exceed 7 days.
2. Fuzi planting: In Sichuan, it is done from Major Snow to Winter Solstice, and planting 6-10 days before the Winter Solstice is preferable, as the seedlings develop neatly and robustly, the tuberous roots grow quickly, the heads are large, and the yield is high. In Shaanxi, it is planted after the Start of Winter. At planting time, in the middle of the prepared bed surface, use a wooden marking rake to open staggered holes: 2 rows for a 66 cm-wide bed, 3 rows for a 73 cm-wide bed, with row and plant spacing of 17 cm each. Then plant the seed roots separately according to large, medium, and small sizes. Plant 1 large and 1 medium tuberous root per hole, and 2 small roots. The bud opening should face upward and be slightly exposed above the bed surface, then use hands to draw soil to stabilize the seed roots. Every 10 holes, plant 1-2 extra outside the holes for use in replanting. For single-plant two-row planting, plant 0.85-10,000 per mu. For double-plant two-row or 3-row-per-bed planting, plant more than 12,000 per mu. After planting, move soil from the bed furrows onto the bed surface to cover the seed roots, about 7 cm thick, with furrows 20-24 cm deep and about 27 cm wide. The bed furrows should be level and unobstructed to prevent water accumulation.
Field management
1. Management of seed root fields
In early spring, apply 1000 kg of clear manure water per mu, or irrigate with mixed furrow water, to promote emergence. After emergence, promptly remove plants with downy mildew, take wutou seedlings from between rows for replanting, and apply clear manure water to help them survive. Before stem elongation, apply 1000-1500 kg of human and livestock manure water per mu or 10 kg of urea to promote seedling growth. In early May, weed and combine with topdressing, applying 1000-1500 kg of human and livestock manure water per mu, and clean the bed furrows and earth up. When the seedlings are 1 m tall, keep 11-12 basal leaves, remove the tip of the terminal bud, and then remove the axillary buds at the 1st-2nd nodes. After bud removal, combine with weeding and apply 25 kg of superphosphate plus 1500 kg of decomposed compost per mu, then earth up after application.
In early April, sow corn on the bed surface at 40 cm plant spacing, leaving 2-3 seedlings per hole to provide shade. From May to August, attention should be paid to controlling southern blight.
2. Management of fuzi planting fields
(1) Raking the beds, clearing furrows, and replanting: Before the seedlings emerge, use a bamboo rake or a two-toothed wire hook to scrape large soil clods and excessively thick covering soil from the bed surface into the furrows, chop them up, then earth them back onto the bed surface, and level the furrow bottom, keeping it flat and free of water accumulation. Do not rake the beds too deep, so as not to injure the seed buds. After the seedlings have all emerged, if diseased plants are found, immediately pull them up and burn them. Replanting should be done early rather than late.