Detailed Explanation of Key Points for High-Yield Cultivation Techniques of Solomon's Seal
I.Solomon's SealThe seeds are of the epicotyl dormancy type. The after-ripening period of the embryo requires a temperature of around 25°C, and the epicotyl needs a low-temperature stage to break dormancy. After sowing, in the first summer only roots grow and no seedlings emerge, and seedlings do not appear until April of the following year.
The rhizome of Solomon's seal survives for 3 or 4 years; beyond this time it will rot. Solomon's seal planted in autumn sprouts in March to April of the following year. From sprouting to seedling emergence, growth is relatively slow and the stems are weak. From May to June, as temperatures gradually rise, stems and leaves grow rapidly and can produce buds and flowers. In the high-temperature season of July, aboveground growth slows down while rhizome growth accelerates. In the 2nd year after planting, the plants grow weakly and have poor adaptability to the environment, unable to withstand direct sunlight during the high-temperature season. In the 3rd year, the plants grow taller, the stems increase in size, the rhizomes develop faster and growth vigor is stronger. In the 4th year, the aboveground stems increase in number and grow very rapidly, canopy density increases, and the rhizomes crisscross underground.
II. Cultivation Techniques
1. Site selection and land preparation. Solomon's seal is cold-resistant, tolerant of shade and moisture, and averse to direct strong light and wind. It prefers a shady, moist and cool climate. The planting site should be chosen as a wind-sheltered, sunny location with good drainage, fertile and loose soil, and deep sandy loam. It should not be cultivated on heavy clay, barren, low-lying, waterlogged land. Continuous cropping should be avoided to prevent pests and diseases. The previous crop is best a leguminous plant. After selecting the site, first apply organic fertilizer as base fertilizer at 2500 kg to 3000 kg per mu, spread it evenly on the ground, deep-plow the soil 30 cm, harrow finely and make beds 1.0-1.30 m wide, with ditches 25-30 cm wide and 15 cm deep. Remove all weeds and let the beds be exposed to the hot sun.
2. Planting method. Solomon's seal is propagated by seeds and rhizomes, and propagation is very fast. Rhizome propagation is currently used in production because its heredity is more stable than that of seeds, it can ensure high yield, and its growth cycle is short. At harvest time, select from plants with thick stems the plump rhizomes that are free of pests, black spots, pitting, and damage, yellow-white in color, with full terminal buds, many fibrous roots, neat bud ends, and slightly concave inward, to use as seed material. Branches that are thin and small, and old branches with sharp, outward-protruding bud ends, cannot sprout and are not suitable for seed retention; otherwise, with insufficient nutrition and weak vitality, they affect the offspring, resulting in poor quality and low yield. The main stem is also not suitable for seed retention; because the main stem is large and long, the cost is too high, and removing the main stem seriously affects quality, making it difficult to sell. It should be dug, selected and planted promptly. If weather changes prevent timely planting, the root buds must be spread out indoors in a wind-sheltered, cool place. Generally, 200-300 kg of seed rhizomes are used per 667 sq m. Soak the selected seed rhizomes in a bucket containing 500-fold dilution of 50% carbendazim; the solution should submerge the seed rhizomes. After soaking for 30 minutes, remove and air-dry for later use.
Planting is generally carried out from July to November. Hole planting or furrow planting. Hole planting: plant 3-4 rows per bed, with row spacing of 30-40 cm, plant spacing of 30-40 cm, and hole depth of 8-10 cm. Place 3-4 seed sets crossed in each hole, with buds facing outward in all directions, not in the same direction. Furrow planting: open furrows 6-15 cm deep on the bed surface at row spacing of 15-30 cm. When planting, cut the Solomon's seal rhizomes into small sections about 3-7 cm long, arrange them longitudinally at the bottom of the furrow at plant spacing of 7-17 cm, with buds facing the same direction, and cover with pig manure or farmyard manure. The amount of rhizomes used is 250-300 kg per mu.
3. Field management
No seedlings emerge in the year after planting. After emergence in the following spring, weeds in the field should be removed promptly. When the soil is dry, pull them by hand; never use a hoe, to avoid injuring the rhizomes and causing rot. Weeding is not suitable after rain or when the soil is too wet. Thereafter, weed once each in May and July. In the 3rd year, only hand-pulling of weeds is suitable.
Apply sufficient base fertilizer. In combination with land preparation, apply 2000-3000 kg of decomposed farmyard manure per 667 sq m. After covering the seed sets with soil, apply 200 kg of charred mud ash or 30-35 kg of compound fertilizer per mu beside the holes. Fertilization is carried out before sprouting in spring to promote stem and leaf growth. When the seedlings are 7-10 cm tall, apply 800-1000 kg of dilute human and animal urine or 10 kg of urea per 667 sq m. Fertilize when Solomon's seal enters dormancy, applying decomposed pig manure and phosphate fertilizer, then cover with soil 5-7 cm thick. After 2 years of growth, the rhizomes branch profusely, crisscross, and are prone to being exposed on the soil surface and turning green, affecting the appearance and quality of the product and making them susceptible to freezing damage, so soil should be earthed up in a timely manner.
Solomon's seal is most averse to waterlogging. Before the rainy season arrives, the ditches should be cleared to facilitate drainage.
Earthing up. Each winter, in combination with fertilization, take soil from the furrows to earth up 3.0-4.5 cm, and cover the Solomon's seal seed sets with rice straw, leaves or thatch. Thereafter, in early winter each year, when the stems and leaves of Solomon's seal wither, cover with green grass and then a layer of soil on top.
4. Pest and disease control
(1) Diseases. Leaf spot: brown round lesions appear on the leaf surface with purplish-red edges, often occurring in summer and autumn. Control method: before onset or in the early stage of the disease, spray 1:1:120 Bordeaux mixture or 800-fold dilution of 50% amobam, once every 10 days, 2-3 times consecutively. Rust: yellow round lesions appear on the leaf surface, with yellow ring-like small granules on the underside. Control method: promptly remove and burn diseased plants, and spread quicklime in the holes for disinfection. Root rot: when the disease occurs, the rhizomes rot, ultimately causing plant death. Control method: do a good job of drainage, reduce soil moisture, and control the spread of the disease.
(2) Insect pests. Mainly brown scarab beetles, black scarab beetles, red-legged green scarab beetles, etc., which mainly damage the roots. Control method: apply fully decomposed organic fertilizer as base fertilizer or topdressing; make poisoned bait from rice or wheat bran and scatter it on the bed surface in the evening to trap and kill; when pest infestation is severe, pour 1000-fold dilution of 90% trichlorfon onto the roots.
5. Harvesting and processing
(1) Harvesting. Harvest is generally carried out in the 3rd year after planting. In the south, harvest in autumn; in the north, harvest in spring, so as to connect with the planting time. After the aboveground parts wither, harvest before the plants sprout in spring, choosing a sunny day when the soil is relatively dry. When digging, first cut off the aboveground stems, dig up the rhizomes, shake off the soil, and prevent breakage. The rhizomes retained for seed are piled separately.
(2) Processing. Sort the dug rhizomes by length, shortness, thickness and thinness into grades, and dry them separately. At night, after the Solomon's seal has cooled thoroughly, add a cover. Never bag Solomon's seal that has not cooled thoroughly, to avoid heating and deterioration. Generally after drying for 2-3 days, the rhizomes of Solomon's seal become very soft and not easy to break. Then remove the fibrous roots and mud and sand, and rub and knead the rhizomes on a stone slab or wooden board. When rubbing and kneading, start slowly and then speed up, from light to heavy, until the coarse skin is completely removed, the Solomon's seal rhizomes have no hard core, are golden yellow and semi-transparent, and sugar juice exudes when pressed by hand; then dry in the sun and it is done. In Northeast China, the processing method for wild Solomon's seal is rubbing first and then drying, repeated 3-4 times until dry. Some people also use a combined steaming and rubbing processing method, that is, first dry fresh Solomon's seal in the sun until soft, then steam for 10 minutes, use high temperature to promote sweating so that sugar juice exudes, then pack it in an airtight plastic bag, and after about 30 minutes, rub by hand or tread on the whole package with feet until the Solomon's seal turns yellow and semi-transparent, then take it out and spread it in the sun to dry. During processing, avoid excessive rubbing and kneading, otherwise the color will darken or even turn black, affecting commodity quality.