Detailed Explanation of Key Points for High-Yield Cultivation Techniques of Polygonatum

Polygonatum, also known as Tiger Ginger, Chicken-Head Ginseng, Yellow Chicken Vegetable, Jointed Stem, etc. It is a perennial herb of the family Polygonataceae. Its underground rhizome is used as medicine, and it has the functions of tonifying the spleen and moistening the lungs, benefiting qi and nourishing yin. It mainly treats dry cough due to lung dryness, fatigue and weakness due to physical deficiency, palpitations and shortness of breath, dry mouth due to fluid depletion from prolonged illness, diabetes, hypertension, and other conditions. It is mainly produced in Shaanxi, Henan, Hubei, Sichuan, Guizhou and other provinces.

Morphological Characteristics

1. Polygonatum kingianum: A perennial herb. The rhizome is thick and fleshy, slightly block-like or nodular-swollen, 1-3 cm in diameter. The stem is 1-3 m tall, with the apex often twining. Leaves are whorled, sessile, usually 4-8 leaves per whorl, leaf blades linear to linear-lanceolate, apex acuminate and circinate. Flowers are axillary, pendulous, usually 2-4 in short cymes, with a membranous bracteole at the base of the pedicel; the perianth is tubular, usually pink, 18-25 mm in total length; stamens are inserted above the middle of the perianth tube; the style is 10-14 mm long, more than twice the length of the ovary. The berry is spherical, red when mature.

2. Polygonatum sibiricum: A perennial herb, 50-90 cm tall, occasionally reaching over 1 m. The rhizome is horizontal, cylindrical; due to nodular swelling, one end of each internode is thick and the other thin, with the thick end up to 2.5 cm in diameter; fleshy, pale yellow, the apex sometimes protruding like a chicken head. The stem is erect, slightly climbing in the upper part. Leaves are whorled, sessile, 4-6 per whorl, linear-lanceolate, apex acuminate and circinate. Flowers are axillary, pendulous, 2-4 in umbel-like clusters; the perianth is tubular, white to pale yellow, 9-13 mm in total length, with 6 lanceolate lobes; stamens are inserted above the middle of the perianth tube; the style is 1.5-2 times the length of the ovary. The berry is spherical, purple-black when mature.

3. Polygonatum cyrtonema: A perennial herb. The rhizome is horizontal, thick and fleshy, usually slightly nodular or moniliform, 1.2-2 cm in diameter. The stem is 40-100 cm tall, slightly leaning outward in the upper part, usually bearing 10-15 leaves. Leaves are alternate, sessile or nearly sessile; leaf blades elliptical to ovate-lanceolate; green above, grayish-green beneath, with 3-5 raised parallel veins. Flowers are axillary; the perianth is tubular, pale yellow to greenish-white, 18-25 mm in total length, with 6 triangular-ovate lobes at the apex; stamens 6; the ovary is nearly spherical; the berry is red or purplish-red when mature.

I. Growth Habits: Polygonatum prefers shaded and moist environments. It is cold-tolerant and afraid of drought. Soil requirements: deep soil layers, loose and fertile sandy loam rich in organic matter is best. Heavy clay, saline-alkali land, and low-lying land are not suitable for planting.

II. Land Preparation and Fertilization: Choose a field with high terrain and good drainage, and plow deeply and harrow thoroughly. In conjunction with land preparation, apply sufficient base fertilizer: 5000 kg of farmyard manure per mu, 20 kg of urea, 50 kg of phosphorus-potassium fertilizer, then make raised beds 1.5 m wide, ready for sowing.

III. Sowing: In Polygonatum production, rhizome propagation is used, and seed propagation can also be used. The sowing period is divided into spring sowing and autumn sowing. Spring sowing is around Qingming, and autumn sowing is around Lidong.

Rhizome propagation: Select robust, pest-free 1-2 year old rhizomes, cut into small sections, each with 2-3 nodes; after the wounds heal, plant them on the prepared bed surface at a row spacing of 30×15 cm. When planting, place the bud side up and lay flat in the hole. Water to preserve soil moisture and promote survival.

Seed propagation: Before sowing, stratify the seeds, that is, mix newly collected seeds with wet sand at a ratio of 1:3 and place them in a pit, insert a handful of wheat straw in the center to allow ventilation. Cover the top with a layer of wet sand. Carry out germination promotion. By the following spring, they can be sown. When sowing, first open shallow furrows on the prepared bed surface, then evenly scatter the seeds into the furrows. Cover with soil, water to preserve soil moisture, and promote seedling emergence. After the seedlings emerge uniformly, strengthen field management, and after 1 year of cultivation, they can be transplanted. When transplanting, plant them on the prepared bed surface at a row spacing of 25×20 cm, water to preserve soil moisture, and promote survival.

IV. Field Management: After Polygonatum seedlings emerge uniformly, pay attention to intertillage and weeding. In dry weather, pay attention to watering to keep the bed surface moist. In rainy weather, drain water promptly to prevent waterlogging and root rot. Because Polygonatum prefers shade, around Lixia, appropriately intercrop some tall-stemmed crops for shading. Around Liqiu, apply topdressing once: 10 kg of urea and 10 kg of potassium dihydrogen phosphate per mu. In winter, spread a layer of farmyard manure on the bed surface.

V. Pest and Disease Control: The main disease of Polygonatum is leaf spot, which can be prevented before onset with 1:1:100 Bordeaux mixture. In the early stage of onset, use carbendazim for control. For underground pests, use phoxim mixed with poisoned bait for trapping and killing.

VI. Harvest and Processing: Polygonatum propagated by rhizome requires 2-3 years, and Polygonatum propagated by seed requires 3-4 years before harvest. After the aboveground parts wither and turn yellow in late autumn, dig out the underground rhizomes, remove all soil, stems, leaves and fibrous roots. Wash clean and place in a steamer to steam for 10-20 minutes until thoroughly heated through, then sun-dry while kneading until completely dry, and it can be sold as medicine. The yield per mu is 300-500 kg.