How to Grow Polygonatum kingianum? A Detailed Guide to Key Cultivation Techniques

Polygonatum kingianum is a common medicinal herb that grows in shady, damp mountain shrublands and grassy areas at forest edges. It is cold-tolerant, and seedlings can overwinter in the field, but it is not suitable for growing in dry areas. So, what are the cultivation techniques for Polygonatum kingianum?

1. Site selection and land preparation

Choose a moist plot with adequate shade. The soil should preferably be loam or sandy loam that is loose in texture and has good water-holding capacity. Before sowing, deep-plow once. While preparing the land, apply 2000 kg of farmyard manure per mu, plow it into the soil as base fertilizer, then harrow finely and level the ground, and make beds 1.2 m wide.

2. Field management

During the early growth stage, cultivate and weed frequently, once each in April, June, September and November every year. Shallow hoeing is advisable, along with appropriate earthing up; in the later stage, simply pull the weeds. If drought occurs, or if planted in a relatively sunny, dry spot, water promptly. Every year, topdress in conjunction with cultivation and weeding. After the first 3 cultivations, apply 1500 kg of farmyard manure per mu, together with 50 kg of superphosphate and 50 kg of cake fertilizer. Mix thoroughly, open furrows between the rows and apply, then cover with soil to bury the fertilizer. Polygonatum is intolerant of waterlogging and prefers shade, so attention should be paid to drainage and intercropping with corn.

3. Pest and disease control

The common pests and diseases of Polygonatum kingianum are black spot disease and white grubs. Black spot disease mostly occurs in spring, summer and autumn, damaging the leaves. Control methods: clean the garden at harvest time and destroy diseased residues; spray 1:1:100 Bordeaux mixture in the early stage, once every 7 days, 3 times in a row.

White grubs damage plants in the larval stage, attacking the roots, biting through seedlings or gnawing the roots of the seedlings, causing broken seedlings or hollow roots, and the damage is severe. Control methods: seed treatment with 75% phoxim emulsifiable concentrate at 0.1% of the seed amount; or, during the field outbreak period, drench with a 1000-fold dilution of 90% trichlorfon.

4. Harvesting and processing

Harvest generally in spring and autumn, with autumn harvest being of better quality. For cultivated plants, harvest in autumn of the 3rd to 4th year after the aboveground parts wither. Dig up the rhizomes, remove the aboveground parts and fibrous roots, wash off the soil, steam in a steamer until they appear oily and glossy, then take them out and sun-dry or oven-dry them; or boil them in water, then scoop them out and sun-dry or oven-dry them.

5. Seed preservation techniques

Polygonatum can be propagated by rhizome and by seed, but in production it is better to use rhizome propagation. In late autumn or early spring, around the latter part of March, select robust, disease-free plants, dig up the underground rhizomes and use them directly as propagation material for planting.

Polygonatum kingianum prefers shade, so during cultivation, be sure to avoid direct sunlight and sunscald.