When to sow Artemisia selengensis? Key points on planting methods and variety selection

Artemisia selengensis, also known as ludiao, narrow-leaf mugwort, water mugwort, green mugwort, etc., is a common wild plant found along lakes and grassy shoals. Because of its insecticidal and dampness-removing properties, it is widely cultivated. So when is Artemisia selengensis sown? What are the planting methods? Which variety is good to grow?

1. Variety selection

The commonly used varieties of narrow-leaf mugwort are Xiaolizi Large-leaf Mugwort and Xiaolizi Fine-leaf Mugwort. Xiaolizi Large-leaf Mugwort, also known as willow-leaf mugwort. The leaves are pinnately trifid, the tender stems are green, with a strong fresh fragrance, thick and tender; it is relatively cold-tolerant, disease-resistant, sprouts early, and has high yield.

2. Sowing and seedling raising

1. Seedling raising time: raise seedlings from June to August each year, and the seedling age is generally 25 to 35 days.

2. Field preparation and fertilization: the ratio of seedling field to main field is 1:3 to 4. Field preparation should meet the standards of level field and broken soil, soaked field and clean grass, and loose topsoil with firm subsoil. Before field preparation, apply sufficient base fertilizer. Use 1500 to 2000 kg of farmyard manure and 5 to 10 kg of 45% high-quality compound fertilizer per mu, or alternatively use 1000 kg of farmyard manure, 100 to 120 kg of cake fertilizer, and 10 to 15 kg of 30% compound mixed fertilizer per mu. Fertilization should be carried out 7 days before seedling raising. Base fertilizer must not be applied in holes or broadcast after sowing, so as to avoid fertilizer damage to seedlings. The seedling bed width is preferably 1.5 to 2.0 m including ditches.

3. Seedling treatment: for seedlings, it is best to use aboveground stems, and underground stems can also be used. When using aboveground stems, first strip off the stems and leaves, then cut the stems into small sections 4 to 6 cm long, ensuring each section has 2 intact axillary buds or 2 nodes, then soak the small sections in water. During soaking, add 30 g of carbendazim and 1 g of ABT rooting powder per 100 g of water. After 4 to 5 hours, remove and dry in the shade until sowing.

4. Sowing: this model uses layering propagation. In the prepared seedling field, use a hoe 15 to 20 cm wide to dig sowing rows, then sow the seedling sections in the rows at 150 to 180 sections per sq m, and finally cover with soil 1 to 2 cm thick. Sowing should be done when there is sufficient soil moisture or before rain.

5. Seedbed management:

(1) Common pests during the seedling stage include aphids, cabbage caterpillars, etc. The main diseases are gray mold and downy mildew. Pest control follows the principle of “apply pesticide when pests are seen.” For disease control, before the rows close, apply protective agents such as cymoxanil · mancozeb and fosetyl-aluminum.

(2) If drought occurs before and after emergence, timely drought relief should be carried out to protect seedlings.

(3) Apply herbicide after sowing and before emergence. The selected chemicals include alachlor or trifluralin, etc., at about 0.2 kg per mu; alternatively, apply after emergence with chemicals such as haloxyfop-R-methyl, fluazifop-P-butyl, quizalofop-P-ethyl, etc.

3. Land preparation and fertilization

(1) It is advisable to choose sandy loam soil with a previous crop not of the Asteraceae family, good irrigation conditions, and fertile soil. Before planting, carry out plowing and sunning (freezing) of the soil clods;

(2) Apply sufficient base fertilizer: 3000 to 4000 kg of decomposed organic fertilizer or 150 kg of decomposed cake fertilizer per mu, plus 30 kg of high-quality compound fertilizer; open beds with a width of 1.5 to 2.0 m including ditches.

4. Planting out

Use a small hoe or other tool to dig small rows, place the small seedlings in the rows, and firm the soil. The standard for transplanting seedlings is: green leaves, thick stems, and seedling length 15 to 18 cm. The planting row spacing is 15 cm, plant spacing is 5 to 6 cm, and 60000 to 70000 plants are planted per mu.

5. Field management

1. Water and fertilizer management: narrow-leaf mugwort is moisture-tolerant but not drought-tolerant. In hot and dry seasons, water frequently to keep the field moist and promote growth. After planting, narrow-leaf mugwort seedlings must be watered with survival water, using 1000 to 3500 kg of water per mu. After they survive, according to seedling condition, splash-irrigate once with clear manure water or 1% urea water. Before mulching in winter, loosen the soil shallowly and broadcast 10 kg of urea or 20 kg of high-quality compound fertilizer per mu, and water promptly in case of drought. After the Start of Spring, apply another round of clear manure water to promote stem and seedling growth.

2. Cultivation and weeding: the underground stems of narrow-leaf mugwort are mainly distributed within the 5 to 10 cm soil layer. After planting and establishment, promptly pull out weeds in the field and loosen the soil by cultivation to promote good root development and accumulate more nutrients.

3. Temperature management: after the aboveground part is killed by frost in early to mid-November, remove the narrow-leaf mugwort stems level with the ground, clear dead branches, fallen leaves, and weeds from the field, and after fertilizing and watering for 5 to 7 days, cover with a greenhouse, while also covering with plastic film inside the greenhouse or covering with small arched tunnels. When the daytime greenhouse temperature (large, medium, or small tunnel) exceeds 25°C, uncover the film for ventilation. Plastic film can also be used to directly cover seedlings in the main field, with the covering period starting from the first frost and ending at harvest the following year. If the daytime temperature in winter and spring exceeds 5°C, attention should be paid to uncovering the film to prevent old, weak seedlings and spindly seedlings, so as not to reduce their marketability.

4. Thinning: when the seedlings grow to about 3 cm, thin them in time, keeping 3 to 4 small seedlings per clump. Otherwise, too many seedlings will cause crowding and affect the marketability of Artemisia selengensis.

5. Building sheds for cold protection: the optimum temperature for Artemisia selengensis is 20 to 25°C. After October, the temperature gradually decreases. When the temperature is below 10°C or there is frost, the stems and leaves wither and Artemisia selengensis grows slowly, but Artemisia selengensis overwinters by underground stems, and the underground stems can sprout above 5°C. To ensure that Artemisia selengensis reaches the market during New Year's Day and the Spring Festival, a shed should be built before the temperature drops to 10°C in mid-to-late November for heat preservation and frost protection. Use 0.08 cm thick drip-free film for covering. The shed length is 35 to 40 m, width 4.5 m, height 1.7 m, preferably oriented north-south. Keep the temperature inside the shed at 18°C to 23°C on sunny days. At noon on hot days, open both ends of the shed for ventilation, so as to avoid excessive growth due to excessively high temperature and to avoid rotting or blackening of Artemisia selengensis caused by excessive humidity and poor ventilation. Remove the covering film promptly when the temperature rises after the Spring Festival.

6. Pest and disease control: narrow-leaf mugwort has relatively strong resistance to pests and diseases. The main diseases are gray mold and root rot, and the main pests are aphids and cabbage caterpillars. For root rot in the early stage, irrigate the roots with 800-fold solution of 50% carbendazim wettable powder, or 800-fold solution of 58% metalaxyl · mancozeb wettable powder. For gray mold in the early stage, spray with 1000-fold solution of 50% procymidone wettable powder. For cabbage caterpillars, use 1500-fold solution of 5% flufenoxuron dispersible liquid concentrate. For aphids, use 2000-fold solution of 20% imidacloprid wettable powder.

6. Scientific harvesting

When the tender shoots of Artemisia selengensis grow to 15 to 25 cm, the central leaves at the top have not yet spread, and the color is light green, harvest close to the bed surface. When the temperature is suitable, harvest about once every 30 days; when the temperature is low, harvest about once every 50 days. After cutting the stems, except for keeping a few central leaves, remove all other leaves. Grade and tie into bundles according to different thicknesses, then soak in clean water, cover with a wet cloth, and place in a cool place. After 8 to 10 hours of softening, they can be marketed.

7. Reasonable seed reservation

After the last harvest in March, select a field reserved for seed seedlings, generally reserving sufficient area at a ratio of 1:5. If the land area is small, first reduce the seed reservation field, and after the previous crop is harvested before June to July, increase the area for propagation. The management method of the seed reservation field is the same as above.