Peppermint cultivation method

[summary] aliases: Su mint, mint leaf, mountain mint, etc.

It is the dried aboveground name of mint (MentplocalyxBriq.) of Labiatae. It has the effects of dispersing wind and heat, clearing the leader, penetrating rash and so on. It mainly treats wind-hot cold, headache, red eyes, sore throat, mouth sore, measles and so on. It can also be used in spices, food, cosmetics and other industries.

The medicinal parts of peppermint are stems and leaves. It can be used for medicine after harvest and drying, or distilled to extract peppermint oil and menthol with fragrance, stomach-strengthening, wind-dispelling, sweating, antispasmodic, antipyretic, analgesic and other effects. The main ingredients in the ceremony are: menthol (that is, menthol), menthone and so on, of which menthol is its main component, colorless crystal and special aroma. To increase the initial amount of peppermint oil and menthol, on the one hand, it depends on the correct agricultural technology (such as correct harvest time and reasonable fertilization); on the other hand, the selection of good varieties is a key issue in menthol production.

The main growth and cultivation areas: mainly produced in Jiangsu, Jiangxi, Sichuan, Hebei, Shaanxi, Shandong and other provinces. It is cultivated all over the country.

[plant morphology]

Perennial herbs, plant height 30~80cm, the whole plant has a cool aroma. Underground rhizome white, creeping, tufted fibrous roots on nodes. Aboveground stems erect or base decumbent, square hollow nodes. Simple leaves alternate, ovate or oblong, margin serrulate, both sides sparsely pilose and yellow glandular dots. Verticillate inflorescence axillary. Corolla reddish or purple, lip-shaped; stamens 4; pistil 1, ovary 4-lobed. 4 nutlets, inserted in persistent stamens. Flowering from August to September and fruiting from September to October (Fig. 35).

[biological characteristics]

Peppermint likes warm and humid environment, the rhizome germinates in 5~6oC, and the suitable growth temperature is 20-30 ℃. Hardy, underground rhizome at 1 30 ~ 1 20. C can still survive the winter safely. During the growing period, there is plenty of sunshine, more moisture is required in the early and middle stages, and dry environmental conditions are needed in the budding and flowering stage. The requirement to the soil is not strict, the general soil can be planted. Peppermint has strong adaptability. The plants like to be moist in the early stage of growth, and it is better to dry the plants slightly after sealing ridges. The budding period prefers a sunny and dry climate.

Long sunshine plants of the genus mint. Long sunshine can promote flowering and increase the accumulation of peppermint oil and menthol.

[planting technology]

1. Selecting and preparing sandy loam land with sunny flat, fertile and convenient drainage and irrigation, applying circle fertilizer 5000kg, compound fertilizer 50kg, deep ploughing 20cm, raking fine and leveling, making a flat or high border with a width of 1m, and opening four small ditches with 3cm depth in the border to be planted.

2. Methods of reproduction

(1) Variety: at present, among many cultivated varieties, green stem round leaf and purple stem purple vein are the best, with high yield and high content of volatile oil. It can be planted in front and back of the house and in the courtyard.

In recent years, 73mur8 mint cultivated by Shanghai Flavor Industry Science Research Institute has many branches, short internodes, large leaves and dense distribution of glandular scales. The oil yield of fresh grass is 0.3% o.51%, the oil yield per mu is 9.75~15.22kg, and the content of menthol is 80.13%-87.6%. It is a high-yield variety and has been widely planted in production areas.

(2) Propagation: the method of rhizome reproduction is generally adopted in production. Shandong and other places are planted in spring, while Jiangsu and Zhejiang are planted in winter. It is planted in spring from "the Spring Equinox" to "Qingming Festival" and in winter from late October to early November. When planting, dig out the unplaned rhizome left in the field or cultivate the planed rhizome with wet soil in winter. Select the rhizome with short internodes, white color, sturdy, dense nodes and no diseases and insect pests. Cut into long sections of 6~1Ocm, put them in the open ditch according to row spacing 24cm and plant spacing 8cm, cover with soil and pour thoroughly. Roots should be cut and planted while planing to prevent excessive water loss from affecting survival. About 60~1O0kg of seed stem per mu. Generally, 1 mu of mint root can be divided into 5 mu and 10 mu.

3. Field management

(1) watering and fertilization: peppermint grows rapidly, and the annual harvest times are different in different areas. In order to accelerate the growth of mint and increase the yield of peppermint, sufficient fertilizer must be applied. Sichuan base fertilizer is generally based on stable fertilizer, cake fertilizer and bone meal. In addition to applying base fertilizer, topdressing should be carried out on time. After peppermint emergence, it is necessary to loosen the soil and weed frequently to keep the field clean and tidy. And frequently irrigated with small water and immediately irrigated in case of drought to keep the soil moist and promote the growth of its stems and leaves. 15cm in seedling height and topdressing in time after each harvest, mainly nitrogen fertilizer (15kg urea per mu) or human feces and urine per mu 1500kg plus thiamine 8kg, water 50kg, ditching next to the seedlings. Supplemented with phosphate and potassium fertilizer (10kg diammonium phosphate). Watering after application can promote the rapid growth of stems and leaves.

(2) Prevention and control of diseases and insect pests

1) Rust: the pathogen is polysporum in fungi, which harms leaves. In the early stage of the disease, there was a pile of orange-yellow powdery summer spores on the back of the leaves, and a black-brown powdery pile of winter spores was produced in the later stage. In severe cases, the leaves withered and fell off. The disease is serious in the rainy and hot season in May.

Prevention and control methods: timely discharge of stagnant water in the ground, reduce soil moisture; spray 1000 times of 25% strychnine at the initial stage of the disease for 2 or 3 times in a row.

2) White star disease: also known as spot blight. It is a fungus of echinococcosis, which harms leaves. It happened from May to October. At the beginning of the disease, near-round dark green spots appeared on both sides of the leaf, then expanded continuously, showing dark brown, and then faded into gray-white, white star-shaped, upper small black spots, causing the leaves to die and fall off.

Prevention and control methods: spray 1000 times of carbendazim at the beginning of the disease, use a maximum of 2 times per season, and the last application is not less than 5 days from the harvest interval, or use Bordeaux solution of 1, 1 and 150, alternately, the effect is better.

4. Selection and breeding of improved varieties

Two varieties of green stem round leaf and purple stem purple vein with strong growth were selected as improved varieties. Frozen water should be poured before freezing in winter and planed again in the next spring. The rhizome can also be dug out before freezing, tied into a small handle, buried deeply or cultivated in wet soil indoors for planting in the following spring.

[harvest processing] peppermint is harvested twice a year in Jiangsu, Zhejiang and Jiangxi, and once or twice a year in North China, the first in "Lesser Heat" and the second in "Frosts Descent". Sichuan, Fujian and Guangdong can harvest 3 or 4 times a year. Choose a sunny day when there is no overcast or rain in recent days, cut the mint to the ground with a sickle, expose it on the spot for 2 hours, then sun for another 2 hours, transport it back to 78% dry, tie it into small bundles, and then dry it to the whole dry. It is generally believed that the "volt leaves" were harvested for the first time from June to July, with good quality, and the lower quality "autumn leaves" were harvested in August.