Detailed Explanation of Cultivation Methods and Planting Techniques for Honeysuckle

The dried flower buds or newly opened flowers of honeysuckle (Lonicera japonica Thunb.), a perennial plant of the Caprifoliaceae family, are used medicinally; the dried stems and vines are used as honeysuckle stem in medicine. Honeysuckle has the effects of clearing heat and detoxifying, cooling and dispersing wind-heat, and is used for carbuncles, boils and sores, wind-heat common cold, seasonal febrile diseases with fever, etc.; honeysuckle stem has the effects of clearing heat and detoxifying, dispelling wind and dredging collaterals, and is used for seasonal febrile diseases with fever, heat-toxin blood. Main growing and cultivation areas: wild plants are found throughout the country. It is mainly produced in Henan and Shandong. The product from Shandong (Pingyi, Feixian, etc.) is called "East Honeysuckle" and has a large output; the product from Henan (Xinmi, Fengqiu) is called "South Honeysuckle" and "Mi Honeysuckle" and is of good quality; both are genuine regional medicinal materials. The above production areas are all in mountainous regions, in a semi-cultivated and semi-wild state. At present, in relevant areas of Henan, Shandong and other provinces, on the plains it is completely cultivated and managed artificially, changing from clump-growing to single-stem upright growth, and from two crops of flowers to four crops of flowers, with the yield per mu increased to 150 kg. [Plant Morphology] Honeysuckle is a perennial small shrub or trailing plant. The old stems are gray or brownish-gray, and the young stems are densely covered with brown soft hairs; the stems are green or reddish-brown. Leaves are opposite; the leaf blades are ovate or oblong-elliptic, entire, with dense short soft hairs on both surfaces and margins; reticulate veins. Flowers are borne in pairs in the leaf axils; the peduncle is densely covered with short soft hairs, and at the base of the pedicel there are 2 leaf-like bracts, green; outside the calyx there are 2 small bracts enclosing it, the calyx is short and small, pale green, 5-lobed, with triangular lobes. The corolla is labiate, 3-4 cm long, the upper lip of the corolla is 4-lobed, recurved upward, the corolla tube about 2.5 cm long, densely covered inside and outside with soft hairs; the flower is white when first opened, later becoming golden yellow. Stamens 5; filaments white, inserted at the mouth of the corolla tube; anthers oblong, pale yellow or deep yellow, dorsifixed. Pistil 1; stigma papillary; style slender, both style and stamens protrude beyond the corolla; ovary inferior, 3-loculed, apical placentation, with 2 ovules per locule. Berry globose, 3-4 mm in diameter, green, purple-black when mature. Seeds gray-black, trigonous, about 1.5 mm long and about 1 mm wide. Flowering period May-August, fruiting period June-October (Figure 31). [Biological Characteristics] There are two common larger varieties of honeysuckle. One is "Damaohua", with long internodes, strong twining ability, and mostly hairy flowers. The other is called "Jizhuahua", with shorter internodes, strong upright growth, and flower buds concentrated in a chicken-claw shape. The "Xianhua" variety from Fengqiu, Henan, is similar to "Jizhuahua". Its upright growth is stronger, and the flower buds are more compact. Honeysuckle has very strong vitality and a very developed root system. The sprouting rate of branches is also very strong. It can be propagated by seed, but in production, cutting propagation and division propagation are more often used. With cutting propagation, under plain cultivation it flowers in 2 years, forms a clump in 4-5 years, and reaches the peak flowering period. It declines only after 15-20 years and needs renewal. Old flower clumps can live for more than 30 years. Honeysuckle does not have strict requirements for climatic conditions and has strong adaptability. It is cold-resistant and heat-resistant, drought-resistant and waterlogging-resistant. However, in cold high-mountain shady areas, growth and development are poor, the growth period is short, and the yield is low. Its adaptability to soil is also strong. It grows vigorously in deep, fertile soil. It can also grow in poor, lightly saline-alkali soil with a salt content of 0.2%-0.4%, but development is poorer and yield is lower. 1. Growth and development habits The annual growth and development stages of honeysuckle can be divided into 6 periods, namely the budding period, the new shoot vigorous growth period, the bud appearance period, the flowering period, the slow growth period and the overwintering period. In Henan and Shandong, under artificial cultivation conditions, the flowering period is relatively concentrated, from mid-May to early September, and after opening 4 times, sporadic opening ends in late September. The first flowering (commonly called the first crop of flowers): mid-to-late May, the bud amount accounts for 40% of the total bud amount of the entire flowering period. The second flowering (commonly called the second crop of flowers): late June, the bud amount accounts for 30% of the total bud amount of the entire flowering period. The third flowering: late July to early August, the bud amount accounts for 20% of the total bud amount of the entire flowering period. The fourth flowering: early September, the bud amount accounts for 10% of the total bud amount of the entire flowering period. After entering the slow growth period, the plant grows slowly, leaves fall off, and new branches are no longer formed, but green bud bodies appear at the stem nodes of the branches, and a large number of overwintering buds form at the main trunk stem or branch crotches of the main branches; this period should be the period of nutrient return for storage. When the daily average temperature is 3°C, growth is in an extremely slow state, the overwintering buds turn reddish-brown, but some leaves remain green through the winter without falling. In production, it is divided into 10 growth stages. Due to different climatic conditions in different places, the growth period of honeysuckle differs greatly. 2. Flowering habits: Honeysuckle has the habit of multiple shoot flushes and multiple flowerings. In the Huang-Huai Plain of Henan, the flowering period of honeysuckle is from mid-May to the end of September. Under conditions of no management and allowing natural growth, generally the first crop of flowers has a large flower quantity and a concentrated flowering period, budding and opening in mid-to-late May and ending in early June. After that, flower buds form only when strong branches produce secondary branches, with a small flower quantity and irregular flowering period. If management is strengthened, with artificial pruning, rational fertilization and irrigation, then the flowering period can be controlled each year so that it flowers relatively concentratedly 3-4 times. The yield and quality of honeysuckle at different stages are shown in Table 7. [Honeysuckle Planting Techniques] Because honeysuckle is a vine plant, long-term artificial cultivation has developed it into a semi-shrub form. When cultivating, the choice of plant type is very important, and the plant variation is also very great. In production, Henan Province has divided honeysuckle into 9 variety types and 2 major strain groups: the Xianhua strain and the Maohua strain, based on variations in crown, branches, leaves and flowers. The main varieties are: Damaohua, Qingmaohua, Changxianhua, Xiaomaohua, Duorui Yinhua, Duohua Yinhua, Qutouhua, Hongtiao Yinhua and Xianhua. The excellent varieties promoted on a large scale are: Damaohua, Qingmaohua and Changxianhua. According to preliminary statistics, Shandong has more than 10 varieties, which can basically be divided into 3 major strain groups, namely the Maohua strain, the Jizhuahua strain and the wild Yinhua strain. The main varieties are: Damaohua, Xiaomaohua, Damaye, Da Jizhuahua, Xiao Jizhuahua, wild Yinhua; there are also varieties such as Elin, Duihuazi, Yelicang, Yeliqi, Xianhuazi, Zijingzi, etc. Among them, Damaohua and Jizhuahua have high yield and good quality, are excellent varieties in production, and are also the two varieties with the largest cultivation area in the production areas. 1. Site selection and land preparation It is divided into two methods: mountain cultivation and plain cultivation. (1) Mountain cultivation: usually cultivated on the terraced field ridges of mountain slopes, and can also be cultivated in concentrated patches on mountain slopes and hilltops, but due to the limitations of water, fertilizer and climatic conditions, the yield per unit area is still not high. Cutting seedling transplanting and direct cutting methods are commonly used for cultivation. (2) Plain cultivation: usually the clumping and twining habit of honeysuckle is changed, and artificial pruning is carried out to make the stem an upright small shrub. The seedling transplanting method is commonly used. For ease of management, flat plots conducive to irrigation and drainage are better. Before transplanting, apply 3000-5000 kg of fully decomposed organic fertilizer per mu, either by deep plowing or hole application, then harrow, level and firm the soil. 2. Propagation methods The method commonly used in production is cutting seedling propagation. Wherever irrigation conditions exist, cuttings can be made in all four seasons, but generally winter cuttings, spring cuttings and cuttings in the rainy season are common. Seedlings raised by winter and spring cuttings can be dug out for afforestation in about half a year by the rainy season; seedlings raised by cuttings in the rainy season can be planted in winter and spring. As long as the cutting nursery land can remain moist on the surface, the survival rate can generally reach more than 90%. (1) Selection of cuttings: Select robust, plump 1-2 year old branches, cut them into cuttings about 30 cm long, retaining about 3 nodes. They can also be collected in combination with summer pruning and winter pruning, and after collection cut into 25-30 cm branch sections. When using fruiting mother branches as cuttings, several short stubs should preferably be retained at the upper end. (2) Cutting: On a leveled seedbed, open furrows at a row spacing of 30 cm and a furrow depth of 20 cm. After the furrows are opened, bury the cuttings upright in the furrows at a plant spacing of 5-10 cm, or loosen the soil only without digging furrows, insert the cuttings 1/2-2/3 into the holes, and press firm. After a bed or a block is finished cutting, water along the furrows promptly to settle the soil so that the cuttings and soil are in close contact. After the water seeps down, cover with a thin layer of soil to preserve moisture and warmth. After the cuttings are buried in soil, it is suitable for 5-8 cm to be exposed above, so as to facilitate new bud germination and cutting. (3) Management after cutting: Nursery land management should be strengthened. According to soil moisture, water timely, loosen soil and weed. For summer cuttings, after 7-8 days, the buds begin to sprout, and after more than ten days roots begin to grow. For winter and spring cuttings, generally roots grow first and then sprouts. When seedlings suffer from pests and diseases, they should be controlled promptly. (4) Transplanting: Carry out before early spring germination or during the autumn-winter dormant period. On the prepared planting land, dig holes at a row spacing of 130 cm and a plant spacing of 100 cm, 30-40 cm wide and deep, mix sufficient base fertilizer with the subsoil and apply it into the holes, plant 1 strong seedling per hole, fill with fine soil and press firm, then water thoroughly to settle the roots. 3. Field management (1) Intertillage and weeding: For concentrated production high-yield orchards, full intertillage management should be carried out. If cultivated on mountain slopes, hills, mountain gullies or field ridges, it is suitable to loosen the soil in holes around the plants, with a diameter of 60-70 cm, shallow hoeing near the plant and deep hoeing on the outside. (2) Timely watering: Generally, water once before freezing to warm the roots, then after the soil thaws in the next spring, water 1-2 times to moisten the roots and awaken them, and thereafter before each crop of flower buds is harvested, water once in combination with fertilization to promote buds and protect flowers; each topdressing should be combined with irrigation. When the soil is dry, water timely to facilitate new shoot growth of honeysuckle plants, which can promote multiple flowerings. (3) Fertilization: Honeysuckle is a perennial medicinal plant that buds and flowers multiple times, so fertilization should be carried out multiple times a year. Research shows that phosphate fertilizer and nitrogen fertilizer have good yield-increasing effects, but the combination of organic fertilizer and inorganic fertilizer is even better. According to the development pattern of honeysuckle and the need for harvesting flower buds, generally fertilizer should be applied at least twice a year. The first time is before freezing, mostly with organic fertilizers such as compost or barnyard manure, which not only helps the plant resist cold and keep warm, but also promotes vigorous growth in early spring; 5 kg of compost or barnyard manure can be used per plant, mixed with 50-100 g of chemical fertilizer; the second time is after the first crop of flower buds is picked, 5-10 kg of human manure and urine or 50-100 g of chemical fertilizer can be applied per plant; thereafter, according to the actual need for cultivating multiple crops of flower buds, each time a crop of flower buds is picked, apply 1 application of quick-acting nitrogen fertilizer. Fertilization method: bury in the soil in combination with deep loosening, or open a ring-shaped furrow 30-35 cm around the plant, 15-20 cm deep, apply the fertilizer into the furrow, then fill and cover the furrow with soil, and water timely after fertilization. Where conditions permit, after the plant buds, spray once with a mixed solution of potassium dihydrogen phosphate and urea at a concentration of 0.5%. [Harvesting and Processing] 1. Harvesting (1) Harvesting period: The harvesting period of honeysuckle is generally from May to August. The most suitable picking standard is: "the flower buds turn from green to white, white above and green below, swollen at the upper part, not yet open." The flower buds at this time, according to flowering stage classification, are the erbai stage and dabai stage. The picking time is very time-sensitive; from dawn to before 9 a.m. is the most suitable time to pick flower buds; after drying they are blue-green or green-white, bright in color, and the drying ratio is high, with an average of 4.2 kg of fresh product producing 1 kg of dry product. According to the picking stage, they are divided into first crop flower buds and second crop flower buds. With good light, heat, water and fertilizer conditions, and correct and timely summer pruning and pinching management, 3-4 crops of flower buds can also be harvested. The bud picking period can be extended from mid-to-late May to mid-September. The first crop of flower buds is picked around "Lixia" to "Xiaoman", for about 10 days, and generally the picking amount is largest in the last 5 days; the second crop of flower buds is picked around "Xiazhi" to "Xiaoshu"; the third crop of flowers is picked around "Dashu" to "Chushu"; the fourth crop of flowers is picked after Bailu. The ratio of the harvested amount of the 4 crops of flower buds is 4:3:2:1. (2) Picking method: The containers used for picking honeysuckle must be ventilated and breathable; generally bamboo baskets or wicker baskets are used, and schoolbags, handbags or plastic bags, etc., must not be used, in order to prevent the water evaporated from the picked flower buds from being unable to dissipate and then soaking the flower buds again, or the temperature being unable to dissipate and causing heating, mold and blackening. The picked flower buds should all be gently placed into the container, and "pick lightly, hold lightly, place lightly" should be achieved.