(I) Plant Characteristics and Variety Introduction
1. Plant Characteristics: The vine can grow up to 9 meters long, with hollow stems and multiple branches. The leaves are opposite, oval or elongated oval, measuring 3-8 cm in length and 1-3 cm in width, with young leaves having short soft hairs and a gray-green underside. Flowers grow in pairs in the axils or at the tips of flowering branches, with two leaf-like bracts. The flower stalk and flowers have short soft hairs. The corolla is white when first opened, turning golden yellow after 2-3 days, hence the name Honeysuckle (金银花). The calyx is small and 5-lobed, with triangular lobes. The corolla is slightly bilabiate, measuring 3-5 cm in length, with the tube part approximately equal to the lip part. The upper lip has 4 shallow lobes, while the lower lip is not lobed, and the outside is covered with soft hairs and glandular hairs; there are 5 stamens, and the ovary is hairless, with the style slightly longer than the stamens, all extending beyond the corolla. The berries are spherical, turning black and shiny when ripe.
2. Variety Introduction: There are many varieties of Honeysuckle, with two notable varieties in the main production area of Shandong.
(1) Da Mao Hua (Large Hair Flower), commonly known as Mao Hua, has a stout, short, and loose growth habit. Flowers do not grow at the tips of flowering branches but in the leaf axils. The flowering branches are robust, with large flower buds, longer branches that are easy to twine, bloom later, and have a developed root system that is drought-resistant and tolerant of poor soil, making it suitable for cultivation in mountainous fields.
(2) Ji Zhua Hua (Chicken Claw Flower) has flower buds concentrated at the tips of flowering branches, resembling chicken claws. The branches are thick, short, and upright, with a compact growth habit. It blooms earlier than Da Mao Hua, but the flower buds are smaller, making it suitable for dense planting in fields.
(II) Growth Habits: The root system is well-developed with many fine roots and strong rooting ability. Cuttings and branches that touch the ground can root in less than 15 days under suitable temperature and humidity. A ten-year-old plant can have a root crown diameter of 300-500 cm, with roots reaching depths of 150-200 cm. The main root system is distributed in the top 10-50 cm of soil, while the fibrous roots mainly grow in the top 5-30 cm. Roots grow fastest from early April to late August. As long as there is sufficient moisture and the temperature is generally not lower than 5°C, the plant can sprout year-round, with the most buds appearing in spring. Young branches are green and densely covered with short hairs, while older branches lose their hairs, and the bark is brown, later peeling off after new bark forms.
Honeysuckle prefers a mild climate, with an optimal growth temperature of 20-30°C, and thrives in a humid environment with high moisture and good air permeability. However, excessive soil moisture can affect growth, causing leaves to yellow and drop. It prefers long daylight hours; insufficient light can affect photosynthesis, leading to slender, small leaves, increased twining, and reduced flower bud differentiation. Therefore, it should be planted in well-lit areas and is not suitable for intercropping with trees.
Honeysuckle is resilient, drought-resistant, cold-resistant, tolerant of poor soil, and salt-alkali tolerant. Leaves do not fall off at -10°C, seeds germinate at around 5°C, and it can grow in areas with about 0.3% salinity.
(III) Cultivation Techniques
1. Site Selection and Land Preparation: Honeysuckle is not very demanding on soil and can be cultivated on barren hills and ridges, with sandy loam being the best. A pH of 5.5-7 is suitable for Honeysuckle growth, with the best soil being fertile, deep, and loose sandy soil. Before planting, apply 30-45 tons of manure per hectare, plow to a depth of 25-30 cm, rake, level, and thoroughly water the area, either making beds or not.
2. Propagation Methods: Propagation can be done by seeds and cuttings. Cuttings have a higher survival rate and quicker returns, making them commonly used in production areas.
(1) Seed Propagation: In November, harvest the fruits, wash them in water to remove the pulp and empty seeds, and dry the viable seeds for later use. In April of the following year, soak the seeds in warm water at 35-40°C for 24 hours, then mix with 2-3 times the amount of moist sand to induce germination. When the seeds split about 30%, they can be sown. Before sowing, select fertile sandy loam, plow to a depth of 30-33 cm, and prepare flat beds about 65-70 cm wide, with no restrictions on length. After preparing the beds, water thoroughly, wait for the soil to dry slightly, level the bed surface, and mark 3 shallow furrows at a spacing of 21-22 cm, placing the seeds evenly in the furrows about 1 cm apart. After sowing, keep the surface moist, and cover with a layer of straw, spraying water every two days. Germination will occur in about ten days. Seedlings can grow up to 1 meter tall in the same year. After growth stops in autumn, cut the upper branches, leaving 30-40 cm, and transplant in early winter or the following spring. The seed quantity per hectare is about 15 kg.
(2) Cutting Propagation: This can be done through direct cuttings or nursery cuttings.
1. Direct Cuttings: In areas with good water conditions, cuttings can be done year-round, usually during the rainy season or in early winter combined with pruning. Select robust, disease-free, and heavily flowering 1-2 year old branches, cut into 30-35 cm lengths, and remove the lower leaves for cuttings. In prepared land, dig holes with a spacing of 165 cm between rows and 150 cm between plants, with a depth of 16-18 cm. Place 5-6 cuttings per hole, spaced apart and slanted, with 7-10 cm above ground. Firm the soil around the cuttings, and water immediately after planting to improve survival rates. Specific row and plant spacing can vary based on terrain. In flatland, planting can be done after winter wheat, combined with pruning, cutting healthy branches with 2-3 side branches, and planting 4500 plants per hectare in holes.
2. Nursery Cuttings: To save Honeysuckle branches and facilitate management, nursery cuttings are often used. The method is to select a site convenient for watering, deeply plow and level the ground, using organic fertilizer as base fertilizer. In July-August, open furrows with a spacing of 23-26 cm, about 16 cm deep, and a plant spacing of 2 cm. Place the cuttings at an angle in the furrows, then cover and compact the soil. Water after planting, and if the weather is dry, water every two days to keep the soil moist. In about half a month, roots and buds will form, and they can be transplanted in the following spring or autumn.
3. Field Management
(1) Management in Mountainous Areas: In mountainous areas with poor soil and water conditions, Honeysuckle growth is relatively weak. Therefore, management focuses on light pruning, shaping, and promoting growth for newly planted stocks, while established plants focus on light pruning to stabilize and increase yield. For plants that have been transplanted for one year, before winter or before spring sprouting, cut the upper branches, leaving 30-40 cm to cultivate the main stem. Each spring, promptly remove new basal branches while retaining good side branches. Through years of pruning, the main stem should be prominent, with evenly distributed and vigorous branches, forming an umbrella shape. For productive plants, after flowering, cut off the upper parts of flowering branches, ensuring the branches can stand upright, while also removing old, dense branches to maintain vitality. Pruning improves ventilation, light conditions, and nutrient distribution within the plant, reducing pest and disease occurrence. Under similar conditions, pruning in mountainous areas can increase yield by 20%-30% compared to not pruning.
Before winter freeze, mound soil to prevent root damage. In early spring, open a circular trench 30 cm from the plant, 15 cm deep, apply fertilizer, and then cover with soil. The amount of fertilizer depends on the size of the flowering plant, generally applying 5 kg of organic fertilizer or 50 g of ammonium bicarbonate per plant for those over five years old. If growth is vigorous and soil is fertile, avoid applying nitrogen fertilizers. After fertilization, shape the plant into a fish scale pit to retain moisture.
(2) Management in Flatland: In flatland with fertile, deep soil and good water conditions, management focuses on pruning and shaping, selecting varieties with short internodes, strong upright growth, and abundant flowering to ensure stable and high yields. In flatland cultivation of Honeysuckle, through four years of shaping and pruning, the main stem reaches 30-40 cm in height and 6-8 cm in diameter, with several robust side branches above the main stem, densely covered with flowering branches, resulting in a conical shape with a height of 1.5-1.7 meters and evenly distributed branches. After five years of cultivation, the yield can reach 2.25 tons of dried flowers per hectare. The specific method is to cultivate the main stem and select secondary branches in the first year, leaving 4-7 strong branches outside 30-40 cm from the main stem in winter, maintaining appropriate angles between branches, and cutting off all other branches, retaining 5-7 pairs of buds. Then, cut the upper parts of the branches to fix the secondary branches. In the third year, in addition to adjusting the secondary branches, focus on selecting tertiary branches, retaining 3-5 robust branches as tertiary branches on each secondary branch, with a total of 20-30 tertiary branches selected for the entire plant. Each tertiary branch should retain 4-6 full buds, cutting off all upper branches to fix the tertiary branches, thus shaping the overall plant. In the fourth year, normal flowering age is reached, and during pruning, in addition to adjusting tertiary branches, focus on selecting flowering mother branches and the number of full buds on flowering branches. Following the principle of retaining strong and removing weak, each tertiary branch should retain 4-6 flowering mother branches, controlling the total number of flowering mother branches to around 100, and cutting off all other buds except for 4-6 full buds to facilitate flower bud emergence, laying the foundation for a bountiful harvest.
In the fifth year, entering the peak production period, during pruning, continue to adjust tertiary branches while mainly retaining flowering mother branches, ensuring annual replacement and retaining strong and vigorous branches to facilitate flower emergence. After each flowering, prune flowering branches to ensure they can stand upright after pruning. Through pruning, combined with watering and fertilization, promote the formation of vigorous and uniform new flowering branches, while concentrating the flowering time. This way, four harvests can be obtained in a year.
Pruning Time: Winter pruning is done from winter until before the next spring sprouting, combined with shaping. Summer and autumn pruning is generally done after each flowering, retaining appropriate flowering branches while promptly cutting off crossing branches, twining branches, weak branches, and old branches to moderate tree vigor and improve ventilation and light conditions. Both winter and summer-autumn pruning should be timely and based on the tree’s condition, adapting to local conditions. The principle is to perform heavier winter pruning and lighter summer pruning, with short cuts promoting flowering and controlling crown width.
Fertilization and Watering: Adequate water and fertilizer are key to achieving high yields in flatland cultivation. After thawing in early spring, for flowering plants over five years old, apply 750 kg of soybean cake per hectare along with appropriate organic fertilizer, digging trenches beside the plants. After each flowering, apply 225 kg of urea per hectare. Before freezing, apply fertilizer once, evenly spreading organic fertilizer on the ground, 30 cm from the Honeysuckle plants, and plowing to a depth of 25 cm to mix the soil and fertilizer evenly, cutting off old lateral roots to promote new root growth, thus warming the roots and fertilizing the plants. After each fertilization and thawing, water thoroughly to promote bud and leaf emergence.
4. Pests and Their Control: Honeysuckle has few diseases, mainly including juvenile honeysuckle brown spot disease, white silk disease, and powdery mildew; pest damage is more severe, mainly from aphids, coffee borer beetles, wood-boring moths, and inchworms.
(1) Honeysuckle Brown Spot Disease: This is a fungal disease. After infection, the lesions on the leaves are round or polygonal limited by leaf veins, yellow-brown, and gray mold appears on the underside in humid conditions. The disease is most severe in July-August. Control methods: Remove diseased branches and fallen leaves to reduce the source of pathogens; strengthen cultivation management, increase organic fertilizer application to enhance disease resistance; spray 3% Jinggangmycin at 50 mg/kg or 1:1.5:200 Bordeaux mixture at the initial stage of the disease, every 7-10 days for 2-3 times.
(2) White Silk Disease: This mainly affects the root and stem parts. High temperatures and heavy rainfall can easily cause outbreaks, with lower incidence in young plants and higher in older plants. Control methods: In spring and autumn, dig up and dry the roots, scrape the root parts, and irrigate with Bordeaux mixture, digging a 30 cm deep trench around diseased plants to prevent spread.
(3) Powdery Mildew: This mainly affects new shoots and tender branches. Control methods: Apply organic fertilizer to improve disease resistance; strengthen pruning to improve ventilation and light conditions; during winter pruning, try to cut off diseased buds to eliminate overwintering sources; spray 0.1-0.2 Baume degree lime-sulfur mixture in early spring when the buds are breaking and leaves are not yet unfolded.
(4) Chinese Honeysuckle Round-Tailed Aphid and Carrot Microtubular Aphid: Both adults and nymphs suck the sap from the leaves, causing leaf curling and yellowing, with damage occurring during the flower bud stage, leading to yellow and deformed flowers. During the process, they secrete honeydew, resulting in sooty mold, which affects leaf photosynthesis. The carrot microtubular aphid migrates from the first host, the Umbelliferae family, to Honeysuckle in October, mating and laying eggs to overwinter, with the most severe damage occurring in early to mid-May, significantly affecting the yield and quality of Honeysuckle, before migrating back to the first host in June. Control methods: Spray 40% dimethoate emulsion at 1000 times dilution or 80% dichlorvos emulsion at 1000-1500 times dilution every 7-10 days for 2-3 times, with the last application at least 10-15 days before harvesting Honeysuckle to avoid pesticide residues affecting quality.
(5) Coffee Borer Beetle: This is a significant stem-boring pest of Honeysuckle, distributed in the old production areas of Shandong, especially in Pingyi and Feixian. Surveys show that the damage rate of plants over ten years old can reach 80%. After being damaged, Honeysuckle growth weakens, and if damaged for several consecutive years, the entire plant may die. In Shandong, there is one generation per year, with larvae initially boring into the surface of the main stem, and when they grow to 3 cm, they bore longitudinally into the main stem, forming winding and tortuous tunnels. The holes are filled with sawdust and frass, making them hard to detect, and at this stage, chemical control is ineffective. Control methods: In April-May, during the adult emergence period and the initial hatching period of larvae, spray 80% dichlorvos emulsion at 1000 times dilution for effective control of both adults and newly hatched larvae. In recent years, releasing parasitic wasps in the field has achieved good control results, with the best time for release being in July-August on sunny days with temperatures above 25°C, making this biological control method suitable for promotion in production areas.
(6) Leopard Moth: In Shandong, there is one generation per year. After hatching, larvae bore into branches or new shoots, causing them to wilt within 3-5 days. When the larvae grow to 3-5 mm, they excrete frass from the entry holes, making them easy to detect. The larvae create a ring of damage between the wood and bark, making branches prone to breakage in the wind. The affected side often has several frass holes, with the frass being long cylindrical, light yellow, and not easily broken. In September-October, dead plants may appear. This pest has a habit of migrating to other plants. Control methods: Timely clean up the plants, and after the second harvest, it is essential to prune off infested branches between late July and early August. If pruning is delayed, larvae may bore into lower thick branches, affecting flowering growth. Late July is the peak hatching period for larvae, making it the active period for chemical control, using 40% oxydemeton-methyl emulsion at 1500 times dilution, adding 0.3%-0.5% kerosene to promote penetration of the solution into the stems. This method has shown good results.
(7) Willow Branch Moth: In the main production area of Shandong, there is one generation every two years, spanning three years. After hatching, larvae initially cluster under the old bark of Honeysuckle, and when they grow to 10-15 mm, they gradually spread. However, the larvae often bore into the phloem and shallow xylem from the main stem and root collar, creating extensive tunnels, excreting large amounts of frass and sawdust, severely damaging the plant’s physiological functions and obstructing nutrient and water transport, causing Honeysuckle leaves to yellow and drop, with flowering branches wilting in August-September. Control methods: Strengthen field management, as larvae prefer to infest weakened plants. Most larvae enter through old holes, so enhancing care management, timely fertilization, and watering can promote robust growth and improve resistance. For chemical control, during the peak hatching period, spray 40% oxydemeton-methyl at 1000 times dilution with 0.5% kerosene, or after harvesting flowers, irrigate the roots with 40% oxydemeton-methyl or 50% chlorpyrifos emulsion mixed at a 1:1 ratio, digging a hole around the plant 10-15 cm deep, applying about 20 ml per plant, adjusting based on plant size, and then covering the hole with soil. Due to the high concentration of the solution, safety precautions should be taken during use.
(8) Honeysuckle Inch Worm: This is an important leaf-eating pest of Honeysuckle. During outbreaks, leaves can be completely consumed, leaving only branches. Control methods: Clean the fields to reduce overwintering pest sources; during the larval stage, spray 80% dichlorvos emulsion at 1000-1500 times dilution for control.
(IV) Harvesting and Processing
1. Harvesting: Timely harvesting is crucial for improving the yield and quality of Honeysuckle. According to current cultivation techniques, Honeysuckle can be harvested four times a year. The first and second harvests yield more flowers, while the last two yield less. Generally, the first harvest occurs in late May, the second in late June, and the third and fourth in July and August, respectively. The flowering stages of Honeysuckle can be divided into seven stages: young buds (green, about 1 cm), three green (green, about 2.2-2.4 cm), two white (light greenish-white, about 3-3.9 cm), large white (white, about 3.8-4.6 cm), silver flower (just opened, white flower about 4-4.8 cm), golden flower (flower turning yellow, about 4-4.5 cm), and withered flower (brownish-yellow). The best medicinal materials are large white, two white, and three green, followed by silver flower and golden flower. The content of chlorogenic acid in the flowers decreases from the young bud stage to flowering. In production, it is essential to grasp the timing and standards for harvesting based on the flowering patterns of Honeysuckle. The most suitable time for harvesting is when the flowers are large and white, just opened. Harvesting too early results in small, greenish buds with low yield; harvesting too late leads to fully opened flowers, reducing quality. Harvesting should be done in the morning, preferably before the dew dries. Since Honeysuckle flowers open in a concentrated manner, it is crucial to harvest promptly. For buds that meet the harvesting standards, pick from the outside in, from bottom to top, taking care not to break the branches.
2. Processing: Honeysuckle should be dried or baked immediately after harvesting. Place the flowers on drying trays, spreading them on clean stones, cement floors, or mats, with a thickness of about 2 cm, aiming to dry them on the same day. Do not turn the flowers while drying to prevent them from turning black. It is best to use baskets or drying trays for drying. In rainy weather or if they cannot be dried on the same day, they should be collected and stored promptly. The drying method is simple and cost-effective, widely adopted in production areas.
In areas with concentrated flower production, to ensure the quality of Honeysuckle, or in rainy weather, drying methods should be employed. Different drying rooms can be designed according to local conditions, with farmers typically using natural baking methods, placing a coal stove in the center of the room (the number depends on the room size) to naturally expel moisture, generally drying at around 40°C without temperature variation.
A slightly more complex drying room design includes two stove openings at one end, with a backflow stove path inside, leaving a chimney and skylight on the roof, and a pair of ventilation openings on the front and back walls 30 cm above the ground. During drying, variable temperature methods are used, with the initial drying temperature not exceeding 30-35°C, drying for 2 hours, then increasing to around 40°C. After 5-10 hours, the indoor temperature should be maintained at 45-50°C, and after 10 hours, most of the moisture from the fresh flowers should be expelled, then increase the temperature to 55°C for rapid drying. Generally, drying for 12-20 hours can completely dry the flowers. During drying, do not use hands or other objects to turn the flowers, as this can easily cause them to turn black. If drying is stopped before the flowers are fully dry, they may spoil. Experiments in Pingyi County, Shandong, showed that the rate of first-class dried flowers reached over 95%, while the rate for sun-dried flowers was only 23%. The drying method is an effective measure to improve product quality in Honeysuckle production. Dried or baked Honeysuckle should be stored in a cool, dry place to prevent moisture and pests.
3. Specification and Grading: According to the quality of silver flowers and traditional production and sales habits, they are divided into three types: Mi Yin Hua (South Silver Flower), Ji Yin Hua (East Silver Flower), and Shan Yin Hua (Local Silver Flower), each further divided into several grades:
(1) Mi Yin Hua is referred to as “Mi Hua” in the Hong Kong market.
First Grade: Flower buds are rod-shaped, thicker at the top and thinner at the bottom, slightly curved. The surface is greenish-white, with thick corollas, slightly hard, having a fragrant aroma and a sweet, slightly bitter taste. No open flowers, broken buds, or yellow strips exceed 5%. No black strips, black heads, leaves, impurities, pests, or mold.
Second Grade: Open flowers do not exceed 5%, broken buds and yellow strips do not exceed 10%, no black strips or leaves. Other standards are the same as first grade.
Third Grade: Open flowers and black strips do not exceed 30%, no leaves, other standards are the same as first grade.
Fourth Grade: Both flower buds and open flowers are present, with no color distinction. Leaves do not exceed 3%. No impurities, pests, or mold.
(2) Ji Yin Hua is referred to as “Wu Hua” in the Hong Kong market.
First Grade: Flower buds are rod-shaped and robust, thicker at the top and thinner at the bottom, slightly curved, with a yellowish-white and greenish surface. They have a fragrant aroma and a sweet, slightly bitter taste. Open flowers do not exceed 5%. No tender buds, black heads, leaves, impurities, pests, or mold.
Second Grade: Flower buds are thinner, open flowers do not exceed 15%, and black heads do not exceed 3%. No leaves, impurities, pests, or mold.
Third Grade: Flower buds are small, open flowers do not exceed 25%, black heads do not exceed 15%, leaves do not exceed 1%, no impurities, pests, or mold.
Fourth Grade: Both flower buds and open flowers are present, with no color distinction, leaves do not exceed 3%, no impurities, pests, or mold.
Honeysuckle Network
WeChat ID: sdjyhxh
Editor for this issue: Lian Hui
Organized by: Shandong Honeysuckle Industry Association
Official website: http://www.sdjyh.gov.cn