The Latest Luo Han Guo (Monk Fruit) Planting Techniques and Methods Tutorial

Luo Han Guo is hailed by people as the “immortal fruit” and is a commonly used Chinese medicinal herb, with its fruit used as medicine, having the functions of clearing heat and moistening the lungs, and lubricating the intestines to relieve constipation. Besides being used domestically as medicine, it is also one of China's exported Chinese medicinal herbs. With the development of China's traditional Chinese medicine industry, demand will increase, and only by developing production can the growing need be met. Now let us take a look together at Luo Han Guo planting techniques!

Luo Han Guo's Growth Habits

Luo Han Guo likes to grow under climate conditions that are warm, have a long frost-free period, and have a large temperature difference between day and night. The suitable growth temperature range is 18-32°C. Under moist and foggy conditions with soil moisture content of 25-30% and relative air humidity of 75-85%, the plants grow and develop well. The soil should preferably be loam with deep soil layers, rich in humus, loose and moist, and well-drained.

Luo Han Guo Planting Techniques

1. Site selection and land preparation: According to Luo Han Guo's requirements for climate and soil conditions during growth and development, in areas at an altitude of 1000-1200 m, sunny hillside land should be chosen for planting, while in areas at 300-500 m, north-facing hillside land on the shady side should be chosen. Plow and harrow in the winter of the previous year. After weathering through the winter, plow once more several days before planting to make the soil loose and crumbly. Make beds 15-20 cm high and 130-150 cm wide, and open holes at a row spacing of 1.5-1.7 m and a plant spacing of 1-1.3 m. Apply 5 kg of decomposed barnyard manure per hole, mix the fertilizer thoroughly with the soil, and pile it into a mound 60 cm in diameter and 12-15 cm high, ready for planting.

2. Vine layering propagation: In production, Luo Han Guo is propagated by vine layering, carried out between July and October each year. During the peak fruiting period of the plants, select high-yielding individual plants as mother plants for vine layering propagation. These individual plants are not allowed to bear fruit on the trellis. By September, select vigorous vines with short internodes and flower buds for layering. The seed tubers obtained in this way can avoid flowerless plants. When layering, dig a hole 15-18 cm deep and 15-18 cm wide in the ground nearby, bend and press the tips of 3-5 vines into the hole, with about 12-14 cm of the tip seedlings pressed into the soil, and cover with soil 8-10 cm above the ground.

3. Planting method: Generally plant between March and April. When digging seed tubers, care should be taken to place female and male plants separately. When planting, match 1 male plant for every 20 female plants so that there is enough pollen for artificial pollination. Seed tubers must not come into contact with fertilizer. A thin layer of soil should first be placed over the fertilizer in the hole, then the tubers placed on the soil. Place 1-2 seed tubers per hole; when placing 2, the plant spacing should be about 30 cm. When placing them, the buds should face upward, exposed above the soil surface, and all facing the same direction for easy management. Finally, cover with soil 7-10 cm thick.

Luo Han Guo Field Management

1. Building trellises and supporting vines: Luo Han Guo is a vine plant and needs a trellis to climb on for the plants to grow well. After planting, begin building the trellis. Generally use bamboo and wood as supports, with the trellis about 1.7 m high. Spread small bamboo or tree branches on top of the trellis, then insert a small bamboo pole beside the plant so the stems and vines can climb upward. When the seedlings are 17-20 cm high, remove the side branches growing from the vine stems, leaving the main vine to promote rapid growth of the main vine. When the seedlings are 30 cm high, loosely tie the main vine to the bamboo with straw or hemp rope to help the stems and vines climb onto the trellis. If vines that have climbed onto the trellis fall down, they must be promptly put back on the trellis to favor vine growth.

2. Weeding and topdressing: Luo Han Guo requires weeding and topdressing many times each year. In April-May, when the seedlings are 30 cm high, apply 1 application of thin human manure water. In May, after the main vine has climbed onto the trellis, apply 1 application of decomposed barnyard manure and peanut bran. From June to September during the flowering and fruiting period, apply a mixed fertilizer of barnyard manure, peanut bran, phosphate fertilizer, etc. once every 7-15 days to promote fruit growth. Fertilization method: Open a semi-ring-shaped ditch on the upper side of the hillside 25 cm away from the tuber and apply the fertilizer there. Never apply fertilizer directly on the tuber.

3. Artificial pollination: Artificial pollination is an important technical measure in Luo Han Guo production. It can increase the fruit-setting rate of plants and increase yield. From June to July when the plants bloom, pick the open male flowers every morning. Use a bamboo stick to scrape out the pollen and gently place the pollen on the stigma of the female flowers. The pollen of each male flower can pollinate about 10 female flowers. Artificial pollination should be completed in the morning; pollination in the afternoon has poor results. Collected pollen should preferably be used the same day. If it is to be kept until the next day, it must be dried and stored, otherwise it will lose its germination ability.

4. Overwintering management: Every year before the Beginning of Winter, mound soil around the root crown about 15 cm thick, then cover with a layer of grass to prevent the tubers from freezing during winter. Around Qingming of the second year, remove the covering and dig away the soil to expose the tubers, sun them in the sunlight for 3-4 days, and at the same time cut off the withered vines to favor the growth of new buds.

Luo Han Guo Pest and Disease Control

1. Root-knot nematode disease is a disease caused by root-knot nematodes. After infection, tumor-like growths of varying sizes form on the fibrous roots, often in a bead-like string, while warty lumps form on the tubers. In mild cases, the plant roots' absorption of water and nutrients is affected; in severe cases, the roots and part of the tubers all rot. Newly reclaimed land can be used for planting, disease-free tubers should be selected as seed, and crop rotation should be practiced. After onset, exposing the root crown and cutting off the tumor-like growths and then applying tung oil has a certain control effect.

2. The yellow squash beetle is a major insect pest of Luo Han Guo. The larvae bite off the roots in the soil, and in severe cases the aboveground stems wither and die. The adults bite notches in the leaves, or eat all the leaves, causing the plants to die. When adults are causing damage, spray to kill them with 90% trichlorfon or 80% dichlorvos at 1000-1500 times dilution.

3. Fruit flies are an important insect pest harming Luo Han Guo fruits. From July to September, adults lay eggs inside the fruits, and the larvae bore into and feed on the flesh. Damaged fruits turn yellow and drop early. If damaged fruits are found, they should be picked off promptly, and fallen fruits on the ground should be cleared and burned in a centralized manner. During the adult activity period, use 50 g of 90% trichlorfon and 1.5 kg of brown sugar, mixed with 50 kg of water, and spray it on places where fruits and leaves grow densely to trap and kill adults.

4. Red spider mites harm Luo Han Guo leaves, tender vines, and fruits. In severe cases, they cause leaf and fruit drop. When they occur, spray with 80% dichlorvos at 800 times dilution or 40% dimethoate at 800 times dilution plus 20% tetradifon at 800 times dilution to kill the adults.

Luo Han Guo Harvesting and Processing

1. Timely harvesting: Luo Han Guo blooms and bears fruit in the second year after planting. From August to September, when the fruit changes from light green to old green or slightly yellow patches, the fruit stalk is withered and yellow, and the fruit feels hard and somewhat elastic when squeezed by hand, it can be harvested. Cut it off with scissors and place it down gently. Spread the harvested fruits indoors in a cool, ventilated place. After the moisture evaporates, spread them for 7-15 days. When the evaporated moisture accounts for about 15% of the fresh fruit weight and 50% of the surface is yellow, processing can begin.

2. Processing method: When processing Luo Han Guo, grade them into large, medium, and small and place them in drying boxes on a baking oven. The baking temperature should rise gradually from low, then decrease again later. During the first 20-24 hours, maintain 45-50°C, then gradually raise the temperature to 65-70°C and bake for 48-62 hours. When the fruit weight decreases noticeably, lower the temperature to 55-60°C and bake for another 48 hours. During baking, change the boxes once every morning and evening, swapping the positions of the upper and lower boxes, and interchange the positions of the fruits in the middle and at the edges. Turn each fruit up and down so it is heated evenly. Bake for about 7 days, so that 70%-75% of the fresh fruit weight in moisture is evaporated. When the fruit gives a sound when lightly tapped with a finger, it is dry. Remove the hairs from the fruit and it is the finished product.

3. Commercial specifications: Luo Han Guo is considered good when it is fully dry, brown, makes no sound when squeezed, has no rotten fruits, and is sweet. According to circumference size, it is divided into extra-large fruit (circumference above 20 cm), large fruit (circumference above 18 cm), medium fruit (circumference above 16.5 cm), small fruit (circumference above 15 cm), substandard fruit (circumference above 13.5 cm), and below-substandard fruit (circumference below 13.49 cm). Sounding fruits (those that make a sound when squeezed) are treated as one grade lower than their original grade, while broken fruits are counted by weight.