Detailed Explanation of High-Yield Bitter Melon Cultivation Techniques in Midsummer
"During the growth of bitter melon, water and fertilizer must be sufficient so that more melons can be set. On sunny days when the sun is fierce, water evaporates quickly, so watering must be done in time to avoid drought wilting, which affects plant growth and development and flowering and fruiting. During the high-yield period, when replenishing water, nitrogen, phosphorus and potassium fertilizers should also be supplemented in full..." On August 1, at the bitter melon planting base in Xianyan Village, Ma'an Town, Yilong County, Wang Daiyong, a senior agricultural technician of the county agricultural and animal husbandry bureau, explained to the villagers the field management techniques for high-yield bitter melon during the dog days.
Carry out intertillage in time
No grass shall be allowed on the open ground of the bitter melon field, the surrounding field ridges, or the ditches. From the seedling stage onward, bitter melon should be intertilled, weeded and earthed up in time to prevent soil compaction at the melon heads. Generally, after planting and watering to help the seedlings recover, the first intertillage is carried out when the surface soil is slightly dry and no longer sticky. If there are strong winds or the soil is too dry, water heavily once more before intertilling. The second intertillage can be carried out 10-15 days after the first. During this intertillage, care should be taken to protect new roots, and it is better to till shallowly rather than deeply. Each intertillage can be combined with the application of some high-quality farmyard manure, such as cake fertilizer, various types of poultry feathers, and decomposed chicken manure and pig manure. After trellising, when the vines have extended to more than 50 cm, the root system has basically spread throughout the entire row spacing, and generally intertillage should no longer be carried out. However, attention should be paid to pulling out weeds in time to prevent wild grass from growing densely, so as to improve field ventilation and light transmission conditions and reduce pest and disease damage. During the first intertillage, if missing seedlings or weak and diseased seedlings are found, replanting should be done in time to ensure a full stand. At the same time, plant training should be carried out well, promptly removing old, yellow and diseased leaves from the lower part of the trellis, as well as branches hanging down to the lower part that bear no melons. If possible, branches in the upper part that have no melons or female flowers should also be removed. Diseased and pest-damaged fruits should also be removed in time. All removed leaves, branches and fruits should be bagged and transported away for destruction.
Promote flowering as much as possible
Regularly spray small amounts of agents such as "Kaihuajing", "Cuguoling", "Penshibao", "amino acids", yunhuaisu, borax, monopotassium phosphate, and calcium nitrate.
Fertilizer and water management
Bitter melon has many fruiting cycles and a long harvest period, and consumes large amounts of water and fertilizer throughout its life. Therefore, fertilizer and water management is an important guarantee for achieving high yield.
In addition to applying sufficient base fertilizer, generally heavy topdressing is applied during vine extension, flowering and fruiting. The first topdressing is about 7 days after planting, and 10% concentration of decomposed human urine or 0.5% compound fertilizer water can be applied, then applied once every 5-7 days thereafter, with the concentration gradually increasing. By the time of flowering and fruiting, the concentration of human urine can be increased to about 30%. During the flowering and fruiting period, 2-3 heavy fertilizer applications should be made to extend the harvest period. Generally, at early flowering, apply 25-30 kg of cake fertilizer, 15-20 kg of compound fertilizer and 10 kg of urea per mu as a topdressing combined with earthing up; after the first harvest, continue to apply 20-25 kg of cake fertilizer and 20 kg of compound fertilizer as another topdressing; thereafter, after every 1-2 harvests, apply 30%-40% human urine or 10-15 kg of compound fertilizer. Topdressing should also be flexibly controlled according to weather and leaf color conditions, increasing or decreasing as appropriate.
Pest and disease control
Bitter melon commonly suffers from nematode disease, Fusarium wilt (grafted seedlings generally do not develop the disease), powdery mildew, phytophthora blight, anthracnose, and so on. The main insect pests are melon fruit fly and aphids.
Powdery mildew: It occurs during the flowering and fruiting period, covering the leaves with white powdery material, causing the leaves to lose greenness and turn yellow, resulting in premature aging of the plant. Control method: When white powdery material appears on the leaves, spray the leaf surface once every 7-10 days with an aqueous solution of cyproconazole, an aqueous solution of triadimefon, Cuibei, or an aqueous solution of sulfur suspension concentrate for control, spraying continuously 2-3 times. Note that the amount of medicinal solution must be large.
Phytophthora blight: On leaves, it mostly starts from the leaf tip or leaf margin. The lesions are irregular in shape with indistinct edges, initially dark green and water-soaked, later turning brown. The lesions can expand to cover the entire leaf or more than half of it. When humid, a ring of white mold grows at the junction of the lesions. Control agents: chlorothalonil, Yike, Bordeaux mixture, Nongliling, Anke, dimethomorph, fosetyl-aluminum, Sandofan or Ridomil Gold by spraying, and diseased leaves should be removed and taken away for destruction.
Stem borers: Spray and kill with triazophos, monosultap, bisultap, fipronil, and so on.
Aphids: Spray and kill with imidacloprid, acetamiprid, abamectin.
Melon fruit fly: The larvae bore into young melons, causing the young melons to become deformed and change color prematurely, after which they rot and deteriorate and also give off a foul odor. Control method: During the young melon stage, spray the young melons 2-3 times with an aqueous solution of fipronil, or an aqueous solution of Nongdile, or an aqueous solution of Kung Fu, once every 4-5 days, and promptly remove deformed fruits and burn or deep-bury them in a concentrated manner outside the garden.