Fine Preparation of Soil Before Laying Mulch Film: It’s essential to finely prepare the soil before laying the mulch film. Residual straw, stones, branches, and other hard objects in the soil can easily puncture the mulch film, affecting its effectiveness. These should be removed promptly.
Ensure Mulch Film Adheres to the Ground Without Excessive Stretching: The mulch film should adhere closely to the ground without being overly stretched to prevent mechanical damage, which can affect later recovery.
Soil Covering on Film Edges and Regular Checks: The edges of the mulch film should be covered with soil to a depth of 7-10 cm. In windy areas, soil should be added every 2-3 meters along the surface and the sides of the film should be buried deeper. For high-bed cultivation, press the film into the bottom of the furrow to prevent the wind from lifting it off the bed sides. Recheck the film 3-4 days after application and promptly cover any gaps or loose areas, being careful not to damage the seedlings.
Benefits of Using Mulch Film
Increases Soil Temperature: Mulch film helps raise soil temperature and conserve moisture during winter and spring. The soil temperature under the mulch film is generally 2°C-3°C higher than uncovered soil, promoting early seedling emergence and development. Different colors of mulch film have varying effects on temperature: clear film is the most effective, while silver-gray film does not increase temperature, and black film is opaque, slow to warm, and suppresses weeds. In summer, black film cools and controls weeds more effectively, making it ideal for summer and autumn crops. Silver-gray film, also known as anti-aphid mulch film, is effective for crops like cucumbers, tomatoes, watermelons, peppers, celery, lettuce, spinach, and tobacco. For cost savings, adding 6-8 silver-gray stripes (2 cm wide) on clear or black mulch film provides aphid and virus protection.
Reduces Soil Temperature Fluctuations: Mulch film suppresses soil temperature increases in summer and prevents temperature drops in winter.
Enhances Fertilizer Efficiency and Soil Nutrition: Mulch film prevents fertilizer leaching from sunlight and rain, regulates soil temperature, and strengthens plant root absorption. Improved soil temperature and moisture conditions boost microbial activity, promoting the decomposition of organic and mineral matter, thereby increasing soil nutrients.
Improves Soil Physical Properties: Soil under mulch film has a lower bulk density and higher oxygen content due to reduced rainfall impact, benefiting root growth. Reduced soil erosion prevents soil compaction and improves physical and chemical soil properties.
Reduces Water Evaporation and Field Humidity: Mulch film significantly conserves water and reduces humidity, thereby lowering disease incidence.
Increases Light Efficiency: The reflection from clear mulch film and water droplets underneath increases near-surface reflected light, improving crop light conditions and enhancing photosynthesis and organic matter accumulation.
Prevents Soil Salinization: By moving soil moisture from bottom to top, mulch film maintains high surface moisture content, reducing soil salt concentration and preventing salinization.
Suppresses Weed Growth and Reduces Pest Damage: The reflective properties of mulch film, especially silver film, repel aphids, significantly reducing virus diseases.
Promotes Early Crop Harvest: Mulch film accelerates crop growth and development, leading to earlier product formation, particularly boosting early yield in winter and spring crops, thereby increasing total yield.
Common Misconceptions about Mulch Film (Case Studies)
Mulch film is crucial in agricultural production, playing a key role in regulating soil temperature, conserving water and fertilizer, and extending the cultivation period. It improves soil physical properties, suppresses weed growth, and reduces disease. However, improper use can negatively impact crop growth, especially in greenhouse vegetable production.
Case 1: Mulch Film Close to Stem Base, Severe Plant Death
Farmer Louis experienced widespread plant death in his bell pepper crop, with stems rotting and turning black. The disease, known as “black stem,” resulted from high humidity at the stem base. Condensation from soil evaporation under the tightly fitted mulch film created a high-temperature, high-humidity environment, promoting disease.
Case 2: Mulch Film Tightly Covering Entire Greenhouse, Affecting Root Growth
Farmer Frank’s spring tomatoes grew weakly, with thin stems and yellow leaves. Investigation revealed the tightly fitted mulch film reduced soil-air gas exchange, especially after watering, hindering root respiration and nutrient absorption. Experts recommend using wire or bamboo poles to elevate the mulch film, improving soil aeration and reducing humidity.
Case 3: Early Mulch Film Application for Autumn Vegetables, Hinders Root Growth
With decreasing temperatures, cucumber growers started covering mulch film using the “perforation method.” Covering mulch film immediately after planting can cause high temperatures and moist environments at the surface, hindering root development. It’s suggested to cover the film 15 days post-planting to encourage strong root growth.
Case 4: Only Covering Operation Rows with Mulch Film, Ineffective
Some farmers cover only operation rows, leaving planting rows uncovered. This approach fails to reduce greenhouse humidity or enhance temperature. Covering operation rows reduces soil aeration, affecting root growth. Experts suggest covering planting rows to lower humidity and enhance temperature control.
By understanding and correcting these misconceptions, farmers can better utilize mulch film to improve crop health and yield.