Imagine your greenhouse bathed in uniform, soft light, with crops thriving and yields steadily increasing—all achieved simply by selecting the right plastic covering material. The productivity, durability, and energy efficiency of a greenhouse largely depend on the quality of its covering material.

Materials like polyethylene (PE), polycarbonate, polyvinyl chloride (PVC), ethylene-vinyl acetate copolymer (EVA), and reinforced polyester mesh each offer distinct advantages. Their light transmission, insulation properties, UV resistance, and replacement costs directly impact your bottom line. Let's explore these materials' characteristics, benefits, and lifespans, along with professional recommendations tailored to different climates and crops.

Currently, the two most widely used plastic covering materials for greenhouses globally are ethylene-vinyl acetate copolymer (EVA) and polyethylene (PE).

EVA is a covering material copolymerized from ethylene and vinyl acetate, offering exceptional optical and mechanical properties that provide crops with ample light and protection.

• Superior light transmission: EVA film maximizes sunlight penetration, ensuring crops receive sufficient photosynthetic energy.
• Excellent mechanical properties: The film offers good tensile and tear resistance, withstanding certain wind pressures and external impacts.
• Efficient insulation: EVA film effectively reduces heat loss inside the greenhouse, lowering energy consumption.
• Strong light degradation resistance: With added UV inhibitors, EVA film resists ultraviolet erosion and extends service life.

Polyethylene (PE) is currently the most widely used greenhouse covering material, valued for its low cost, easy processing, and strong adaptability. PE films are typically divided into single-layer and multi-layer (co-extruded) types, with various additives available to enhance UV resistance, tear resistance, and light diffusion properties.

• Light transmission: Single-layer PE film offers 85-90% light transmission, while multi-layer PE film (with better light diffusion) achieves 80-88%.
• Light diffusion: PE films with anti-fog and homogeneous diffusion additives reduce harsh shadows, promoting uniform crop growth.
• Service life: In temperate climates, PE films last 3-5 years; in tropical climates without enhanced UV protection, lifespan drops to 2-3 years.
• Cost: PE film is low-cost and available in various thicknesses (100-200 microns) and performance grades.

Recommended for: Short-cycle vegetable production (e.g., lettuce, beets), arched greenhouses, and low-cost initial projects.

Polycarbonate is a rigid panel material, typically 4-16mm thick, offering outstanding mechanical strength and insulation properties, making it ideal for permanent greenhouse structures.

• Light transmission: Polycarbonate panels achieve 88-92% light transmission, providing crops with ample sunlight.
• Insulation performance: With a U-value (heat transfer coefficient) of 1.8-3.5 W/m²K, these panels significantly reduce heating and cooling costs.
• UV resistance: The outer layer is co-extruded to prevent yellowing for 10 years, offering excellent UV protection.
• Cost: Polycarbonate panels are moderately priced but offer good value due to their durability and low maintenance.

Polyvinyl chloride (PVC) panels offer good flexibility and fire resistance, though their light diffusion is inferior to PE film.

• Light transmission: PVC panels provide 80-85% light transmission, meeting most crops' needs.
• Durability: These panels last 5-7 years with moderate UV resistance.
• Characteristics: PVC panels are self-extinguishing and can be field-welded for easy installation and maintenance.
• Cost: PVC panels are moderately priced with average installation costs.

Recommended for: Research greenhouses, ornamental nurseries, and locations with high safety (fire resistance) requirements.

Reinforced plastic mesh combines PVC or PE plastic with an internal polyester grid, delivering exceptional tear and wind resistance.

• Light transmission: The mesh offers 75-85% light transmission, sufficient for most crops.
• Mechanical strength: Highly durable, this material is ideal for windy regions and moderate hurricane zones.
• Service life: Lasting 8-10 years, it provides long-term greenhouse protection.
• Cost: While more expensive, it delivers excellent ROI in extreme climates.

Recommended for: High-wind areas, moderate cyclone zones, or long-term projects requiring maximum reliability.

• Light transmission and diffusion: Match materials to crop types. Leafy crops prefer high diffusion, while flowering crops need maintained PAR (photosynthetically active radiation).
• UV resistance and climate cycles: In tropical areas, prioritize multi-layer films with enhanced UV stabilizers.
• Total cost of ownership: Consider not just initial cost but lifespan and energy savings (polycarbonate and EVA).
• Installation and slope: Maintain a 5-10% slope to prevent water and dirt accumulation; test proper tension to avoid sagging.
• Maintenance: Clean annually with water and mild detergent; inspect hardware and anchors every six months.

Selecting the right greenhouse plastic is crucial for maximizing light exposure, temperature control, and covering longevity. Professional guidance can help identify the optimal solution based on climate, crops, and budget considerations.