Choosing a greenhouse plastic cover means balancing light transmission against durability. The right film lets in the PAR spectrum plants crave while standing up to snow loads, high winds, and relentless UV exposure. A poor choice leads to rips mid-season, cloudy plastic that starves your seedlings, or material that degrades before your second growing cycle.
I’m Mohammad Maruf — the founder and writer behind Gardening Beyond. I spend my time comparing polyethylene densities, analyzing UV additive blends, and studying owner feedback across dozens of film and tarp options to find real-world longevity data for greenhouse growers.
This guide focuses on the specific specs, durability claims, and real customer experiences that separate a true greenhouse plastic cover from a general-purpose construction sheet that will yellow and crack under the sun.
How To Choose The Best Greenhouse Plastic Cover
Selecting the correct greenhouse film involves more than just picking the lowest price per square foot. You need to weigh UV stability, proper thickness, light diffusion, and the physical characteristics of the plastic against your specific climate and crop needs. A film that works for a temperate zone hoophouse will fail within months in a high-altitude desert environment.
Mil Rating and Mechanical Strength
6 mil is the baseline for most budget to mid-range greenhouse films. It is light enough to allow high light transmission and easy handling, but it is more vulnerable to punctures from sharp frame edges or hail. Moving up to an 8 mil or 16 mil film adds significant tear and puncture resistance but reduces clarity slightly. The trade-off is often worth it if you experience high winds or deal with abrasive frame materials.
UV Resistance and Lifespan
Not all clear plastic is the same. Cheap construction-grade sheeting will yellow and crack within one growing season because it lacks UV inhibitors. Look for “UV treated” or “UV resistant” in the product specs. A 4-year UV rating means the film is formulated to maintain its integrity through multiple cycles of intense sunlight. Without this, the polymer chains break down, leading to brittle failure.
Light Transmission and Diffusion
Clear films offer the highest light transmission, which is critical for seedlings and high-light crops like tomatoes. Some growers prefer a slightly diffuse film to eliminate hot spots and prevent leaf burn. Anti-drip coatings are another consideration—they cause condensation to run down the film in sheets instead of dripping on your plants, reducing disease pressure.
Installation and Grommets
Thin films (6 mil) are usually installed by sandwiching the edge between frame channels or using wiggle-wire. Heavy-duty tarps with grommets (16 mil) are easier to tension with ropes but rely on grommet spacing to handle wind loads. Ensure the grommets are reinforced and the spacing suits your frame structure. Improperly secured panels can rip at the grommet point in high winds.
Quick Comparison
On smaller screens, swipe sideways to see the full table.
| Model | Category | Best For | Key Spec | Amazon |
|---|---|---|---|---|
| Farm Plastic Supply 8 mil (16’x25′) | Premium Film | Long-term hoop houses, extreme weather | 8 mil, 4-Year UV Rating | Amazon |
| Ansgery 16 Mil Clear Tarp (10x20FT) | Heavy Tarp | Small structures, high puncture risk | 16 mil, Grommets every 18 inches | Amazon |
| chicarry 6 mil Clear (10 x 50ft) | Mid-Range Film | Mid-size greenhouses, anti-drip needs | 6 mil, 5-Layer Co-Extrusion | Amazon |
| Film-Gard 6 Mil (10’x100′) | Construction Sheeting | Vapor barriers, temporary protection | 6 mil, Opaque-frosted finish | Amazon |
| warmfarm 6 Mil Clear (8ftx25ft) | Budget Film | Mini greenhouses, small tunnels | 6 mil, Tear-resistant PE | Amazon |
| Aluf Plastics 6 Mil (20’x100′) | Large Roll | Large coverage, general use | 6 mil, LDPE Material | Amazon |
| Farm Plastic Supply White 6 mil (10’x100′) | Opaque Sheeting | Light-blocking, vapor barrier | 6 mil, Opaque White | Amazon |
In‑Depth Reviews
1. Farm Plastic Supply 8 Mil Clear (16’x25′)
This 8 mil film from Farm Plastic Supply hits the sweet spot for serious growers. The 4-year UV stabilizer package means it can handle multiple seasons of intense sun without becoming brittle. Owner reviews confirm it survived hail, small tornado events, and heavy snow loads without catastrophic failure. The premium polyethylene construction provides noticeably higher tear resistance than standard 6 mil options.
The dimensions measure 16 feet wide by 25 feet long, making it ideal for a mid-size hoop house or a robust cold frame. The light transmission is excellent, though some users report slight cloudiness developing after 18-24 months of outdoor exposure. This is normal for any UV-treated film and doesn’t significantly affect plant growth. The material is packaged tightly in a single roll, which simplifies installation.
Long-term value is where this product separates itself. While the upfront cost is higher than entry-level sheeting, the 4-year lifespan means a lower annual cost of ownership. One review noted it held up for 1.5 years in strong winds with no issues. If you are building a permanent or semi-permanent greenhouse structure, this film is the benchmark.
What works
- True 8 mil thickness with high tensile strength
- 4-year UV stabilizer package for long-term durability
- Proven resilience in severe weather and snow
What doesn’t
- Some cloudiness develops after extended UV exposure
- Higher initial price point than 6 mil films
2. Ansgery 16 Mil Clear Tarp (10x20FT)
This is not a standard film — it is a woven and double-coated polyethylene tarp with a 16 mil thickness. The reinforced edges and brass grommets every 18 inches make it a beast for withstanding high winds and physical abuse. Multiple owners use it on chicken coops and exposed greenhouse frames, reporting that it held up to ice storms and heavy rain without tearing.
The clarity is reduced compared to thinner films because of the three-layer woven construction. It is translucent, not crystal clear, which diffuses light well and reduces hot spots. The size options are practical for small to medium structures, and the pre-installed grommets eliminate the need for wiggle-wire or channel systems. You can rope it down and tension it quickly.
Warm reminder from the manufacturer: in extreme winds with improper fastening, the grommets can pull out. This is a limitation of any tarp-style cover versus a channel-mounted film. If you need maximum longevity in a calm climate, a standard film may be better. But for structures that face repeated high wind events, the sheer physical thickness of this tarp wins.
What works
- Extremely thick 16 mil woven construction
- Reinforced edges with dense grommet spacing
- Proven resilience in ice storms and high winds
What doesn’t
- Lower light clarity compared to clear films
- Grommets can pull out in extreme wind if not secured correctly
3. chicarry 6 mil Clear (10 x 50ft)
The chicarry film uses a 5-layer co-extrusion process that provides better mechanical strength than single-layer 6 mil sheeting. The standout feature is the anti-drip coating, which eliminates water droplets that can burn foliage by focusing sunlight like a lens. It has a slightly hazy appearance due to this coating, not a clarity flaw.
At 10 feet wide and 50 feet long, it offers generous coverage for a mid-size greenhouse tunnel. Owner reports confirm it held up through fall and winter, including snow loads that stayed on the surface for days. The tear resistance is respectable, and the material has a slight stretch that helps with tensioning on warm days. Multiple users used it to protect chicken runs from freezing temperatures.
The UV stability is adequate for seasonal use, but it is not marketed as a multi-year film. Expect it to last 12-18 months before showing signs of UV degradation in full-sun environments. For the price, this is a solid choice if you are willing to replace it annually or if you need the anti-drip feature for a high-humidity greenhouse.
What works
- Effective anti-drip coating reduces leaf burn risk
- 5-layer construction adds tear resistance
- Good coverage area for the price point
What doesn’t
- Hazy appearance due to anti-drip layer
- UV lifespan is shorter than premium 8 mil options
4. Film-Gard 6 Mil (10’x100′)
Film-Gard is a construction-grade 6 mil sheeting, not a dedicated greenhouse film. It is designed for vapor barriers, concrete curing, and dust containment. The recycled content gives it a frosted, opaque appearance with very low light transmission. This makes it unsuitable for greenhouses where you need maximum PAR light, but excellent for side walls or as a windbreak where you don’t need to see through it.
The mechanical toughness is surprisingly good for 6 mil. Reviews mention it handling shovel drags, zip ties, and severe weather without tearing. One user noted it lasted nearly 10 years as a protective cover, though it was not in direct UV sunlight year-round. In direct sun, the lack of UV stabilizers means degradation will happen faster than with dedicated films.
For growers, this product is best used as a secondary layer or a winterizing wrap where clarity is not a priority. The massive 10×100 foot roll provides extensive coverage for large structures. If you need a see-through cover, skip this one — it is definitely not clear. But for pure strength and coverage in a non-light-critical application, it is a workhorse.
What works
- Very durable for its mil rating due to quality LDPE
- Massive roll size covers large areas economically
- Excellent for vapor barriers and windbreaks
What doesn’t
- Not UV-stabilized — degrades in direct sun
- Opaque finish prevents light transmission for crops
5. warmfarm 6 Mil Clear (8ftx25ft)
The warmfarm 6 mil film is a straightforward, no-frills option for small-scale applications. It measures 6.5 feet wide by 19.7 feet long after unfolding — smaller than the packaging suggests, so careful measurement is essential. The polyethylene material is tear-resistant and includes UV protection, making it a legitimate entry-level greenhouse film for mini tunnels or cold frames.
Reviews are positive for its intended use. Users describe it as excellent thickness for the price, easy to cut, and perfect for winterizing windows or wrapping a small chicken run. It blocks cold air effectively and allows light penetration. A few users noted the size was smaller than expected, which is the main point of friction. If you need a precise fit over a 6×20 foot frame, this works well.
Limitations include the smaller size and the fact that it is a single-layer 6 mil film — it will not withstand heavy abrasive contact like a tarp will. For temporary seasonal protection or for a mini hoop house, it is a perfectly capable budget buy. Just measure your frame twice before ordering.
What works
- Good clarity and light transmission for seedlings
- Easy to cut and install for small tunnels
- Tear resistance is decent for the mil gauge
What doesn’t
- Smaller than expected dimensions after unfolding
- Single-layer 6 mil is less durable than thicker options
6. Aluf Plastics 6 Mil (20’x100′)
Aluf Plastics delivers a true heavy-duty 6 mil Low-Density Polyethylene (LDPE) sheet that prioritizes puncture resistance over clarity. At 2000 square feet per roll, this is designed for large projects where coverage area is the primary requirement. The material is translucent, not fully clear, and handles well for creating temporary wind barriers or covering extensive greenhouse frames.
User feedback emphasizes the thickness and toughness of this roll. Multiple reviews mention using it as a vapor barrier, a temporary wall, and a plant shelter during cold snaps. It resists punctures better than generic home improvement store sheeting and cuts cleanly with scissors. The drawbacks include the challenge of unrolling such a large sheet by one person and the general haziness that limits its use for light-sensitive crops.
This is a utilitarian choice. It is not a specialized greenhouse film with UV inhibitors or anti-drip coatings. For a temporary structure or a large-side-wall windbreak, the value per square foot is excellent. For a main greenhouse roof where light quality matters, you will want a dedicated clear film.
What works
- Excellent value per square foot for large areas
- High puncture resistance for 6 mil LDPE
- Versatile use for vapor barriers and covers
What doesn’t
- No UV stabilization — degrades in full sun
- Hazy appearance reduces light transmission
7. Farm Plastic Supply White 6 mil (10’x100′)
This white plastic sheeting from Farm Plastic Supply is the opposite of a greenhouse cover — it blocks light completely. The opaque white color is designed for vapor barriers, light-blocking walls, and dust containment. For growers, its best use is as a thermal curtain inside a greenhouse to partition space or to line the north wall for light reflection.
The 6 mil LDPE material is durable and easy to work with. Owners report using it for covering walls in workshops and as a moisture barrier in crawl spaces. It cuts easily and holds up to abuse. However, the lack of UV stabilizers and the opaque nature make it unsuitable as a primary greenhouse roof. The return policy is also noted as potentially expensive due to restocking fees and shipping costs.
If you specifically need a white, light-blocking, heavy-duty sheet, this is a quality product. Just be aware of its limitations for growing applications. It is a specialty item for specific construction or partitioning needs, not a general-purpose clear cover.
What works
- Durable 6 mil LDPE for tough applications
- Ideal for light-blocking or vapor barrier uses
- Large 10×100 foot roll for extensive coverage
What doesn’t
- Not UV stabilized for greenhouse use
- Opaque — blocks all light for plant growth
Hardware & Specs Guide
Thickness: The Mil Dilemma
Mil (thousandths of an inch) is the standard unit for plastic film thickness. A 6 mil film is 0.006 inches thick — it is light, flexible, and offers high light transmission. Moving to 8 mil adds significant tear resistance. Dedicated greenhouse films often use 6 or 8 mil, while non-greenhouse heavy-duty tarps can be 16 mil or thicker. Thicker is not always better for a greenhouse, as reduced light transmission can impact photosynthesis.
UV Stabilizers vs. Standard Poly
Standard construction-grade polyethylene lacks UV inhibitors. When exposed to sunlight, the polymer chains break down, causing yellowing, embrittlement, and cracking within months. Greenhouse-specific films contain UV stabilizers that absorb or block UV radiation, extending the film’s life to 2-4 years. The presence of “UV resistant” in the product description is the first sign of a film intended for long-term greenhouse use.
Woven vs. Extruded Construction
Most greenhouse films are extruded — a single layer of polyethylene. Woven tarps, like the 16 mil Ansgery, use a cross-hatch of fibers sandwiched between polyethylene layers. This provides extreme tear resistance but reduces clarity. For a greenhouse roof where light transmission matters, an extruded film is the standard. For side walls or windbreaks where puncture resistance is priority, a woven tarp can be a better choice.
Anti-Drip Technology
Standard film causes condensation to bead up and drip onto plants. This can promote fungal diseases and burn foliage by magnifying sunlight. Anti-drip films have a hydrophilic coating that changes the surface tension, allowing condensation to spread into a thin, clear sheet and run down the walls. This keeps the interior drier and provides better light transmission by reducing fogging. The trade-off is a slightly hazy appearance when dry.
FAQ
What is the best mil thickness for a greenhouse plastic cover?
How long does a UV-resistant greenhouse film typically last?
Can I use construction-grade plastic sheeting for my greenhouse?
What is the difference between a clear film and a clear tarp for greenhouses?
How do I calculate the size of plastic cover I need for my greenhouse?
Final Thoughts: The Verdict
For most gardeners, the greenhouse plastic cover winner is the Farm Plastic Supply 8 mil because it offers the best blend of thickness, multi-year UV protection, and proven weather resistance for a permanent structure. If you need extreme puncture protection for a small, exposed hoop house, grab the Ansgery 16 mil tarp. And for a budget-friendly seasonal tunnel on a tight budget, the warmfarm 6 mil film gets the job done without breaking the bank.