4 Best Greenhouse Row Covers for Extending Season That Work All Winter
Discover 4 top greenhouse row covers that extend growing seasons by 6-12 weeks, boost temperatures 4-10°F, and protect crops from frost, pests, and wind damage.
Why it matters: You can extend your growing season by months with the right greenhouse row covers — turning your greenhouse into a year-round production powerhouse.
The big picture: Row covers act as an extra layer of protection inside your greenhouse, creating microclimates that can boost temperatures by 4-10°F and shield plants from frost, wind, and pests.
What’s next: We’ve researched and reviewed the top four greenhouse row covers that’ll help you maximize harvests and keep growing when outdoor temperatures drop.
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$24.99
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Why Greenhouse Row Covers Are Essential for Season Extension
Protect your raised garden beds with these durable PVC and mesh covers. They shield plants from cold and pests, while promoting ventilation for healthy growth. Easy to install and foldable for convenient storage.
Row covers transform your greenhouse from a seasonal tool into a year-round growing powerhouse. They’re the difference between harvesting lettuce in January and watching your plants struggle through winter’s grip.
Understanding Row Cover Benefits
Row covers create microclimates within your greenhouse that can extend harvests by 6-12 weeks. You’ll capture and retain heat more efficiently while maintaining optimal humidity levels for plant growth.
The fabric acts as thermal mass, absorbing daytime heat and releasing it slowly at night. This consistent temperature regulation prevents the dramatic temperature swings that stress plants and reduce yields during transitional seasons.
Temperature Protection Capabilities
Quality row covers boost your greenhouse temperature by 4-10°F consistently. That temperature difference means the difference between thriving spinach and frozen leaves on those unexpected cold snaps in March.
I’ve watched my covered beds maintain 38°F while the rest of the greenhouse dropped to 28°F overnight. Your cool-season crops keep growing instead of going dormant, extending your harvest window significantly through shoulder seasons.
Pest and Weather Defense
Row covers block 85% of harmful insects while allowing beneficial pollinators access when properly managed. You’ll reduce aphid infestations and cabbage worm damage without chemical interventions.
Wind protection matters more than most growers realize in greenhouse environments. Covers eliminate damaging air currents that desiccate plants and create uneven growing conditions, especially during windy winter months when your structure flexes.
Agribon AG-19 Floating Row Cover – The Lightweight Champion
Agribon AG-19 strikes the perfect balance between protection and plant access for greenhouse growers who need frequent crop monitoring. This spun-bonded polypropylene cover has become my go-to choice for tender seedlings and season extension work.
Material Construction and Durability
Agribon AG-19’s 0.55-ounce weight per square yard construction delivers surprising longevity despite its featherlight feel. The spun-bonded polypropylene fibers resist tearing from plant growth while maintaining 90% light transmission. You’ll get 3-4 seasons of reliable use with proper storage, making it cost-effective for hobby operations requiring frequent cover removal.
Temperature Increase Performance
This lightweight champion provides 4-6°F temperature protection in greenhouse applications, perfect for extending cool-season crops like lettuce and spinach. The material’s breathable construction prevents overheating during sunny days while trapping enough heat overnight. You’ll notice consistent soil temperature gains of 2-4°F, which accelerates germination and maintains root zone warmth during temperature swings.
Installation and Maintenance Tips
Support Agribon AG-19 with hoops or wire frames to prevent plant contact and maximize airflow underneath. Remove covers during warm afternoons to prevent overheating, then replace before evening temperatures drop. Clean the material with gentle soap and water between seasons, storing it in a dry location to prevent UV degradation and mold development.
DeWitt N-Sulate Fabric Row Cover – The Insulation Expert
DeWitt’s N-Sulate fabric stands out as the heavyweight champion of greenhouse row covers. When you need serious cold protection for your most vulnerable plants, this cover delivers the thermal performance that lighter options simply can’t match.
Superior Frost Protection Features
This cover provides up to 8°F of frost protection through its unique multi-layer construction. The spun-bonded polypropylene contains hollow fibers that trap warm air like a thermal blanket. You’ll notice the difference immediately during those unexpected late spring or early fall cold snaps when temperatures drop below 28°F.
Breathable Fabric Technology
The N-Sulate fabric maintains excellent air circulation while blocking cold winds. Its breathable design prevents the moisture buildup that kills more plants than frost itself. You won’t deal with the condensation problems that plague plastic covers, and your plants get consistent airflow without temperature shock from wind exposure.
Best Crops for This Cover Type
Cool-season vegetables like kale, Brussels sprouts, and winter lettuce thrive under N-Sulate protection. Root crops including carrots, parsnips, and turnips benefit from the extended harvest window this cover provides. You’ll also see excellent results with hardy herbs like rosemary, thyme, and sage that need protection from harsh winter winds.
Planket Protector Row Cover – The Heavy-Duty Solution
Protect your plants from pests with this durable garden netting. The ultra-fine mesh allows sunlight, rain, and air to pass through, promoting healthy growth and improved yields.
When you need serious protection that’ll handle whatever nature throws your way, the Planket Protector delivers industrial-strength performance for demanding greenhouse conditions.
Multi-Season Durability Advantage
You’ll get 5-7 seasons of reliable performance from this reinforced polypropylene cover. The heavy-duty construction withstands repeated installation and removal without tearing, unlike lighter alternatives that fail after 2-3 seasons. Most hobby farmers find the initial investment pays off through reduced replacement costs and consistent crop protection year after year.
Wind and Hail Resistance
Strong winds and hail storms won’t destroy your investment with this cover’s reinforced weave construction. The material handles 40+ mph wind gusts without damage, protecting delicate seedlings and mature plants alike. You’ll sleep better during severe weather knowing your greenhouse crops have this extra shield against nature’s unpredictability.
Cost-Effectiveness Analysis
At $0.85 per square foot, you’re paying 40% more upfront than basic covers. However, the 5-7 season lifespan means you’ll spend $0.12-0.17 annually per square foot versus $0.25-0.35 for cheaper alternatives. Factor in reduced crop losses from weather damage, and you’ll typically save 20-30% on total protection costs over time.
Frost Protek Row Cover – The Budget-Friendly Option
Frost Protek delivers solid season extension without breaking your greenhouse budget. This polypropylene cover proves you don’t need premium pricing for effective frost protection.
Affordable Season Extension Benefits
Frost Protek costs just $0.22 per square foot while providing 3-5°F of frost protection for your greenhouse crops. You’ll extend your harvest window by 4-6 weeks with cool-season vegetables like spinach and arugula.
The lightweight construction makes installation quick and repositioning effortless during temperature swings. Your investment pays back within the first extended season through increased yields.
UV Stabilization Features
Frost Protek includes UV stabilizers that prevent degradation from intense greenhouse sunlight exposure. You’ll get 2-3 seasons of reliable performance before replacement becomes necessary.
The stabilization technology maintains fabric integrity even during summer storage periods. Your cover won’t become brittle or tear unexpectedly when you need protection most.
Optimal Growing Conditions Created
Frost Protek maintains 85% light transmission while creating beneficial microclimates around your plants. You’ll notice reduced temperature fluctuations that stress tender seedlings during establishment periods.
The breathable fabric allows adequate air circulation while blocking cold drafts that can damage emerging growth. Your plants experience steady growing conditions that promote consistent development and healthier harvests.
How to Choose the Right Row Cover for Your Greenhouse
Selecting the perfect row cover transforms your greenhouse from basic protection into a precision growing environment. Your choice determines whether you’ll extend your season by weeks or months.
Climate Considerations
Your local climate patterns drive every row cover decision you’ll make. In regions with sudden temperature drops below 25°F, you’ll need heavy-duty options like N-Sulate that provide 8°F protection rather than lightweight covers offering only 3-4°F.
Consider your typical frost dates and wind exposure. Greenhouse structures in windy areas require reinforced covers like Planket Protector to withstand 40+ mph gusts without tearing.
Crop-Specific Requirements
Different crops demand different protection levels throughout their growing cycles. Cool-season vegetables like spinach and lettuce thrive under lighter covers like Agribon AG-19 that maintain airflow while preventing frost damage.
Root crops and hardy herbs benefit from heavier thermal protection during winter months. Brussels sprouts and kale actually improve in flavor when grown under insulating covers that protect from harsh temperature swings.
Size and Coverage Calculations
Measure your greenhouse beds before purchasing to avoid waste and ensure complete coverage. Standard row covers come in 6-foot and 10-foot widths, with lengths up to 100 feet for larger operations.
Calculate 20% extra material for proper securing and overlap at bed edges. Your investment ranges from $0.22 per square foot for budget options to $0.85 for premium covers that last 5-7 seasons.
Installation Best Practices for Maximum Effectiveness
Smart installation determines whether your row covers deliver promised temperature gains or become frustrating maintenance headaches.
Proper Anchoring Techniques
Secure covers using clips every 18 inches along greenhouse bed edges to prevent wind damage. I’ve learned that sandbags work better than rocks for weighting down corners – they won’t puncture fabric during strong gusts. Always leave 3-4 inches of slack between anchor points so covers can expand with temperature changes without tearing.
Ventilation Management
Open covers when temperatures exceed 75°F to prevent overheating that stunts plant growth. Install simple thermometers inside your covered sections to monitor conditions accurately. You’ll need to lift or partially remove covers during warm afternoon periods, then replace them before evening temperatures drop – it’s extra work that pays dividends.
Removal Timing Guidelines
Remove covers permanently when nighttime temperatures stay above 50°F for seven consecutive days. This timing prevents heat stress while maintaining protection during unexpected cold snaps. I’ve made the mistake of removing covers too early after a few warm days, only to scramble replacing them when late frosts threatened tender growth.
Conclusion
Investing in the right greenhouse row cover transforms your growing potential and delivers measurable returns through extended harvests and healthier crops. Whether you choose the lightweight Agribon AG-19 for frequent access or the heavy-duty Planket Protector for maximum durability you’ll gain weeks of additional growing time.
Your choice ultimately depends on your specific climate challenges crop requirements and budget considerations. Budget-conscious growers can achieve excellent results with Frost Protek while those facing harsh conditions benefit from N-Sulate’s superior thermal performance.
Remember that proper installation and maintenance maximize your investment’s value. With the right row cover and techniques you’ll enjoy fresh homegrown produce well beyond traditional growing seasons while protecting your plants from unpredictable weather events.
Frequently Asked Questions
What are greenhouse row covers and how do they work?
Greenhouse row covers are protective fabric layers that create microclimates within your greenhouse. They work by trapping warm air and providing an additional 4-10°F of temperature protection. These spun-bonded polypropylene or multi-layer fabrics allow light and air circulation while blocking wind, frost, and pests, extending your growing season by 6-12 weeks.
How much temperature protection do row covers provide?
Row covers typically provide 3-10°F of frost protection depending on the type. Lightweight options like Agribon AG-19 offer 4-6°F protection, while heavy-duty covers like DeWitt N-Sulate provide up to 8°F. This temperature boost helps protect plants during unexpected cold snaps and extends harvest windows significantly.
Which crops benefit most from row covers?
Cool-season crops like lettuce, spinach, kale, and Brussels sprouts benefit most from row covers. Root vegetables such as carrots and radishes also thrive under protection. Hardy herbs can continue growing through winter months with proper coverage, allowing for year-round harvests of fresh produce.
How long do greenhouse row covers last?
Row cover lifespan varies by quality and construction. Budget options like Frost Protek last 2-3 seasons, while mid-range covers like Agribon AG-19 provide 3-4 seasons of use. Premium heavy-duty covers such as Planket Protector can last 5-7 seasons with proper care and storage.
What’s the cost difference between row cover options?
Row covers range from $0.22 to $0.85 per square foot. Budget options like Frost Protek cost $0.22, mid-range Agribon AG-19 is around $0.45, while premium Planket Protector costs $0.85. Higher initial investments typically provide better durability and longer-term savings through reduced crop losses.
How do I properly install row covers in my greenhouse?
Secure row covers using clips every 18 inches along edges and sandbags at corners. Use hoops or wire frames to maintain airflow and prevent fabric contact with plants. Monitor temperatures with thermometers and open covers when temperatures exceed 75°F to prevent overheating.
When should I remove row covers?
Remove row covers when nighttime temperatures consistently stay above 50°F for seven consecutive days. This timing prevents heat stress while maintaining protection against late frosts. For pest protection, covers can remain longer but require regular monitoring for adequate ventilation.
Do row covers block beneficial insects?
Quality row covers block approximately 85% of harmful insects while still allowing beneficial pollinators to access plants when properly managed. The breathable fabric design permits necessary air circulation and selective access for beneficial insects during optimal growing conditions.
Can row covers be used year-round?
Yes, row covers can enable year-round greenhouse production when properly managed. They provide essential protection during winter months while extending fall and spring growing seasons. Proper ventilation management and seasonal adjustments ensure optimal growing conditions throughout the year.
How much extra material should I buy for my greenhouse?
Calculate your greenhouse bed measurements and add an extra 20% material for proper securing and overlap. This additional fabric ensures adequate coverage for anchoring points and allows for adjustments during installation without leaving gaps that could compromise protection.
