6 Best Greenhouse Plastic Clips For Secure Covering That Prevent Wind Damage
Secure your greenhouse covering against wind. Our review of the 6 best plastic clips details their grip and durability for ultimate plant protection.
There’s no worse feeling than hearing that telltale flapping sound during a windstorm, knowing your greenhouse plastic is tearing itself to shreds. A well-built frame is only half the battle; the real test comes down to how you fasten the covering. The right clips are the difference between a secure, season-long structure and a tangled mess of plastic after the first big gust.
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Choosing Clips to Protect Your Greenhouse Film
The job of a greenhouse clip is simple: hold the plastic film tight against the frame. A taut cover sheds wind and rain effectively, while a loose one acts like a sail, catching every breeze and stressing both the film and the clips until something gives. This constant flapping is what causes microscopic tears that eventually grow into catastrophic failures.
There are two main approaches to securing film. The most common for hobbyists are individual snap clamps, which are C-shaped pieces of plastic that snap over the film and onto the greenhouse tubing. The other is a wiggle wire and channel lock system, which provides continuous pressure along the entire length of the frame.
When selecting snap clamps, material is key. Look for clips made from UV-stabilized, high-quality plastic. Cheap, brittle plastic will degrade in the sun, crack in the cold, and fail when you need it most. While they cost a bit more, durable clips are an investment that pays for itself by protecting your much more expensive greenhouse film.
The final, and most critical, consideration is size. A clip is designed to grip a very specific diameter of pipe. Using the wrong size is like using the wrong size wrench on a bolt—it simply won’t work. It will either be too loose to hold or so tight it breaks or damages the film.
Bootstrap Farmer Snap Clamps for Durability
When you need a clamp that will not let go, Bootstrap Farmer is a name that comes to mind. Their snap clamps are noticeably thick and rigid, designed for serious holding power. You can feel the quality in your hand; they aren’t flimsy.
These clamps are built for the long haul. Made from heavy-duty, UV-resistant plastic, they are meant to be installed and left in place for the season, or even multiple seasons. Their tight grip means they can be a bit of a workout to install and remove, especially in cold weather when the plastic is less pliable. This isn’t a flaw, but a feature—that stubbornness is what keeps your plastic secure in a howling wind.
Bootstrap Farmer clamps are ideal for the main body of a greenhouse, especially along the baseboards and hoops where you need maximum security. They might be overkill for a door or a vent you open frequently, but for a semi-permanent installation in a windy area, their brute strength provides excellent peace of mind.
Growers Solution Clamps: Easy Snap-On Design
Growers Solution offers clamps that hit a sweet spot between security and usability. Their design often features slightly beveled or rounded edges, which makes a surprisingly big difference. This small detail allows the clamp to slide over the plastic and onto the pipe with less force and a lower risk of snagging or tearing the film.
This ease of use makes them a fantastic choice for applications where you’ll be removing the cover periodically. Think roll-up sides for ventilation, temporary cold frames, or low tunnels you move from bed to bed. You can pop them on and off without a huge struggle or worrying about damaging your expensive film every time.
The tradeoff for this convenience is slightly less holding power than their heavy-duty counterparts. In most conditions, they are more than adequate and provide a secure grip. However, for a greenhouse on an exposed, wind-swept hill, you might want a more aggressive clamp for the most critical anchor points.
Wiggle Wire Channel Lock for Ultimate Security
For the absolute best protection against wind, nothing beats a wiggle wire and channel lock system. This isn’t just a clip; it’s a complete fastening system. You attach an aluminum or steel channel to your greenhouse frame, lay the plastic over it, and then press a coated steel wire into the channel in a "wiggling" motion.
The magic of this system is the continuous, even pressure it applies along the entire length of the channel. Individual clips create pressure points, but wiggle wire distributes the load, making it virtually impossible for wind to get a foothold and start flapping the plastic. It’s the standard for commercial growers for a reason—it works flawlessly. You can even layer multiple pieces of film (like a primary cover and a shade cloth) in the same channel.
The downside is cost and installation time. You have to buy both the channel and the wire, and screwing the channel to every bow and baseboard is a significant upfront task. It’s the premium option for a permanent, long-term greenhouse where you want to eliminate film replacement as an annual chore. For a small, temporary hoop house, it’s likely more than you need.
Johnny’s Selected Seeds Clamps: A Trusted Pick
Johnny’s has built a reputation on reliable, well-vetted products, and their greenhouse clamps are no exception. They don’t manufacture them, but they source high-quality clamps that meet their standards. When you buy from them, you’re getting a product that has been chosen to perform for serious growers.
Their clamps represent a fantastic middle ground. They are robust and UV-stabilized, offering excellent grip without being impossible to install. They strike a great balance, making them suitable for almost any application on a hobby farm, from securing the main cover to fastening shade cloth or insect netting.
Choosing Johnny’s is often about peace of mind. You know you’re getting a quality product from a company that stands behind what they sell. For someone who wants a reliable, no-fuss solution without getting lost in endless online options, their clamps are a consistently solid choice.
Farmtek Snap Clamps: Versatility in Sizing
Farmtek is a massive supplier for agricultural goods, and their biggest advantage is an enormous selection. When it comes to greenhouse clips, their key strength is offering a huge variety of sizes. This is more important than it sounds.
Whether you’re building a hoop house from 1/2" EMT, 3/4" PVC, or 1-3/8" chain-link fence top rail, Farmtek likely has a snap clamp specifically designed for that exact outside diameter. This versatility is a lifesaver, especially if you’re using unconventional materials for your frame. They take the guesswork out of finding a perfect fit.
This focus on precise sizing solves one of the most common points of failure in DIY greenhouses. By providing an exact match for your tubing, their clamps ensure you get the maximum possible grip. A secure fit prevents the plastic from slipping and is the first line of defense against wind damage.
Circle H Farm Clamps: A Reliable, Simple Choice
Sometimes, you just need a straightforward clamp that does the job without breaking the bank. Circle H Farm clamps fit that description perfectly. They are a workhorse product—simple, effective, and affordable, especially when you need to buy them in bulk.
These are typically no-frills, C-shaped clamps made from durable plastic that provide a solid grip. They may not have the refined, easy-on edges of some premium brands or the extreme rigidity of others, but they hold tight and last for several seasons if treated well. They are a testament to the fact that a good design doesn’t need to be complicated.
Circle H clamps are an excellent option for budget-conscious projects, low tunnels, or securing interior row covers. If you’re building your first hoop house and need a hundred clips, the cost savings can be significant. They prove that you can secure your greenhouse effectively without having to invest in the most expensive hardware on the market.
Matching Clip Size to Your Greenhouse Tubing
This is the most important rule, and it’s where most people go wrong: your clip size must match the outside diameter (OD) of your pipe. A clip that’s even 1/8th of an inch off is either too loose to be effective or too tight to install without breaking.
Don’t be fooled by the nominal pipe size. For example, 1-inch Schedule 40 PVC pipe has an outside diameter of 1.315 inches. In contrast, 1-inch EMT (electrical metallic tubing) has an outside diameter of 1.163 inches. A clip designed for one will absolutely not work on the other.
Before you order a single clip, get a pair of calipers or a precise ruler and measure the actual outside diameter of the tubing you are using for your frame. Write that number down. When you shop for clips, ignore the "1-inch" or "3/4-inch" marketing name and look for the specific OD measurement it’s designed to fit. Getting this right is the single most effective thing you can do to prevent wind damage.
Ultimately, the best greenhouse clip is the one that fits your pipe perfectly and suits your climate. Whether you choose the brute strength of a heavy-duty clamp or the ultimate security of wiggle wire, this small component plays a huge role in protecting your structure. A little extra thought and a small investment here will save you from the major headache and expense of a shredded greenhouse cover later.
