Choosing the Best Covering for Your Greenhouse

Spring is here and the changes of the season are upon us; the days are longer, the sun is warmer and we are gearing up for a new growing season. Growing vegetables in Upstate New York, which for us means Zone 4, presents some challenges, but with a little research, time and effort, those challenges are nothing compared to the benefits you will reap.

The season tends to be on the short side with our frostless nights falling mostly between Memorial and Labor days. So, how does a gardener grow all those great vegetables that take 90+ days to develop while maintaining a budget? Well, we’ve found our savior in a greenhouse. Growing or starting seeds in the greenhouse can add several weeks to both sides of the season greatly increasing the vegetable variety and yields for any grower.

Greenhouse Covering Upgrade

Our Greenhouse with its fourth birthday upgrades

We’ve been using our current greenhouse for three years. For its fourth birthday, we decided to give it an upgrade. We’ve used the same greenhouse film for the last couple years and wanted to find a new greenhouse covering that would protect our precious seedlings from the still cold nights until they are ready to be transplanted in the fields. But with so many options for greenhouse covering, how does one choose which to use? Is it better to spend more, or would an economical option work just fine too?

There are a few typical options for covering a greenhouse. Glass, fiberglass, polycarbonate or polyethylene greenhouse film are the most common. Each has its benefits. Glass is beautiful and traditional, but does not diffuse light, which can lead to overheating in the greenhouse. Polycarbonate and fiberglass both are excellent for light transmission, durability and strength, but tend to be more expensive. Polyethylene film is the most commonly used greenhouse covering in North America and is a highly economical, easy to install option, but is not as permanent as the other three.

Taking into consideration these facts, and our needs, we decided to use a combination of glass and polyethylene film. The glass adds elegance, durability and some weight to the lower half of our greenhouse. For the hoop section, we chose Thermal AC Greenhouse Film from Greenhouse Megastore. It’s an economical, all in one greenhouse film with great light transmission, anticondensate and drip control and at 6 mil, it has an R value of about 1.4 when used in a double layer with inflation. If you use a single layer of 6 mil, your R value falls to about .8 or roughly half what you would get with the inflated double layer. The Thermal AC film also has a 3 – 5 year life expectancy, which makes it a great choice for longevity as well.

For inflation, we selected an Inflation Fan that is reasonably priced and a good fit for our greenhouse size. With the inflated double layer plastic, a greenhouse grower could see upwards of a 40% reduction in their energy costs as the heat stays inside where it belongs and keeps their plants happy. Installing the fan is quick and brings so many benefits.

Now, all we need to do is install the new greenhouse plastic and fan and enjoy the jump start to the season that the greenhouse provides!


  1. Great idea using glass and plastic. Good way to use up old shower doors etc. CREATIVE SOLUTION.
    Megastore was helpful when I was researching fans and heaters. I got some good answers and directions for my questions. Thanks.

    Comment by margaret terwilliger — March 27, 2012 @ 12:30 pm

  2. yolanda_breidenbaugh

    Very nice! We have a hoop house, and just use the 6 mil plastic from the megastore ~ no electricity possible out there. It is great having fresh things to eat all winter and a place to start seedlings in the Spring. I love how you’ve combined the glass with the plastic.

    Comment by yolanda_breidenbaugh — April 15, 2012 @ 6:18 am

RSS feed for comments on this post. TrackBack URL

Leave a comment