Ever plant too early in the season and have a frost come in and threaten to destroy all the seed starting, transplanting and babying you've done to-date? Ever want to extend out that season for those fall cool-weather crops or late summer crops that can't handle the first frost of fall? Cold frames are good, but I'm even happier with the hoop covers for season extenders or plant savers. I know pictures and plans for these are all over the internet if you search like I did, but I wanted to share my experience with you. They are cheap, you can easily make them as tall as you want and they set-up and take-down in as little as 10 minutes, all by yourself.
Hoop covers probably the easiest and one of the cheapest insurance policies for your garden you can have. You can purchase the PVC pipe, brackets, plastic and clamps for around $25, and it's not double for two as you can buy bigger lengths of plastic for a little more money. All you need is cheap PVC pipe in 10 foot lengths for a standard 4 foot bed. I bought whatever size was on sale, along with one pipe that was big enough for the others to fit into. Then I bought rust-resistant C clamps for the larger pipe. Finally I grabbed 4-mil clear plastic tarps that come in 10x25 lengths or longer.
To construct your mini-greenhouse, take the larger single pipe and cut 6 inch sections out of it using either a pipe cutter or a hack saw. You need 2 per side of your raised bed. To install them, simply attach them vertically to the side of your bed with the clamps like this:
These short pipes will remain in place for ease of set-up. Then, when you want to set up your hoop house, just stick one end into the short pipe and bend it over to the other side. I find a 10 foot pipe fits perfectly over a 4 foot bed.
After two years of using these, I find storms can wreak havoc on your hoop houses. Sure it's easy to fix, but who wants to go out in a storm or the snow to do so. Adding a top support can add to the stability of the house. Just take a straight PVC pipe and attach it to the top with twisty ties. I drilled a hole in both the center of the arch and the top beam. Then I can run the twisty tie through the holes.
I actually left the hoops up all season last year and it didn't hurt a bit. It makes it very easy to set up cover. Just throw an appropriate length of 10 foot plastic tarp over the hoop and you're covered (make sure there's enough to cover the ends of the tunnel). I use 4-mil plastic because it is sturdy enough to last a few seasons of harsh weather and yet not too opaque like 6-mil. To connect the tarp to the bottom of the hoops, I started using jumbo binder clips, but they rust to fast. Then we found plastic A-clamps at the dollar store in packages of 6 or 8 for a buck, and they don't rust! See the pic below in the top right corner. Handy things to have around.
If by chance you don't use raised beds, you could drive stakes into the ground on the edge of your garden and put the pipes over the stakes, so don't think you need raised beds to use hoop covers.
Hoop covers can extend your growing season by a month on either side, act as a mini-green house for heat loving plants in summer, or even allow you to garden all winter long in some climates. I call that a cheap garden aid!
I like to think they're also garden multi-taskers. You could just as easily throw shad cloth over the bed during the summer to help cool-weather plants keep from bolting. And I'm actually planning on throwing bird netting over them next fall to let my chickens hang out for a day in each bed to clear the vegetation, till the soil and fertilize the bed for spring. I bet if you think about it, you could find more uses in your own garden. But when we got a freak snow storm last April, boy was I glad these set up in 15 minutes in the dark.
Enjoy your garden!