Tansparent Tarps instead of hoophouses.

Hoophouses are expensive enough that building moveable ones is a thing.
Tarps, stretched between trees and anchored to the ground, are popular choices for camping.
Could they be a lower cost version of a hoophouse?

I could be as simple as posts or trees at either end of a growing bed, a cable tensioned in between, plastic over top and pinned down on the sides.

Running a second line tensioned under the first could allow a second tarp, for a double layer of plastic or an outer layer of shade cloth.

There will be complications,  but it seems doable.

What would you do at the ends to hold in warm air? Just bunch it up and clip it together?

I know one of the tricks with putting up a hoophouse is getting the plastic tight, tight, tight so that it doesn't flap in the wind, which causes it to wear very quickly. That seems like it would be at least harder with so much less frame.

Working/cultivating at the edges, where there's not much room between the ground and the roof, might also be a problem. This might be minimized by using three ropes so the plastic has vertical walls, but that makes the design more complicated, which is getting away from the original idea.

Great points!
With no hoops comes fewer points of contact, which should reduce opportunitiesfor wear.
That said tauntness is as important for tarp shelters as it is for hoophouses.

I think we could achieve straits sides and make more of the tarp house usable, by mimicing the Philmont style dining fly , but that has its own complications.
Since we are replacing a relatively expensive and complex hoophouses, I think it's worthwhile to put in a few extra cables.


For closing the ends, I envisioned something like scissor doors.

I have put in wood walls and doors on both ends of my hoop house.  I scrounged most of the materials.. such as doors and windows. My hoop house runs approx NW to SE. So, having the northern end blocked by wood makes sense. I do have three windows on the north side to assist with venting. On the south side I have two windows and a small wood stove.. the stove location was dictated by prevailing winds during the colder months. The stove is intended to take the edge off of an early hard freeze.   I also keep  containers of water in it for mass. I do not use the hoop house in Jan, Feb, July, and August. I cover the thing with 10 mil plastic and reinforce the wear points.  I have learned to always be on the look out for suitable plastic.  Careful shopping significantly lowers the price.  At present I am in the middle of a rebuild.

I've had more experience than I would like with dealing with tarps.

Things I agree with:
1. The cheap white tarps can work quite nicely as a season extender. Hubby once let a whole bag of potatoes grow foot-long runners when I was called away to help a sick sister. I planted them in late August, covered them with a tarp held up by some bamboo garden hoops about 2 feet tall, and come Feb. I had a bumper crop of tubers.

2. The more a tarp flaps, the faster they start to get micro-leaks/plastic flaking off.

3. They don't like snow. Our snow is heavy, wet, and usually in the middle of the night when I'm not outside clearing it off...

4. I cut around the grommets in worn out tarps if the grommet isn't damaged, and I sew these onto new tarps so that there are a) more attachment points and b) attachment points where I want them.

5. I've scored a few frames from "car shelters" that have lost their tarps. The tarps used to be impossible to replace at any reasonable cost, but people got pissed about that and companies smartened up, so the frames may be harder to get now. However, most of those frames also don't cope with snow load the way they're designed. I took one 20 ft frame and cut the cross pieces in half, so I've now got a 10 ft shelter with much better support and it's coped adequately through several snow storms. We nearly lost a virtually identical shelter that didn't get the "shrinking treatment" and Hubby wasn't watching it carefully enough and we did loose an expensive shelter when he fell asleep and didn't put someone else on watch.  

6. I've put up plenty of camping tarps and most of them don't cope with more than light rain. Putting up tarps well is an art. I'm totally sold on the need for a good ridge line and will got one step further and suggest if you can tie up a solid ridge pole as shown in the Philmont design above, your odds of a good outcome in both wind and heavy rain will be higher.

A lot depends on what your goals are. I had an old piece of plastic hanging around. I've got a cucumber plant that has a lot of babies and I'd love to give it another few weeks of a little protection, but the weather is changing fast (we'd been mostly getting 14C at night and last night the low was 6.4C) I just used hockey tape to hold the plastic over top of the bed it's in as there was already a frame. It's not totally enclosed , but the goal is to "block the clear sky". I'll report back as to how it goes... we're expecting a big storm tonight with high winds... I'm not taking bets!

If you end up building a system William, please post pictures of the successes and the failures.  There are good lessons everywhere, many of which I wish I'd learned 15 years ago.

John, I can imagine two end walls  facing each other, with 5 cables strung in between, and plastic stretched over that.

Jay,I have had the same experience with carports, well a carport.
It got wrecked twice,  I repaired it once.
I was already thinking it could still be used, if the spans were shortened, sounds like it will work.
I think I will try this out along a garden wall, as season extension.

After scouting some potential locations, I think I know where I'll try this idea.
At my yarden I  have a 8 foot across stock tank that I am using for water storage.
It has a bunch of buckets in it, that are being sub irrigated.
Almost 20 feet away I have a box elder tree.