Might I recommend using something like this
https://www.amazon.com/ALEKO-Privacy-Backyard-Windscreen-Grommets/dp/B01LZ2MVAY/ref=sr_1_4?ie=UTF8&qid=1490390985&sr=8-4&keywords=fabric+fencing
as opposed to the plastic wrap?
I used to have a greenhouse in SoCal, built myself a hoop out of PVC and that worked just fine. The visqueen totally sucked though, couldn't keep temps below 90 to save my life because it seemed to absorb the sunlight (explains why it craps out on you eventually), trapped humidity inside, and caused way more problems than it was worth.
The windscreen I linked to you goes for about the same price, cheaper even at some places. Light penetrates through it much better than the visqueen, plus you get airflow from all the little holes in the screen. When I remade my greenhouse with the screen I noticed better results by the next day. I don't even think I had the visqueen up for a week before I tore it down and replaced it with the screening.