I know exactly what you're going through.
I was handing in one chapter at a time to my supervisor. One day he called me into his office to discuss the latest chapter, and he said, "you obviously weren't very good at english in high school."

, I wasn't the best, but i did finish in the top 10% of the class. At the time, I was told that my writing was so bad I needed to make an appointment with the science-writer-dude because my supervisor "can't look at my work anymore". Science-writer-dude looked at it and thought it was really good. The problem was, I don't write like my supervisor writes. That's it. I write simply, my supervisor likes to use latin (I say "by itself", he says "per se").
At the time, I started to loathe my supervisor and hate my thesis with a passion. I did learn something - I repeat myself a lot. In one chapter I discussed the same topic in 3 different paragraphs, right after each other. I thought they were all different. They did have different words in there. I come from the redundant school of redundancy. I was also told that I alternate between too much and too little detail. If I had my way, I would repeat and repeat and repeat.
Luckily, I had a chapter where every experiment went wrong - it was a hilarious tale of misfortune. I was told by my supervisor and thesis advisers that I don't need to include it... but it was the most fun to write. How many thesis include the sentence "the pups were subsequently cannibalized by their mother"? My pear shaped mice, that had gigantic fatty breasts, ate their pups, and attacked their mates...

Most of my insanity can be traced back to them. That was the only chapter where my supervisor didn't bang his head on the desk when reading it. Miraculously, it had the right amount of detail and no repetition. So, I rewrote most of my other chapters based on that. On a tangent, my final reviewers felt really sorry for me after reading that last chapter, and I think sympathy is underused when getting a PhD approved.
The moral of the story is, it isn't as bad as it feels. It is not an impossible task. Take one chapter, and break it down into it's most simple aspects. Then, begin writing as though you're talking to someone completely out of the field (like me), and then slowly begin to be more specific. It's a pyramid that's upside down. It's a tale, and you need to take the reader by the hand and lead them down the path.
My old lab didn't have the pressure to publish everything. It was more "the joy of investigating" rather than "publish publish publish". When we did publish, we ate cake. We were also quite poor. Now, I'm in a lab that publishes everything, and there is no cake. In hind sight, I prefer working without the pressure to publish. I used to be really confident with what I do, I felt like an expert in my field. Now, I was told that I'm an expert in my field and I don't feel like it. "Expert?

are you talking about someone behind me?"
So, if you'd like someone out of the plant field to read your review, email me. I can at least look for typos etc.