Hi Richard,
Here's some feedback

Unfinished bits:
- Footer area should be filled out
- There is a bit of Lorem ipsum dolor going on at the top of the Stills page
Stylistic bits:
- some of your blocks shift in size depending on which page you are on (look at the news box on the home page and again on the contact page)
- I know you can make your header image so much better. Maybe render out a long strip of your latest vegetation test, I think it would look great.
- your shop image links have a default blue border around them after you click through them. You may want to set border=0 in the links to get rid of that.
- not a big fan of your fonts
- sidepanel button layout is perhaps a bit dated

All told for a work in progress it is pretty nice and easy to navigate. I like the fixed layout etc.
What I'd really like to know however is why you never posted the image with the pots against the wall with the blue window... It very well could be a photo and the overall composition is really fantastic.
Hopefully these suggestions help out and are not more critical than you were looking for.
-ryan