I am so not an expert, but when I planted nasturtiums and marigolds, they got huge and took up more space than I expected. I had two marigolds in one square and they were BIG. Also that looks like a lot of lettuce and spinach to me, you might want to plant less to begin with and then have a succession crop.

Love your diagram with pics and everything!!

Cool design. Nice work! You will have tons of lettuce and spinach so I suggest succession planting them. You won't have many beans that way and it seems you all like them. Other than that, it's a fair amount of work to trellis zukes and squash I hear, but doable.

Good luck and enjoy your garden!

Here is a link that might be useful: Sinfonian's garden adventure

Love your design plan - it looks great!
If you have room in the cinderblock holes you could probably plant flowers and herb crops in those and save the bigger spots for veggies. That way you could surround your veggies with protective type plants that keep certain bugs away and with plants that help bring in beneficial bugs and still have plenty of room for your veggie stuff.

One thing I did notice when I began setting up with cinderblocks is that the extra 8" on each side is definitely something to consider since it will make your beds much wider if you are going to have 4x4 inside area. That would make a 32" reach to the middle. If you are going to have a 4x4 total outside area then you would need to readjust for having less squares inside. I ended up just using wood because I didn't have the space for those extra 8" and didn't want to give up my inside 4x4. :)

Hmmm...OK too much lettuce. How about:

1: cantaloupe - cantaloupe - tomato - tomato
2: bush bean - bush bean - eggplant - eggplant
3: bush bean - bush bean - lettuce - lettuce (various types)
4: dwarf marigold - carrot - carrot - nasturtium

I had also thought about having brussels sprouts in row 2 (then I could play around with the bush bean and lettuce amounts ) but I think it's just too hot here to grow them.

Thanks for the warning crystabel. I was a little considered about the extra space cinder blocks would take up but hadn't even thought about the fact that it might be difficult to reach the plants. I'll look into it.

very good idea to plant beneficial plants!! that's the smartest idea i've heard from anyone!! (no offense!! LOL) especially looking at my squash/blister bugs i see out there now!! they are soooo bad sometimes!! and they love my tomato's. but if you plant basil with your tomato's and marigold with your tomato's you won't have that, i did that out back and i don't have that problem, i forgot to upfront, guess who is my regular visitor???? **very pathetic sigh LOL** but i'm slowly getting back on track again!! LOL
http://www.humeseeds.com/comp1.htm
http://en.wikipedia.org/wiki/List_of_companion_plants
http://www.gardenguides.com/how-to/tipstechniques/vegetables/vcomp.asp
here are some of the companion plant guides i use, or look at, LOL hope that they help you. ummmm.....i didn't use them in the front garden and as you notice, i have the problem, my back garden is a mess as far as the grass is concerned, but as far as the bugs, only dragonflies, and ladybugs. so ya, id' say it works!! LOL i planted LOTS of marigold and nicotiana and snapdragon though. LOL ~Medo
ohhhhh and by the way, your plan looks awesome!! i agree with the succession as far as the lettuce, but the spinach, man i'd just freeze what ya didn't eat, that stuff is awesome!! :')) ~Medo

On block 2, the squash may get a bit big if you plant bush squash... wait let me rephrase that, plant vining squash and make sure they are, otherwise you will not find the rest of your bed under them. I've 5 ft across per squash plant in the back now. (squash have been exiled to thier own row outside of the bed for thier bulling ways.

About that lettuce, how are you planning on picking it? If your plan is to grow them to full heads, it's too much, but if you're planning on picking leaves as baby lettuces that's about right (picking 1-2 outer leaves per plant every few days).

Those squash will be trellised. I'm following the spacing in the SFG book but if they grow too big I guess I can just have 1 plant in the back row.

I don't know too much about lettuce and haven't really thought about specific varieties but I want the loose-leaf type, or to just pick leaves as needed.

Nice plan.
I just wanted to make sure that you are aware of how fast those radish are going to come and go and let you know that you can plan to use those squares for other things after one round of radish or if you can just keep re-planting them after pulling them.
On the beans I learned my lesson this year I will plant more squares. I planted 2 squares of yellow wax bush beans and 2 squares of pole beans and have not had enough to really do anything with except snack on myself here and there. The bush beans for me did not get two pickings maybe they will for your zone. ***fingers crossed*** When I planted mine I had big dreams of using them for dinner for my little family of 2 1/2 and really only get to munch them here and there by myself while I pick the squash.
I was able to trellis my zucchini plant in one square. I used the white nylon netting and planted it really close to the trellis it wasn't really to time consuming just minor coaxing. The yellow squash probably will not trellis well or I should say mine did not they are more stout and bushy but if you trellis that one zucchini plant it will leave room for the yellow.
At least that is how it worked out for me.

If it were me you should take out half of your lettuce and plant more beans. You will need more than two squares for it to be worth anything. Learned that lesson the hard way.
Your squash row should be split in two squares, one yellow and one zucchini, trust me you will still be over run with both fruits and plants. That is a lot of carrots and radishes at one time, you could succession plant those squares and make your harvest more usable. Unless you want two eggplant a day I think that one plant is enough, but that is just me, they seem to really produce when they get going. I also thought that spinach was only 4 per square you have them set up for nine per, I could be wrong though.

Lettuce and beans were 2 things that I didn't have enough of this year. I eat salads almost every day. I had hmmmm 20 leaf plants and it just wasn't enough. BUT it also got hot and that was the end of them. Holy bitter!

I currently have 40+ leaf lettuce plants growing out there for fall and am so excited to have some extra to share with friends, family, and neighbors!

Now for beans. I had 27 plants. And that gave me a bowl full every couple days for a few weeks. Now they are all gone and I have platned more. This time 5 squares worth! (45).

Strawberries, strawberries, strawberries. My lil bitty strawberry plants have taken over. And while I just moved them to a 1x10 bed, I might just move them into the middle of that bed which is 2x10 and separated by high wood to keep them contained. They really do shoot off runners and go crazy!

Just planted my first SFG today with a fall collection.

We ended up with too much lettuce this summer from our traditional garden at least in terms of too much all at once. That is the beauty of SFGing. For our fall garden we planted a variety of greens in our first row romaine/bib, red sail/arugula, mesclun/mesclun, kale/kale. The last square has two types of kale, so each square has two types of greens except for the mesclun square. The second row is empty, we plan on planting a row to match the first row 3 weeks later so the harvest is spread out over some time instead of having way too much lettuce all at once.