1 no you don't want use newspaper you want to use weed cloth.

2. you need to read book for the correct square foot soil mix

definitely, i had the same thing going, went weedblock, 2 layers, and not only does it keep the weeds/grass from poking, the mole has yet to get in to my garden...

shouldnt have to mess with soil under except to get it level. i didnt at least.

i didnt exactly mix soil per the book, but i was pretty close.

also, not sure where youre at specifically, but i dug mine down about 3-4 inches into the soil, and its helped with temperature, and the grass creeping in(we have bermuda, and that $$$$ gets into everything)

Learning moment - That's what's in my garden - Bermuda grass!!!

I haven't started work on my exact mix yet, but will probably do 1/3 topsoil, 1/3 compost and vermiculite/peatmoss... How deep will it need to be over the weedblock to support beans, squash, tomatoes, etc (I'm assuming if weeds can't com up through it, that vegetables can't grow down through it)?

Gunner - so you dug up the bermuda grass with the top 3-4 inches before putting down the weedblock? Did you use that soil in the garden, or discard it as possibly contaminated? What did you use around the perimeter - boards, cinderblocks, something else? I'm still undecided about what to use, but if the bermuda is going to creep under boards, then that may sway my decision.

grass was already gone mostly. the area was mostly bare after removing a crappy old shed. the year before we planted a garden in that are, but theres wasnt really grass. what grass/soil i did peel up, i placed elsewhere in the yard(i have a dog, and hate watering the lawn, so bermuda works for me)
i dug down a few inches(admittedly it was accidental as i was trying to get it level more than anything) put down weedblock fabric, two layers(one direction then the other perpendicular), then i built the box on top of it.

occasionally ill catch a bermuda runner trying to sneak in through the corner, but thats about it. I get more crap from the lawnmower blowing it in than bermuda creeping in/under.

the last one i built i used trex, 1x6 decking boards, 2 high, and thus far its worked for everything ive grown(tom, beans, potatoes, lettuce, carrots, broc, peppers, etc). some would say thats overkill for most plants, but its less i have to think about/plan for ultimately.
if you go trex, i dont recommend longer than 6ft(i built the neighbors 4wx6l and it could maybe use a little structure in the middle, not noticable unless you kneel on it, it bows in a little)

other things ive learned that would help also if you go that route, let me know i can probably email/post some pics if you want later

i dont have the room for cinderblocks, and it would look bad around my trellis/brick patio that surrounds the garden. also may want to consider the lime used in the cement block. Ive heard it can leach into soil and mess with PH a little. also if its getting alot of sun, the area near the block would be considerably warmer. not sure what youd be growing but its something to think about.

it would be cool to have vegetables growing inside and little marigolds or something growing in the holes...

Learning moment - That's what's in my garden - Bermuda grass!!!

I haven't started work on my exact mix yet, but will probably do 1/3 topsoil, 1/3 compost and vermiculite/peatmoss... How deep will it need to be over the weedblock to support beans, squash, tomatoes, etc (I'm assuming if weeds can't com up through it, that vegetables can't grow down through it)?

Gunner - so you dug up the bermuda grass with the top 3-4 inches before putting down the weedblock? Did you use that soil in the garden, or discard it as possibly contaminated? What did you use around the perimeter - boards, cinderblocks, something else? I'm still undecided about what to use, but if the bermuda is going to creep under boards, then that may sway my decision.

being that you asked again, haha, i didnt use any soil from my yard in the garden. over the past few years digging ive found some questionable things in the dirt, so i went with brand new soil. i used a lot of organic garden soil(i was ignorant at the time) and probably not enough vermiculite. i do add all my compost every year, and if i find vermiculite on clearance ill throw a small bag in. i treat the soil like its in the earth now vice a really big container.

reading some other posts around here, id also recommend some kind of mesh screen on the bottom to ENSURE rodents wont burrow in. ive never had them in mine with just weed block, but after reading, i kind of wish i had done that as the moles have got to be unruly around here(neighbor behind me does ABSOLUTELY nothing with his yard i think theyre coming from there. no, i know they are, as i can see their stupid little mounds coming under the fence)

Hi Gunner and sctn
Good work in using the trex for the bed frames.
I've been replacing my double stacked 2x6 rough sawn white cedar with grey Veranda brand decking from the Homedepot. The cedar beds only lasted 20years and house lots of bugs. The friendly store manager calls me when she runs a 10% sale and I buy enough to replace a row of beds if I can. I buy the 16 ft boards(cheapest) and cut them in half in the parking lot with a little cordless ryobi circular saw. Then they fit in my trailer. A run to the local steel supply gets me 2"x 20' lengths of angle iron that I cut into 10" lengths with a chop saw. 24 pieces makes enough for 4, 8'x4'x1' beds with a centerboard at 4' to keep them from bowing out so I now have in effect, 2 4'x4' beds in each frame. The six pieces form the corners and attach the top pieces to the bottom. I drill 8 holes in each, staggered so the 1/4 bolts don't interfere with each other. They get 3 coats of rustproof paint and time to dry in the hot greenhouse too. Doggone galvanized bolts, washers and nuts are expensive!
We don't have Bermuda grass here but the equally invasive quack grass. So every spring I spend a day or so digging along the edges of these beds pulling out the amazingly long runners this damn grass has. My record so far is 11.5' for a single runner that went under 3 beds. The weed cloth is an excellent idea but the raised portion of my bed is only the top half of each bed. Every couple of years I do a complete texturizing double dig of the top 12" and the bottom 12" below adding as much compost as possible. This also gives me the chance to sever the roots of a cottonwood tree that throws its roots there from a neighbors yard. It's a good workout for sure but now that I'm getting up there in years maybe it's time to start thinking of weed cloth : )
The last time it cost me approx $500 for 3 8'x4' beds but cedar has really gone up and I don't think I'll ever have to replace the veranda beds.
20 years ago Mel hadn't made his mix yet but I wanted good soil so I ignored the old farmers adage "Add sand to clay, throw your money away." and bought a truckload of sharp sand from a local gravel pit. The soil in my garden then was blue silty clay that got a glossy sheen when you stuck a shovel in it. I took 8" of the clay and sifted and mixed 12" of the sharp sand with it resulting in a heavy clay loam that I poured into my frames. Over the years, compost, cover crops and especially charcoal activated by a cycle in the compost bin have turned the blue clay a deep brown at the lowest part of my bed. The MSU ag extension office says the blue is iron in the poorly oxygenated soil. The brown color says it is now oxidizing.
If I were to do it all over again, I'd be sorely tempted to buy bags of the Miracle Grow Organic Garden Soil the local Big Lots sells in 2 cubic ft bags for $8 apiece, $6.40 a bag on sale and use it as a fourth ingredient in a Mels mix.
Sorry for the rant, just felt like typing.