1) Not sure the best way to prepare the plot- till, double-dig , or a modified lasagna method? I say modified because I don't know if I could get enough raw organic matter to do lots of layers. If I had a couple layers of cardboard/newspaper, followed by chopped leaves and straw, could I just fill the rest of the box with a bulk compost/soil mix? Also, my soil test revealed a ph of 5 and they recommended mixing in lime. If we went with more of a lasagna method, don't know how to incorporate the lime- maybe sprinkle on the grass/soil before putting down newspaper/cardboard?

2) what is the best material to build the frames with? There seems to be a lot of debate whether pressure treated wood is ok or bad, which is confusing. I feel like there are better uses for cedar than in my garden, but don't want to have to replace rotted wood in a couple years (like pine). Any thoughts on Douglass Fir, which is available at our local HD? Or the composite decking like Trex?

3) keeping out critters. We have rabbits and squirrels but not sure about voles. That worries me. I've seen recommendations to staple hardware cloth to the bottom of the box, but will that interfere with root systems? Gotta think it would affect root crops if nothing else. Not sure if its worth the effort, but don't know how to deal with digging critters otherwise.

Thanks in advance for any input!!

You can use a rototiller, but, I think you'll find that youll be fighting a lot of weeds that way, particularly if they are a problem right now.

I don't have a problem with PT wood, but if you do, then the Trex decking would work great, though, it's not cheap. Other then that, I have even used fence slats for raised bed. They don't last very long, but they are very cheap.

I don't have problems with burrowing critters, just rabbits and squirrels so my garden is all open bottom. I, like you, believe that weed fabric and the like stapled to the bottom is an impediment to the roots. I am also fortunate that voles and moles do not live here. As for the above ground pests, I have a fence with a gate around my garden for rabbits, and it keeps them out fine. I have a bb gun for squirrels (not that it helps, it just makes me feel better).

2) there is no "best material" for building the beds. Rather there are umpteen choices available and they all work fine. The choice is yours depending on the appearance you want and the $$ you want to spend.

The anti-pressure treated wood crowd is woefully out of date since the dangerous chemical process was outlawed in 2002 and current processes are safe to use. I would certainly pick it over any untreated woods unless you want to spend the money for cedar or redwood which most don't. And the composite wood is also expensive. If money is no object then decorative stone is another option.

3) fencing is the only effective option for most critters. Whether or not the hardware cloth would interfere would all depend on how deep you make the beds.

it is currently lawn (well mostly weeds) and clay soil. This winter has been quite wet and the ground very soggy. The yard also slopes downward slightly towards the back, but certainly not steeply. For these reasons, raised beds seem to make sense.

IMO none of that means you need the added expense and work of making raised beds or their limitations. If you want them, fine. But if not then each of those factors can be easily resolved.

However, IF that spot is chronically soggy with poor drainage then it will be a problem even for raised beds so it would need to be fixed first.

Dave

I am real beginner veggie gardener.
I did as you mentioned in your original post, #2.
07/06/2013:
-since it was late in the season, I used anything to frame couple of beds (couple of 2x10, some blocks & bricks).
-then 3 layers of cardboard directly over the grass;
-than thicker layer of shredded+unshreded leaves (from fall 2012-some were shredded with lawnmower & stuffed into black garbage bags with few holes for ventilation)
-then as much soil as I could find (mix of little compost from my small composter+leftover of triple-mix bought in bulk+some bagged soil)
-then I planted tomato plants that were growing in pots until then, and few peppers.
Peppers didn't do very well, but tomatoes did - considering how late & what I planted them in, they did great.
After tomatoes I planted garlic late in fall, will see what I get this spring.

So I would call it 'modified lasagna in-a-hurry'.
It was spur of the moment decision & I didn't have any proper materials (& didn't have access to the property earlier anyway).
Photo below shows work in progress - you can see cardboard on the bottom.
There were practically no weeds in the beds. They were approx. 12" deep only (to cardboard -may not need any deeper, depends on what you want to grow).
No tilling, didn't remove any grass, didn't add any amendments otherwise.
So maybe lasagna (with you having more time & being better prepared) would still work? This was in zone 5a.

Rina

One more question- I'm a bit concerned about the sturdiness of the frame- we have two boards end to end on each side. They're connected together but worried that point will bow out once we fill with soil. I heard that there are metal stakes that you can put on the outside of the frame to help reinforce, but don't know exactly what kind of stakes I need and where I can buy them. Any recommendations?

If it's not too late, I would really recommend trying to incorporate some of the clay into your beds. Clay has a poor structure and is acidic, but it has lots of nutrients and good qualities that are often overlooked. You just need to mix it with soil amendments like compost, be patient, and watch it become awesome over the years. You have to take a long term view with it. (And I am saying this from experience. You could make pottery with what I have in my yard.)