Hi Roxy,

Yes, use cardboard, then add 3-4 inches of compost or bark dust. Compost is better. Make sure you water it until the rains start. You will probably have to weed it a bit this fall. Let the winter rains and the soil biota and worms decompose the cardboard down into a nice, rich soil for you. If you use plastic, you will bake the soil biota and kill them. This is the way you sterilize the soil if there is disease but you kill everything, including the grass and then you have to dig up the dead grass anyway. Make it easy on yourself and your garden. Use the cardboard.

You might want to find out if you can build raised beds too. YOu can put the cardboard under the beds, then fill with good soil designed for raising veggies, rather than having to deal with trying to make what you have work. Plus, raised beds just generally work better in our climate for vegetables. There are a number of reasons for this, which you can read in the section on veggies, but it also would make removing these later relatively simple, if labor intensive.

And yes, grass is easy to replace later.

Honestly, stone seems impractical to me for vegetable gardening, but I suppose that's might just be me. It would certainly make using a rototiller a challenge, though...

There are lots of options for raised beds though. The simplest is to simply mound up the soil in a berm, with no firm sides. I have seen this done several times in pea patches, even once done in an interesting spiral and s curve design that was pretty as well as functional. It was, if I remember correctly, planted with sinuous, intermingled lines of onions, lettuces, parsley and carrots. The darker leaved lettuces and the contrast in foliage between feathery carrots and spiky onions, etc was really quite beautiful.

You can of course get untreated lumber as well, or use plastic. I know the manufacturing of the plastic lumber still leaves a bit to be desired on the "green scale" but it works beautifully for raised beds. There are even handy kits available that have cool interlocking corner pieces, that aren't too expensive (google it if you are interested).

You can use cinder blocks too, though personally I htink they take up too much width, but you can make them high enough to be able to sit on them, which makes weeding chores much nicer. Course, if you are doing a lot of raised beds, this is heavy lifting to build, and though the individual bricks aren't that expensive, it adds up if money is a consideration.

You can also make your own slabs, and tilt them up to make a kick ass wall for the raised bed. 4x4s for corners to hold them up, and a 1x4 or 1x6 on the top to finish it and you have a really stylish raised bed, especially if you do leaf impressions or some kind of mosaic work on the concrete slabs showing. One of these days I will do this in my own garden *grin*.

There are probably other ways to do it too. Raised beds are one of those things that if you get creative, you can do in a number of different ways.