I have a great north-facing porch (with east and west exposure) in a fourth-floor walkup. I have been worm composting for years, with a few flower boxes, and mostly giving away the worm castings.

Now I have acquired ten wonderful planter boxes, 1x1x2.5, which I would like to use to start a vegetable garden in the sky. I planted three of the boxes last summer, using an improvised and heavy soil mix. I got great greens and lettuce; the tomatoes and peppers grew green but didn't fruit, so I'll be focusing on greens mostly.

Now I'd like to fill the rest of the boxes and get serious. I have a couple of months to get ready. I don't have a lot of money, and don't want to lug stuff upstairs. I read that you can use shredded newspaper instead of sphagnum in a planting mix. See "Potting Mixes for Certified Organic Production" by the National Sustainable Agriculture Information Service at http://attra.ncat.org/new_pubs/attra-pub/potmix.html?id=California, where it says:

"Ground-up newspapers can be used as a substitute for peat moss in growing media. Newsprint should not be more than 25% by volume of the mix. Avoid the inclusion of glossy paper or paper with colored inks, as these are prohibited."

For me, the advantage of the newspaper is that I already have it up here, it's light in weight so it won't make the porch collapse, and I won't have to lug my papers downstairs for recycling, or buy other materials and carry them all the way up.

I'm thinking of layering the materials in the boxes now, and letting them meld a bit over the winter. A possible recipe would be:

1 part newspaper (shredded, moistened)

1 part perlite (do I need this? It's lightweight, but would something like fir bark be better?)

1 part worm castings

1 part garden soil (from the boxes I planted last summer)

Plus, some eggshells near the bottom of each planter.

Comments very welcome. Also suggestions about how exactly to grind up the newspapers. I've been tearing them into one inch strips for the worms, but that seems a little tangly for the boxes.

And, what should I plant that will make edibles in the somewhat shady exposure? Most of the balcony gets a few hours of sun in the morning or evening. It isn't ideal, but it's what I've got. Broccoli? Peas?

(This is for the 10a zone balcony. I'm also thinking about agroforestry and a small garden at my father's place in the 3a zone north woods, but that's a different topic altogether.)