Greetings,
Dirtdigging, that is a very good question. That would have been my preference too, as one of my main objectives is minimal prep work. I may still do that. But I also want the project done and start planting with full capacity this spring. Here are the factors that are pulling me in that direction:
1) I'd like at least 12" total of good soil. I can either go up in height (building boxes) or keep it level (or semi-level, building mounds). which means I'd have to dig out the existing grass and some of the dirt below it, which is of questionable quality considering that the lot probably got bulldozed over when it was developed. I suspect only a thin layer of topsoil for the lawn, below it would likely be lots of small rocks.
2) Building and amending the soil over time is what I did at my previous garden. But it takes time, 5 years+. Now I want to bring in a couple truck loads of compost and get it done in one day. The boxes are to contain that material. Having sharp separations between the grow areas and walkways uses the small space more efficiently for growing. Mounds and un-delineated beds use up a transition area. If not contained, the light compost would run off in heavy rains.
Again, having said that, I may still reconsider, still time -thanks very much for suggesting this.
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And here's the latest progress, baby seedlings from the first batch. Exactly 1 week from seeding, the first ones emerged in 3-4 days, and stayed in the dark for 1 day before I started looking. I setup this quick and dirty incubator while I'm still working on the lighting setup.
incubator.jpg