The first time I had to dig a garden bed, it took awhile. That is to say, it took me about half an hour to do 10% of it, and then John took over because I was beat. And that was in a relatively bare patch of the yard, in April when the grass isn't growing much yet.
The next time, I did it in the middle of July in a thickly-sodded part of the yard. It. Was. Awful. We have this really matted kind of grass with runners connecting it all together, so you have to sort of chop at it to get through it at all. And then you've got all this sod that you don't know what to do with: either you chop it up and bury it (in which case that nasty invasive grass comes right up a week later), or you remove it and find that your garden bed is two inches lower than the rest of the yard.
I got maybe six square feet done a day, and that was working hard. I spent maybe a week on it, got enough for the beans, and gave up.
Awhile later I had the idea that I might have an easier time if I tried to kill the grass first. So I prepared the next patch by spreading newspapers over the grass, weighing the newspapers down with bark mulch, and waiting. The hot sun on the smothered grass did the job really quickly. (It did the same underneath the kiddie pool, sigh.) Two weeks later, the grass was still there, but it was yellowed and beginning to rot. I started to hack through it, and it was WAY easier. The stems, roots, and runners had all softened and were easy to cut with the side of my shovel. I did toss the dead grass, but much less soil clung to it than to the live grass in the other bed.
I prepped the next patch, and then got too pregnant to do any more. So I let the sun beat on that patch all through September and October, let it get rained on all through November, and let it get frozen in December. Today, it was another of those delightful unseasonably warm winter days (you know, the kind that drives you crazy because you feel like you need to plant tomatoes even though there is nothing alive in the whole yard) and I just had to dig that bed. (My motivation consisted of one part second-trimester energy burst, one part frustrated gardening urge, and one part conviction that there is no way I'm going to want to do this in March or April.)
Turns out "dig" was too strong a word, though. I cleared away the various sticks and leaves I'd used to mulch it, dug up a few clumps of onion grass that had poked through -- and I was done! The sod mat had completely decayed. Not only that, but the soil beneath was much softer than usual and the worm action was amazing. I usually don't find many earthworms in my yard, but this time there was at least one in every shovelful. Afraid to chop up all my lovely worms, I just raked through the top layer and covered it back over with mulch!
Next time I want to build a new bed, I'll remember to start in the fall. The effort is greatly reduced, and the result is much better -- with less soil compaction, too, I'm sure. I've also covered the grass in my last two beds in the past month, and we'll see how they do. The process seems to be working much more slowly on the dormant winter grass than it did in the summer, but hopefully it will make the last bit of digging at least a little easier. (Though let's be honest: I will not be digging those beds. They're for tomatoes and pumpkins, which go in right around the baby's due date. Either my husband, my siblings, or my in-laws are probably going to have to do the honors.)
Here's my technique, honed on several different beds:
1. Start, if possible, in late summer or fall -- but even a week or two before planting can still have good effects. Pick a day that isn't windy, with rain forecast for the next day if you can. If there's wind before your covering gets a chance to get wet, it may all blow away. It may even do this several days in a row before you get smart, if you're me.
2. Spread newspaper, if you have it, thickly over the bed. I use about three thicknesses, and I'm careful to overlap. If there is the slightest gap, the grass will grow through it. It likes to do this at the edges of the bed, too. (You can skip this step if you don't have newspaper. We just happened to have The Washington Post delivered to us in error all summer long. It helps block out weeds.)
3. Over the top of the newspaper, put some kind of mulch. Grass clippings and dead leaves are both excellent. Put as much as you have. Raid the neighbors' leaf piles if you have to, or the edges of the street where the drains are getting clogged with leaves. (This is why fall is ideal. I only wish I had gathered more leaves.)
4. Newspaper and leaves both tend to blow away at the slightest breath of wind. Add something heavy to keep it all down. Wood chips or sticks are good. If you used grass clippings, and plenty of them, those shouldn't budge. I've been using fallen tree branches, the twiggy part that's no good for firewood. You can just throw the branches back in the brush pile when you go to dig the bed, since they won't decay in just one winter.
5. If you're not expecting rain, water the whole bed thoroughly so it doesn't blow away.
In the spring, clear away the mulch and see how much digging -- if any -- there is left for you to do! The newspapers may even be completely broken down. Whatever mulch is left can be dug in or used to cover the bare ground between your rows.
Besides the new beds, I covered all of my already-broken beds from last summer with leaves and garden scraps as well. Erosion is a real problem here, plus I wanted to keep the onion grass and other winter weeds down. The soil beneath seems to be retaining its good tilth and getting some good worm action as well.
Is anyone else getting any garden work done at this time of year? That gardening bug just pays no heed to the calendar!