g'day jaimee,

it is all about using what is available, generally economically, you have lots of basic questions all of which can be dealt with using some common sense. as for garden edging it is whatever turns one on and what can be economically maybe the demolition yard might have something that is cheap.

our gardens have always incorporated the hugelkultur process before it became the catch cry of sustainable gardeners.

we use mushroom compost from the farm for our final layer in the gardens, this time around we will be using corrugated roofing as edging to raise the beds higher (old timers), we pushed down some trees on our property and have some of this material for the first layers in the gardens, we have top soil from creating the building site, this will next be used (generally though we never add soil in as we don't believe in bringing in soil from an unknown source.

we can still access mushy compost so will still be using that as final layer, and we are currently gathering slashed 1 meter high grasses from adjacent properties that have recently been slashed this will save us buying mulch for a bit.

there was some soil here pushed into a heap from doing the septic which contains composted grass we have added kitchen scraps to this dirt for our second last layer. already holding stuff in the freezer to be added into the beds as we go.

anyhow for now check our bale garden feature:

len

Here is a link that might be useful: lens straw bale garden

I'll do my best to answer your Qs:

Yes, smother existing vegetation with cardboard. Overlap the pieces & wet them down. Some people do remove the sod prior to hugelkultur, so they can save it to use in the upper layers of the beds to retain the top soil. It is a huge job to remove sod, so I understand your desire to skip. I am familiar with hugelkultur, but I've only buried wood in trenches and not layered up entirely. We have created many new garden beds by sheet mulching or lasagna gardening right on top of sod or weeds. Initially it is mounded quite high, but shrinks each season, so now some beds are just raised about 6" higher than the surrounding area though still higher in the middles as we built large berms for the beds to increase drainage.

Wooden sides are going to be expensive at the height to cover the old wood you're putting in. Once plants are growing the sides of the mounds will be less noticeable. Height depends on your wood unless you plant to split it to fit inside the sides. Shrubbery will be similar to wood chips taking a bit of nitrogen to decompose, but balanced with manures or other greens it works fine. I've done it only in trenches or chipped as mulch in paths to later be raked onto beds after composted at least a year. Remember the height will shrink in volume considerably as it decomposes, so with sides you'll need a plan for adding additional material.

Probably can't have too many leaves & the balance of greens to browns won't matter too much. If you start with brown & layer alternately & end with brown you're putting 2 browns for every green, which is the goal.

Yes, manure is very useful for soil fertility and to balance out the browns. Craigslist might be a good place to find it free. You could stop by a farm close to you that would be convenient. Most around here happily give it away free if you haul and some even deliver.

If you're already purchasing wood and making the sides your budget may be at max before you even get to the compost layer. If you're able to start a compost pile now you can then just spread that partially worked pile on top of the beds. Read previous posts about composting. If not, you can just add what compost ingredients you acquire by then.

If you have surplus dirt from elsewhere that might be useful because it won't shrink as much as the organic matter. I don't think it's necessary, but the volume of organic matter needs to be at least a foot deep over the wood so that by spring you have something to plant in for roots to secure your crops.

After the leaves fall it's too late to start any vegetables here, so might be the same for you in zone 5b. We plant garlic in October to harvest in mid summer of the next year or onions to harvest in spring as green onions. Everything else is planted in July, August & September to mature in fall for harvest over winter. Some of the later crops can be overwintered as seedlings to mature in early spring depending on protection provided and the severity of our winter weather.

Cover crops are usually turned over to decompose though we've planted right through self sown arugula and kale.

Mulch is useful to retain soil moisture, but usually only spread after soil warms in spring. When tulip petals fall is a good indicator of time to mulch.