One of the reasons to have a Lasagna bed is so you do not need to till, and there is no need to till your Lasagna bed. Spend a bit of time at this Lasagna Gardening web site to learn more about it.

Here is a link that might be useful: Lasagna Gardening 101

I am also very interested in lasagna gardening. I have (or have access to) cardboard, newspaper, rotting leaves, used coffee grounds, and manure in various stages of decompostion. Would these materials be adequate and if so how should I layer them. Thank you so much.

Okay, but that doesn't answer my question about how deep to plant my plants???

I am definitely not as experienced as the others but it is my understanding that ultimately, any organic material (OM) added will decompose. So theoretically, once the material you add on top is decomposed, the level will return to exactly what it was before you added anything (though this could take a few years).

My advice is to dig where you need to dig relatively large holes. Put some OM at the bottom of the holes and plant. This will cause them to be a little above the dirt level. Then spread your newspaper or cardboard around (as best you can) circling the plants you have planted. Then, hopefully, you've got some good OM to start with and put that on top.

Dried leaves is best for the very top, kind of looks better and also looks like regular mulch. Coffee grounds from Starbucks works as a start also but watch how much since if they are very thick, they can repel water.

Though some think of this as a science, I don't. Seems like when I am building a new garden and don't plan to till, I always make some decisions "on the fly" depending on how much OM I have and how muddy (or dry and hard) the holes for planting turn out to be, etc.

Plant your plants and seeds as deep as you would in "regular" soil.

I started one lasagna bed last fall and two this spring. I planted my seeds and transplants in the lasagna beds just like my plants and seeds in my "in ground" gardens.

In the two raised bed kits I constructed this spring, it is easy to see how much my lasagna beds have broken down. They were approximately 14" deep, and they are about half that now. Everything is growing happily, no tomatoes, beans, delphs, garlic, basil, melons, etc. are falling over or look stressed.

In the fall, after I have done some clean up, I will empty my compost bins, shredded leaves, more UCGs, and shredded paper and cardboard into the lasagna beds to start prepping them for next spring. I expect that all the perennials will push up through the compost/mulch/lasagna. Plants like delphs, prone to crown rot, I will take care with how I mulch/put them to bed for winter.

Just my 2-cents and lasagna planting/care plans. :)

cheers,
Norabelle

No experience here, so this is a total guess.

Either your plants will settle along with the matter in the bed, or you'll need to add more matter later.

I think the plants will slowly lower as the level lowers -- like something light floats in the top bit of water in a glass. Imagine the water draining out of the bottom of the glass -- that small thing (like an insect) usually goes lower and lower in the glass because it stays in the water. Just like your plants stay in the dirt/OM.

I don't think a plant inside a lasagna bed works like an island in the river, where the lower the river goes, the more island is visible. It's gotta be more like a floating dock -- to continue the analogy: as long as the bed doesn't get bone dry (i.e. it's been years and you haven't top dressed, etc), you should be ok.

Now, remember I said that I have zero experience other than reading on gardenweb.