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pinkkpearls

Layering, Mounds, etc.

pinkkpearls
9 years ago

I am fairly new to gardening and wanted clarification on a few terms I have heard...

I am trying to do more of a mound type garden bed and I am unsure how I should go about doing it...

Should I just pour my compost, soils, etc. on top of the site where I want the bed then plant directly into it? Or do I build up the soil I have (mostly clay) and form that into a mound with my other amendments?

Comments (13)

  • jean001a
    9 years ago

    Take a look at this link ...

    Here is a link that might be useful: raised beds without formal sides - aka mound

  • gardengal48 (PNW Z8/9)
    9 years ago

    Ideally, it is best to disturb the native soil under the mound to some degree but not absolutely necessary. It depends a lot on the size of the mound and exactly what kind of drainage issues, if any, you may have.

    The terms 'mounds' and 'berms' are often used interchangeably but a berm is really just a large mound. Many folks mound up soil in planting beds to a much smaller scale than most berms. If this is your intention, you can just mound your good soil on top of what you have. If constructing a larger berm, checking for proper drainage may be more important.

    I am not a big fan of layering different materials to create either mounds or berms. Water percolation is always going to be better if the soil is uniform in consistency, so I'd advise mixing all your soil products together before forming the mound. The exception is large berms, which often have some sort of fill at their base but that tends to accelerate drainage rather than impede it.

    Sometimes it's all a matter of scale :-))

    Here is a link that might be useful: creating berms

  • toxcrusadr
    9 years ago

    Agreed, it's best to incorporate those amendments especially if it's not something like a vegetable bed that you can dig or till next season. Perennial beds and areas around trees and shrubs can't be dug up over and over so you should amend when you build them. Also, plants do better in a soil that's part mineral and part organic, in other words it's better not to grow in pure compost. If you're adding some soil and compost both, mix them and either till into the soil below or at least break up the surface before adding the new soil on top. I've made raised beds on heavy clay by bringing great soil I made in another bed and just placing it on top. It can work. With enough organic matter, eventually worms will 'till' the layers together, but it takes time.

  • pinkkpearls
    Original Author
    9 years ago

    Thank all of you for breaking down the terms for me...I had no idea what I was looking for, with your help now I feel much better. I have like 10-20 pounds of worm castings, vermiculite, peat moss, composted cow manure and a farm style compost by lady bug that apparently has a few different types of stuff in it. I wanted to work all that into my clay soil just not too deeply bc my house sits on a green belt.

    I have reinforced the fences a few feet down with some plywood in hopes I don't get anything digging under the fence. This bed will primarily have a lot of everything growing in it some bulbs, some annuals, mostly flowers, no veggies just yet.

    Think I need anything else in the soil?

    This bed will get morning sun (8am to 11am), afternoon shade for an a few hours, then the evening sun from about (4pm to sundown). Before I dig it, just want to be sure its a good location.

  • Kimmsr
    9 years ago

    You may be interested in Pat Lanza's Lasagna style planting beds.

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

  • gardengal48 (PNW Z8/9)
    9 years ago

    If the OP is planting mostly perennials and bulbs or even larger shrubs, building the bed via the lasagna method is perhaps not the best idea. As noted previously, a uniform soil consistency is preferred for any sort of permanent plantings, as ongoing cultivation is less with these types of plants, therefore eventual incorporation of all the layers is unlikely. Also, lasagna beds shrink in volume - it is their nature. The plants either settle so that adding new soil/amendments places them too deep or they wind up with their roots exposed, neither of which is desirable. This method works far better for seasonal crops, like veggies or annuals.

    Pink, depending on how much you intend to mound your bed, your materials may not go very far :) Is 10-20 lbs the total volume of ALL the materials or just the worm castings? How big is your proposed planting area? For example, if your proposed planting area was 10'x20' and you wanted to mound it 6", you would need 100 cubic feet of amendments - that's 50 of the standard 2 cf bags most prepared composts or planting soils come as.

    And as tox noted, you need some real mineral-based soil as part of the mix - at least 50%. Depending on how large your proposed new planting beds are, you may want to consider getting in some bulk planting mix from a local soil yard or landscape supply - bulk will always be significantly cheaper than bagged goods. And you can always mix in the goodies you have on hand.

    FWIW, I would omit the vermiculite for any inground planting. It's an expensive amendment that adds nothing. Once fully saturated with water, it collapses and any drainage benefits it once may have offered has vanished. It's not even a well-considered amendment for square foot gardening. It's nonorganic so provides no benefit for soil organisms or plant growth and can lead to excessively waterlogged soil. Which is what I assume you are trying get away from with your clay :-)

  • pinkkpearls
    Original Author
    9 years ago

    Gardengal48 forgive me, but can you clarify what real mineral-based soil is?

  • Kimmsr
    9 years ago

    Soils are composed of the mineral component, the sand, silt, and clay particles and the organic matter somewhere in the 92 to 95 percent mineral to 5 to 8 percent organic matter range.
    The mineral component comes from the rocks, stones, found in the area which determines the particle size. Sand is the largest of the mineral components with silt somewhat smaller and clay the smallest and most uniform.

  • gardengal48 (PNW Z8/9)
    9 years ago

    Mineral based soil is "real" soil - your native soil or topsoil.

    Soils are created naturally over time (a loooong time!) by the erosion of rocks. Sometimes these are local, sometimes they may be a good distance away and the small particles moved into a new location by glacial activity, rivers, flooding etc. Over tens of thousands of years, these small mineral particles mix with vegetation and animal matter and eventually, the result is soil, like you find in a garden or farmer's field or woodland. Soil that was originally rocks......mineral based soil.

    This is in contrast to organic matter - compost, manures, worm castings, bark, leaves, etc. There is no mineral based component to these materials and for plants to grow well, they need both. That's why it is important to blend organics with a mineral based soil if you are creating new planting areas or mounds/berms.

  • pinkkpearls
    Original Author
    9 years ago

    I've been tilling the amendments in with my clay soil..is that good enough, or do I need to go more?

  • gardengal48 (PNW Z8/9)
    9 years ago

    If it's producing the volume you need for the area, fine.

  • pinkkpearls
    Original Author
    9 years ago

    I dug up about 4 inches of my clay soil, then mixed it with about another 4 inches of amendments (compost, worm castings, old yard clippings) all together. The clay is no longer hard and there are no big chunks anymore like it was, when it first started. I went outside yesterday to look at the bed and picked up a ball of clay that crumbled away in my hand. I dug some of the soil back and the clay underneath has turned all dark and crumbly!

  • toxcrusadr
    9 years ago

    That's the ticket!

    Happy gardening.