Improving Soil Structure

Improving Soil Structure

Part of Ep. 602 Back to Basics

Learn how to condition your soil with organic matter.  UW-Extension Soil Scientist Sherry Combs demonstrates how to made soil rich and moist.

Premiere date: May 31, 1998

TRANSCRIPT+
Wisc Gardener Transcript: 

Shelley:
This is the kind of soil that every gardener dreams of-- rich, moist and crumbly. Unfortunately, most of us don't start out with something this nice looking. I'm with UW-Extension Soil Scientist, Sherry Combs. Sherry, you're going to show me how to turn what I've got in my yard into this beautiful stuff.

Sherry:
We'd like to, yeah.

Shelley:
We're talking a conditioning, rather than a soil fertility-- making it a better soil.

Sherry:
Yeah, most homeowners have high fertility levels, but they still don't get the crop production they would like. Mostly because they're limited by drainage or excessive water flow or perhaps compaction. So, those are the types of problems we need to work on.

Shelley:
What types of soils are you looking at for wisconsin?

Sherry:
Most homeowners claim they either have sand or clay. And that's not really the case, but we certainly have those extremes in Wisconsin. This is a sandy loam. And you can see that it doesn't hold together very well because of the sand content. Water will flow it rather excessively. So, water management is critical in this type of soil. This is more of a clay-type soil. You can see that right off. It tends to ribbon because of the clay. And when it's dry, it doesn't drain water very well at all. Aeration is limited and it can become very compacted like after construction.

Shelley:
A real problem. So, how do we get to this type of ideal, then, if we've got one of those two soils?

Sherry:
Well, we can get the quality moore like a silt loam from these two types of soils by adding organic materials.

Shelley:
Is this something I'm going to do just once and then I'm done?

Sherry:
Preferably, you'd do it each year and you'd do it a lot. Because, about 90% of what you add becomes co2 and water after the microbes use it for their food. So, you're only left with a small portion of it to make some of the changes happen.

Shelley:
So, it's gone. You really have to re-add it. There are a lot of choices for organic materials. Can we look at some of them?

Sherry:
Yeah, let's take a look.

Shelley:
These are just a few of the choices available to gardeners-- grass clippings and leaves. We all have access to this.

Sherry:
Just about! Another one for gardeners would be the residue from the previous season's crops, too.

Shelley:
The chopped up garden stuff.

Sherry:
Instead of putting it out on the curb for pick up, you might as well put it back in the soil where it can do some good.

Shelley:
Sure-- make our soil a little better.

Sherry:
These are some materials that some gardeners might have access to. Sawdust and shredded bark are good choices, but you have to remember to add some extra nitrogen. You will tie some up when these decompose.

Shelley:
So, they're worth using, but add a little extra fertilizer.

Sherry:
Yeah, to avoid a nitrogen deficiency. Peat moss is available, I think, at just about every lawn and garden center. It's a good choice. It may be a little pricey if you're doing a large bed. But it's certainly a good choice. I've got some composted manure here that I'll be working in later. Composting is nice, because it reduces the bulk from your fresh materials. So, you can actually get more material on with less bulk than if you use the fresh.

Shelley:
Now, we're not layering any of these organic materials on top of the soil, are we?

Sherry:
Well, in order to change the physical characteristics we talked about earlier, you have to incorporate it at least to the depth of tillage and maybe even a little deeper.

Shelley:
So, I'm out there digging. Okay, I need the exercise. Thanks, Sherry.

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