Air Date: Week of April 24, 1998
Steve Curwood visits with Living on Earth's gardening expert Michael Weishan and they discuss everything you always wanted to know about dirt, but were afraid to ask. Mr. Weishan is also the editor of Traditional Gardening Magazine.
CURWOOD: Hey, Michael, what are you up to today?
WEISHAN: Ah -- digging in the garden to get the soil prepared for the first planting of the spring.
CURWOOD: Michael Weishan is Living on Earth's gardening expert as well as editor of Traditional Gardening. And we're out here in his yard, and he's going to tell us about the most important factor in gardening: good dirt. Michael, what makes soil good?
WEISHAN: Well, there are 3 essential factors to soil, and one is humus content, the amount of organic matter in the soil. One is the soil's fertility, its nutrient value. And the third is the soil's ability to drain, to shed water after a rain.
CURWOOD: All right, let's go down through your list. We've got humus content, drainage, and fertility. Well first, humus content. What do you mean by that, and how do we know where our soil stands?
WEISHAN: Humus content is the amount of organic matter, or humus, in the soil. And it's pretty easy to judge on a sort of a simple homeowner level. If you pick up the soil that's fairly dry and you crush it and it stays together like that, there is a decent amount of humus.
CURWOOD: Yes, nice and brown, too.
WEISHAN: Well the color's not necessarily important, that's a common myth. Soils can be all different colors and be equally fertile and good. But this just happens to be dark-looking soil to begin with.
CURWOOD: Okay. Now, you mentioned drainage. How do I know if it's draining okay? If I grab it and it stays together, that's fine.
WEISHAN: Well, you know, if it's draining okay, if whether after a rain the water soaks into the soil. If there's puddles on the soil surface you know you have a problem with a very clay soil, and the answer to that is to add sand or some other type of aggregate material.
CURWOOD: You've got some manure and compost for us here. The first question I've got for you, Michael, let's go over next to this thing --
WEISHAN: (Laughs) I guessed that. Actually, this does smell a little bit, because this is actually fairly fresh. And there's a caveat that people should know about, in that you really don't want to use fresh manure in areas where you're going to be harvesting food products. You want to have a well- composted manure, and by that we mean something that's been sitting out six months to a year outside and that has rotted. This is a little more scent- filled. This is chicken manure, and this is really potent stuff.
WEISHAN: Yeah, if people can get access to it, it's a wonderful manure. You don't want to breathe it in; there can be some problems with breathing it in. But it's a wonderful manure and exceedingly potent for the garden. You have to be careful not to burn it. And that's the other thing about the manures is that you want to add well-rotted manure, because when it first comes out fresh, it can burn the roots because of the urea in the manure. And when it's rotted that's not the case.
CURWOOD: Well, sometimes people use chemical fertilizers. It's a good thing to avoid, right?
WEISHAN: In general it's a good thing to avoid. I mean, as a quick fix it works sometimes, but you have to be very careful because the danger is that you will over-apply, not work it into the soil, and then it will run off into the water streams and promote algae growth and degradation of the aquatic environment.
CURWOOD: Okay, so now we're going to add some manure, right?
WEISHAN: Well not quite. What we're going to do is actually double-dig this soil first, because it's by far the best way to till the soil sufficiently and produce really good results in the garden.
WEISHAN: Steve, can you move that wheelbarrow?
CURWOOD: Okay, Mike.
WEISHAN: All right.
WEISHAN: Dig out a hole, and you take the contents of the first section and put it in a wheelbarrow, and then you move onto the next section, and you take the soil, the topsoil, and put it on the bottom of the hole, and then you add some manure or compost and you keep moving on down the line until you've got the very end, and then you take the soil you've put in the wheelbarrow and dump it at the very far end.
CURWOOD: So it's this great churning and switching, huh?
WEISHAN: It's a great churning and switching, and what happens is that you get much improved drainage and you've got the organic material down at the roots. And you also find in drier areas of the country that beds that have been dug like this need much less watering, because the roots can penetrate much more deeply down into the hidden groundwater, and that you don't have this issue of watering constantly, constantly, constantly through the summer.
CURWOOD: Double-digging. I should try this this year in my flower garden right outside the kitchen door, huh? It's not very big and it won't break my back, just take me most of the day.
WEISHAN: No, I don't think it will take you most of the day. It'll take you an hour or two to really do this well, maybe 3 or 4.
CURWOOD: This is New Hampshire, Michael, there's more rocks and soil.
WEISHAN: Well all the more reason, because you really then want to get some of the major rocks out and cultivate the soil. You know, you do the soil once and it's done right and it sits there. My grandfather used to tell the story about never doing anything half-assed, and this is exactly what you want to do. Why go through all the time and at great expense of planning a garden and only get mediocre results, when you can put a couple hours in at the beginning and really get great results from the same garden?
CURWOOD: Michael, thanks for talking with us.
WEISHAN: Oh, it's been my pleasure. It's a little harder work today; I didn't get as much free labor like I like to get. (Curwood laughs)
(Music up and under)
CURWOOD: Michael Weishan is editor of Traditional Gardening. And if you have a question for Michael you can reach him via our Web site. That address is www.livingonearth.org. That's www.livingonearth -- that's all one word -- .org. And when you get there, click on the picture of the watering can.
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